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http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#Elena
Elena
  iex(1)> true === :true true iex(2)> false === :false true iex(3)> true === 1 false  
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#Elixir
Elixir
  iex(1)> true === :true true iex(2)> false === :false true iex(3)> true === 1 false  
http://rosettacode.org/wiki/Caesar_cipher
Caesar cipher
Task Implement a Caesar cipher, both encoding and decoding. The key is an integer from 1 to 25. This cipher rotates (either towards left or right) the letters of the alphabet (A to Z). The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A). So key 2 encrypts "HI" to "JK", but key 20 encrypts "HI" to "BC". This simple "mono-alphabetic substitution cipher" provides almost no security, because an attacker who has the encoded message can either use frequency analysis to guess the key, or just try all 25 keys. Caesar cipher is identical to Vigenère cipher with a key of length 1. Also, Rot-13 is identical to Caesar cipher with key 13. Related tasks Rot-13 Substitution Cipher Vigenère Cipher/Cryptanalysis
#Ursala
Ursala
#import std #import nat   enc "n" = * -:~&@T ^p(rep"n" ~&zyC,~&)~~K30K31X letters # encryption function dec "n" = * -:~&@T ^p(~&,rep"n" ~&zyC)~~K30K31X letters # decryption function   plaintext = 'the five boxing wizards jump quickly THE FIVE BOXING WIZARDS JUMP QUICKLY'   #show+ # exhaustive test   test = ("n". <.enc"n",dec"n"+ enc"n"> plaintext)*= nrange/1 25
http://rosettacode.org/wiki/Box_the_compass
Box the compass
There be many a land lubber that knows naught of the pirate ways and gives direction by degree! They know not how to box the compass! Task description Create a function that takes a heading in degrees and returns the correct 32-point compass heading. Use the function to print and display a table of Index, Compass point, and Degree; rather like the corresponding columns from, the first table of the wikipedia article, but use only the following 33 headings as input: [0.0, 16.87, 16.88, 33.75, 50.62, 50.63, 67.5, 84.37, 84.38, 101.25, 118.12, 118.13, 135.0, 151.87, 151.88, 168.75, 185.62, 185.63, 202.5, 219.37, 219.38, 236.25, 253.12, 253.13, 270.0, 286.87, 286.88, 303.75, 320.62, 320.63, 337.5, 354.37, 354.38]. (They should give the same order of points but are spread throughout the ranges of acceptance). Notes; The headings and indices can be calculated from this pseudocode: for i in 0..32 inclusive: heading = i * 11.25 case i %3: if 1: heading += 5.62; break if 2: heading -= 5.62; break end index = ( i mod 32) + 1 The column of indices can be thought of as an enumeration of the thirty two cardinal points (see talk page)..
#C.2B.2B
C++
#include <string> #include <boost/array.hpp> #include <boost/assign/list_of.hpp> #include <boost/format.hpp> #include <boost/foreach.hpp> #include <iostream> #include <math.h> using std::string; using namespace boost::assign;   int get_Index(float angle) { return static_cast<int>(floor(angle / 11.25 +0.5 )) % 32 + 1; }   string get_Abbr_From_Index(int i) { static boost::array<std::string, 32> points(list_of ("N")("NbE")("NNE")("NEbN")("NE")("NEbE")("ENE")("EbN") ("E")("EbS")("ESE")("SEbE")("SE")("SEbS")("SSE")("SbE") ("S")("SbW")("SSW")("SWbS")("SW")("SWbW")("WSW")("WbS") ("W")("WbN")("WNW")("NWbW")("NW")("NWbN")("NNW")("NbW")); return points[i-1]; }   string Build_Name_From_Abbreviation(string a) { string retval; for (int i = 0; i < a.size(); ++i){ if ((1 == i) && (a[i] != 'b') && (a.size() == 3)) retval += "-"; switch (a[i]){ case 'N' : retval += "north"; break; case 'S' : retval += "south"; break; case 'E' : retval += "east"; break; case 'W' : retval += "west"; break; case 'b' : retval += " by "; break; } } retval[0] = toupper(retval[0]); return retval; }   int main() { boost::array<float,33> headings(list_of (0.0)(16.87)(16.88)(33.75)(50.62)(50.63)(67.5)(84.37)(84.38)(101.25) (118.12)(118.13)(135.0)(151.87)(151.88)(168.75)(185.62)(185.63)(202.5) (219.37)(219.38)(236.25)(253.12)(253.13)(270.0)(286.87)(286.88)(303.75) (320.62)(320.63)(337.5)(354.37)(354.38)); int i; boost::format f("%1$4d %2$-20s %3$_7.2f");   BOOST_FOREACH(float a, headings) { i = get_Index(a); std::cout << f % i % Build_Name_From_Abbreviation(get_Abbr_From_Index(i)) % a << std::endl; } return 0; }
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, where N is the image width and M is the image height. Test task Histogram is useful for many image processing operations. As an example, use it to convert an image into black and white art. The method works as follows: Convert image to grayscale; Compute the histogram Find the median: defined as the luminance such that the image has an approximately equal number of pixels with lesser and greater luminance. Replace each pixel of luminance lesser than the median to black, and others to white. Use read/write ppm file, and grayscale image solutions.
#Raku
Raku
class Pixel { has UInt ($.R, $.G, $.B) } class Bitmap { has UInt ($.width, $.height); has Pixel @.data; }   role PBM { has @.BM; method P4 returns Blob { "P4\n{self.width} {self.height}\n".encode('ascii') ~ Blob.new: self.BM } }   sub getline ( $fh ) { my $line = '#'; # skip comments when reading image file $line = $fh.get while $line.substr(0,1) eq '#'; $line; }   sub load-ppm ( $ppm ) { my $fh = $ppm.IO.open( :enc('ISO-8859-1') ); my $type = $fh.&getline; my ($width, $height) = $fh.&getline.split: ' '; my $depth = $fh.&getline; Bitmap.new( width => $width.Int, height => $height.Int, data => ( $fh.slurp.ords.rotor(3).map: { Pixel.new(R => $_[0], G => $_[1], B => $_[2]) } ) ) }   sub grayscale ( Bitmap $bmp ) { map { (.R*0.2126 + .G*0.7152 + .B*0.0722).round(1) min 255 }, $bmp.data; }   sub histogram ( Bitmap $bmp ) { my @gray = grayscale($bmp); my $threshold = @gray.sum / @gray; for @gray.rotor($bmp.width) { my @row = $_.list; @row.push(0) while @row % 8; $bmp.BM.append: @row.rotor(8).map: { :2(($_ X< $threshold)».Numeric.join) } } }   my $filename = './Lenna.ppm';   my Bitmap $b = load-ppm( $filename ) but PBM;   histogram($b);   './Lenna-bw.pbm'.IO.open(:bin, :w).write: $b.P4;
http://rosettacode.org/wiki/Bitwise_operations
Bitwise operations
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation | Comparison | Matching Memory Operations Pointers & references | Addresses Task Write a routine to perform a bitwise AND, OR, and XOR on two integers, a bitwise NOT on the first integer, a left shift, right shift, right arithmetic shift, left rotate, and right rotate. All shifts and rotates should be done on the first integer with a shift/rotate amount of the second integer. If any operation is not available in your language, note it.
#AppleScript
AppleScript
use AppleScript version "2.4" use framework "Foundation" use scripting additions   -- BIT OPERATIONS FOR APPLESCRIPT (VIA JAVASCRIPT FOR AUTOMATION)   -- bitAND :: Int -> Int -> Int on bitAND(x, y) jsOp2("&", x, y) end bitAND   -- bitOR :: Int -> Int -> Int on bitOR(x, y) jsOp2("|", x, y) end bitOR   -- bitXOr :: Int -> Int -> Int on bitXOR(x, y) jsOp2("^", x, y) end bitXOR   -- bitNOT :: Int -> Int on bitNOT(x) jsOp1("~", x) end bitNOT   -- (<<) :: Int -> Int -> Int on |<<|(x, y) if 31 < y then 0 else jsOp2("<<", x, y) end if end |<<|   -- Logical right shift -- (>>>) :: Int -> Int -> Int on |>>>|(x, y) jsOp2(">>>", x, y) end |>>>|   -- Arithmetic right shift -- (>>) :: Int -> Int -> Int on |>>|(x, y) jsOp2(">>", x, y) end |>>|     -- TEST ---------------------------------------------------------- on run -- Using an ObjC interface to Javascript for Automation   set strClip to bitWise(255, 170) set the clipboard to strClip strClip end run   -- bitWise :: Int -> Int -> String on bitWise(a, b) set labels to {"a AND b", "a OR b", "a XOR b", "NOT a", ¬ "a << b", "a >>> b", "a >> b"} set xs to {bitAND(a, b), bitOR(a, b), bitXOR(a, b), bitNOT(a), ¬ |<<|(a, b), |>>>|(a, b), |>>|(a, b)}   script asBin property arrow : " -> " on |λ|(x, y) justifyRight(8, space, x) & arrow & ¬ justifyRight(14, space, y as text) & arrow & showBinary(y) end |λ| end script   unlines({"32 bit signed integers (in two's complement binary encoding)", "", ¬ unlines(zipWith(asBin, ¬ {"a = " & a as text, "b = " & b as text}, {a, b})), "", ¬ unlines(zipWith(asBin, labels, xs))}) end bitWise   -- CONVERSIONS AND DISPLAY   -- bitsFromInt :: Int -> Either String [Bool] on bitsFromIntLR(x) script go on |λ|(n, d, bools) set xs to {0 ≠ d} & bools if n > 0 then |λ|(n div 2, n mod 2, xs) else xs end if end |λ| end script   set a to abs(x) if (2.147483647E+9) < a then |Left|("Integer overflow – maximum is (2 ^ 31) - 1") else set bs to go's |λ|(a div 2, a mod 2, {}) if 0 > x then |Right|(replicate(32 - (length of bs), true) & ¬ binSucc(map(my |not|, bs))) else set bs to go's |λ|(a div 2, a mod 2, {}) |Right|(replicate(32 - (length of bs), false) & bs) end if end if end bitsFromIntLR   -- Successor function (+1) for unsigned binary integer   -- binSucc :: [Bool] -> [Bool] on binSucc(bs) script succ on |λ|(a, x) if a then if x then Tuple(a, false) else Tuple(x, true) end if else Tuple(a, x) end if end |λ| end script   set tpl to mapAccumR(succ, true, bs) if |1| of tpl then {true} & |2| of tpl else |2| of tpl end if end binSucc   -- showBinary :: Int -> String on showBinary(x) script showBin on |λ|(xs) script bChar on |λ|(b) if b then "1" else "0" end if end |λ| end script   map(bChar, xs) end |λ| end script bindLR(my bitsFromIntLR(x), showBin) end showBinary     -- JXA ------------------------------------------------------------------   --jsOp2 :: String -> a -> b -> c on jsOp2(strOp, a, b) bindLR(evalJSLR(unwords({a as text, strOp, b as text})), my |id|) as integer end jsOp2   --jsOp2 :: String -> a -> b on jsOp1(strOp, a) bindLR(evalJSLR(unwords({strOp, a as text})), my |id|) as integer end jsOp1   -- evalJSLR :: String -> Either String a on evalJSLR(strJS) try -- NB if gJSC is global it must be released -- (e.g. set to null) at end of script gJSC's evaluateScript on error set gJSC to current application's JSContext's new() log ("new JSC") end try set v to unwrap((gJSC's evaluateScript:(strJS))'s toObject()) if v is missing value then |Left|("JS evaluation error") else |Right|(v) end if end evalJSLR   -- GENERIC FUNCTIONS --------------------------------------------------   -- Left :: a -> Either a b on |Left|(x) {type:"Either", |Left|:x, |Right|:missing value} end |Left|   -- Right :: b -> Either a b on |Right|(x) {type:"Either", |Left|:missing value, |Right|:x} end |Right|   -- Tuple (,) :: a -> b -> (a, b) on Tuple(a, b) {type:"Tuple", |1|:a, |2|:b, length:2} end Tuple   -- Absolute value. -- abs :: Num -> Num on abs(x) if 0 > x then -x else x end if end abs   -- bindLR (>>=) :: Either a -> (a -> Either b) -> Either b on bindLR(m, mf) if missing value is not |Right| of m then mReturn(mf)'s |λ|(|Right| of m) else m end if end bindLR   -- foldr :: (a -> b -> b) -> b -> [a] -> b on foldr(f, startValue, xs) tell mReturn(f) set v to startValue set lng to length of xs repeat with i from lng to 1 by -1 set v to |λ|(item i of xs, v, i, xs) end repeat return v end tell end foldr   -- id :: a -> a on |id|(x) x end |id|   -- justifyRight :: Int -> Char -> String -> String on justifyRight(n, cFiller, strText) if n > length of strText then text -n thru -1 of ((replicate(n, cFiller) as text) & strText) else strText end if end justifyRight   -- map :: (a -> b) -> [a] -> [b] on map(f, xs) tell mReturn(f) set lng to length of xs set lst to {} repeat with i from 1 to lng set end of lst to |λ|(item i of xs, i, xs) end repeat return lst end tell end map   -- 'The mapAccumR function behaves like a combination of map and foldr; -- it applies a function to each element of a list, passing an accumulating -- parameter from |Right| to |Left|, and returning a final value of this -- accumulator together with the new list.' (see Hoogle) -- mapAccumR :: (acc -> x -> (acc, y)) -> acc -> [x] -> (acc, [y]) on mapAccumR(f, acc, xs) script on |λ|(x, a, i) tell mReturn(f) to set pair to |λ|(|1| of a, x, i) Tuple(|1| of pair, (|2| of pair) & |2| of a) end |λ| end script foldr(result, Tuple(acc, []), xs) end mapAccumR   -- min :: Ord a => a -> a -> a on min(x, y) if y < x then y else x end if end min   -- Lift 2nd class handler function into 1st class script wrapper -- mReturn :: First-class m => (a -> b) -> m (a -> b) on mReturn(f) if class of f is script then f else script property |λ| : f end script end if end mReturn   -- not :: Bool -> Bool on |not|(p) not p end |not|   -- Egyptian multiplication - progressively doubling a list, appending -- stages of doubling to an accumulator where needed for binary -- assembly of a target length -- replicate :: Int -> a -> [a] on replicate(n, a) set out to {} if n < 1 then return out set dbl to {a}   repeat while (n > 1) if (n mod 2) > 0 then set out to out & dbl set n to (n div 2) set dbl to (dbl & dbl) end repeat return out & dbl end replicate   -- unlines :: [String] -> String on unlines(xs) set {dlm, my text item delimiters} to ¬ {my text item delimiters, linefeed} set str to xs as text set my text item delimiters to dlm str end unlines   -- unwords :: [String] -> String on unwords(xs) set {dlm, my text item delimiters} to {my text item delimiters, space} set s to xs as text set my text item delimiters to dlm return s end unwords   -- unwrap :: NSObject -> a on unwrap(objCValue) if objCValue is missing value then missing value else set ca to current application item 1 of ((ca's NSArray's arrayWithObject:objCValue) as list) end if end unwrap   -- zipWith :: (a -> b -> c) -> [a] -> [b] -> [c] on zipWith(f, xs, ys) set lng to min(length of xs, length of ys) if 1 > lng then return {} set lst to {} tell mReturn(f) repeat with i from 1 to lng set end of lst to |λ|(item i of xs, item i of ys) end repeat return lst end tell end zipWith
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#Python
Python
  #lang racket (require racket/draw)   (define (draw-line dc p q) (match* (p q) [((list x y) (list s t)) (send dc draw-line x y s t)]))   (define (draw-lines dc ps) (void (for/fold ([p0 (first ps)]) ([p (rest ps)]) (draw-line dc p0 p) p)))   (define (int t p q) (define ((int1 t) x0 x1) (+ (* (- 1 t) x0) (* t x1))) (map (int1 t) p q))   (define (bezier-points p0 p1 p2) (for/list ([t (in-range 0.0 1.0 (/ 1.0 20))]) (int t (int t p0 p1) (int t p1 p2))))   (define bm (make-object bitmap% 17 17)) (define dc (new bitmap-dc% [bitmap bm])) (send dc set-smoothing 'unsmoothed) (send dc set-pen "red" 1 'solid) (draw-lines dc (bezier-points '(16 1) '(1 4) '(3 16))) bm  
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#R
R
  #lang racket (require racket/draw)   (define (draw-line dc p q) (match* (p q) [((list x y) (list s t)) (send dc draw-line x y s t)]))   (define (draw-lines dc ps) (void (for/fold ([p0 (first ps)]) ([p (rest ps)]) (draw-line dc p0 p) p)))   (define (int t p q) (define ((int1 t) x0 x1) (+ (* (- 1 t) x0) (* t x1))) (map (int1 t) p q))   (define (bezier-points p0 p1 p2) (for/list ([t (in-range 0.0 1.0 (/ 1.0 20))]) (int t (int t p0 p1) (int t p1 p2))))   (define bm (make-object bitmap% 17 17)) (define dc (new bitmap-dc% [bitmap bm])) (send dc set-smoothing 'unsmoothed) (send dc set-pen "red" 1 'solid) (draw-lines dc (bezier-points '(16 1) '(1 4) '(3 16))) bm  
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#Racket
Racket
  #lang racket (require racket/draw)   (define (draw-line dc p q) (match* (p q) [((list x y) (list s t)) (send dc draw-line x y s t)]))   (define (draw-lines dc ps) (void (for/fold ([p0 (first ps)]) ([p (rest ps)]) (draw-line dc p0 p) p)))   (define (int t p q) (define ((int1 t) x0 x1) (+ (* (- 1 t) x0) (* t x1))) (map (int1 t) p q))   (define (bezier-points p0 p1 p2) (for/list ([t (in-range 0.0 1.0 (/ 1.0 20))]) (int t (int t p0 p1) (int t p1 p2))))   (define bm (make-object bitmap% 17 17)) (define dc (new bitmap-dc% [bitmap bm])) (send dc set-smoothing 'unsmoothed) (send dc set-pen "red" 1 'solid) (draw-lines dc (bezier-points '(16 1) '(1 4) '(3 16))) bm  
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#Raku
Raku
class Pixel { has UInt ($.R, $.G, $.B) } class Bitmap { has UInt ($.width, $.height); has Pixel @!data;   method fill(Pixel $p) { @!data = $p.clone xx ($!width*$!height) } method pixel( $i where ^$!width, $j where ^$!height --> Pixel ) is rw { @!data[$i + $j * $!width] }   method set-pixel ($i, $j, Pixel $p) { return if $j >= $!height; self.pixel($i, $j) = $p.clone; } method get-pixel ($i, $j) returns Pixel { self.pixel($i, $j); }   method line(($x0 is copy, $y0 is copy), ($x1 is copy, $y1 is copy), $pix) { my $steep = abs($y1 - $y0) > abs($x1 - $x0); if $steep { ($x0, $y0) = ($y0, $x0); ($x1, $y1) = ($y1, $x1); } if $x0 > $x1 { ($x0, $x1) = ($x1, $x0); ($y0, $y1) = ($y1, $y0); } my $Δx = $x1 - $x0; my $Δy = abs($y1 - $y0); my $error = 0; my $Δerror = $Δy / $Δx; my $y-step = $y0 < $y1 ?? 1 !! -1; my $y = $y0; for $x0 .. $x1 -> $x { if $steep { self.set-pixel($y, $x, $pix); } else { self.set-pixel($x, $y, $pix); } $error += $Δerror; if $error >= 0.5 { $y += $y-step; $error -= 1.0; } } }   method dot (($px, $py), $pix, $radius = 2) { for $px - $radius .. $px + $radius -> $x { for $py - $radius .. $py + $radius -> $y { self.set-pixel($x, $y, $pix) if ( $px - $x + ($py - $y) * i ).abs <= $radius; } } }   method quadratic ( ($x1, $y1), ($x2, $y2), ($x3, $y3), $pix, $segments = 30 ) { my @line-segments = map -> $t { my \a = (1-$t)²; my \b = $t * (1-$t) * 2; my \c = $t²; (a*$x1 + b*$x2 + c*$x3).round(1),(a*$y1 + b*$y2 + c*$y3).round(1) }, (0, 1/$segments, 2/$segments ... 1); for @line-segments.rotor(2=>-1) -> ($p1, $p2) { self.line( $p1, $p2, $pix) }; }   method data { @!data } }   role PPM { method P6 returns Blob { "P6\n{self.width} {self.height}\n255\n".encode('ascii') ~ Blob.new: flat map { .R, .G, .B }, self.data } }   sub color( $r, $g, $b) { Pixel.new(R => $r, G => $g, B => $b) }   my Bitmap $b = Bitmap.new( width => 600, height => 400) but PPM;   $b.fill( color(2,2,2) );   my @points = (65,25), (85,380), (570,15);   my %seen; my $c = 0; for @points.permutations -> @this { %seen{@this.reverse.join.Str}++; next if %seen{@this.join.Str}; $b.quadratic( |@this, color(255-$c,127,$c+=80) ); }   @points.map: { $b.dot( $_, color(255,0,0), 3 )}   $*OUT.write: $b.P6;
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#Julia
Julia
function drawcircle!(img::Matrix{T}, col::T, x0::Int, y0::Int, radius::Int) where T x = radius - 1 y = 0 δx = δy = 1 er = δx - (radius << 1)   s = x + y while x ≥ y for opx in (+, -), opy in (+, -), el in (x, y) @inbounds img[opx(x0, el) + 1, opy(y0, s - el) + 1] = col end if er ≤ 0 y += 1 er += δy δy += 2 end if er > 0 x -= 1 δx += 2 er += (-radius << 1) + δx end s = x + y end return img end   # Test using Images   img = fill(Gray(255.0), 25, 25); drawcircle!(img, Gray(0.0), 12, 12, 12)
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#Lua
Lua
function Bitmap:circle(x, y, r, c) local dx, dy, err = r, 0, 1-r while dx >= dy do self:set(x+dx, y+dy, c) self:set(x-dx, y+dy, c) self:set(x+dx, y-dy, c) self:set(x-dx, y-dy, c) self:set(x+dy, y+dx, c) self:set(x-dy, y+dx, c) self:set(x+dy, y-dx, c) self:set(x-dy, y-dx, c) dy = dy + 1 if err < 0 then err = err + 2 * dy + 1 else dx, err = dx-1, err + 2 * (dy - dx) + 1 end end end
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#FreeBASIC
FreeBASIC
' version 01-11-2016 ' compile with: fbc -s console   ' translation from Bitmap/Bresenham's line algorithm C entry Sub Br_line(x0 As Integer, y0 As Integer, x1 As Integer, y1 As Integer, _ Col As UInteger = &HFFFFFF)   Dim As Integer dx = Abs(x1 - x0), dy = Abs(y1 - y0) Dim As Integer sx = IIf(x0 < x1, 1, -1) Dim As Integer sy = IIf(y0 < y1, 1, -1) Dim As Integer er = IIf(dx > dy, dx, -dy) \ 2, e2   Do PSet(x0, y0), col If (x0 = x1) And (y0 = y1) Then Exit Do e2 = er If e2 > -dx Then Er -= dy : x0 += sx If e2 < dy Then Er += dx : y0 += sy Loop   End Sub   ' Bitmap/Bézier curves/Cubic BBC BASIC entry Sub beziercubic(x1 As Double, y1 As Double, x2 As Double, y2 As Double, _ x3 As Double, y3 As Double, x4 As Double, y4 As Double, _ n As ULong, col As UInteger = &HFFFFFF)   Type point_ x As Integer y As Integer End Type   Dim As ULong i Dim As Double t, t1, a, b, c, d Dim As point_ p(n)   For i = 0 To n t = i / n t1 = 1 - t a = t1 ^ 3 b = t * t1 * t1 * 3 c = t * t * t1 * 3 d = t ^ 3 p(i).x = Int(a * x1 + b * x2 + c * x3 + d * x4 + .5) p(i).y = Int(a * y1 + b * y2 + c * y3 + d * y4 + .5) Next   For i = 0 To n -1 Br_line(p(i).x, p(i).y, p(i +1).x, p(i +1).y, col) Next   End Sub   ' ------=< MAIN >=------   ScreenRes 250,250,32 ' 0,0 in top left corner   beziercubic(160, 150, 10, 120, 30, 0, 150, 50, 20)     ' empty keyboard buffer While Inkey <> "" : Wend Print : Print "hit any key to end program" Sleep End
http://rosettacode.org/wiki/Biorhythms
Biorhythms
For a while in the late 70s, the pseudoscience of biorhythms was popular enough to rival astrology, with kiosks in malls that would give you your weekly printout. It was also a popular entry in "Things to Do with your Pocket Calculator" lists. You can read up on the history at Wikipedia, but the main takeaway is that unlike astrology, the math behind biorhythms is dead simple. It's based on the number of days since your birth. The premise is that three cycles of unspecified provenance govern certain aspects of everyone's lives – specifically, how they're feeling physically, emotionally, and mentally. The best part is that not only do these cycles somehow have the same respective lengths for all humans of any age, gender, weight, genetic background, etc, but those lengths are an exact number of days. And the pattern is in each case a perfect sine curve. Absolutely miraculous! To compute your biorhythmic profile for a given day, the first thing you need is the number of days between that day and your birth, so the answers in Days between dates are probably a good starting point. (Strictly speaking, the biorhythms start at 0 at the moment of your birth, so if you know time of day you can narrow things down further, but in general these operate at whole-day granularity.) Then take the residue of that day count modulo each of the the cycle lengths to calculate where the day falls on each of the three sinusoidal journeys. The three cycles and their lengths are as follows: Cycle Length Physical 23 days Emotional 28 days Mental 33 days The first half of each cycle is in "plus" territory, with a peak at the quarter-way point; the second half in "minus" territory, with a valley at the three-quarters mark. You can calculate a specific value between -1 and +1 for the kth day of an n-day cycle by computing sin( 2πk / n ). The days where a cycle crosses the axis in either direction are called "critical" days, although with a cycle value of 0 they're also said to be the most neutral, which seems contradictory. The task: write a subroutine, function, or program that will, given a birthdate and a target date, output the three biorhythmic values for the day. You may optionally include a text description of the position and the trend (e.g. "up and rising", "peak", "up but falling", "critical", "down and falling", "valley", "down but rising"), an indication of the date on which the next notable event (peak, valley, or crossing) falls, or even a graph of the cycles around the target date. Demonstrate the functionality for dates of your choice. Example run of my Raku implementation: raku br.raku 1943-03-09 1972-07-11 Output: Day 10717: Physical day 22: -27% (down but rising, next transition 1972-07-12) Emotional day 21: valley Mental day 25: valley Double valley! This was apparently not a good day for Mr. Fischer to begin a chess tournament...
#11l
11l
F biorhythms(birthdate_str, targetdate_str) ‘ Print out biorhythm data for targetdate assuming you were born on birthdate.   birthdate and targetdata are strings in this format:   YYYY-MM-DD e.g. 1964-12-26 ’   print(‘Born: ’birthdate_str‘ Target: ’targetdate_str)   V birthdate = time:strptime(birthdate_str, ‘%Y-%m-%d’) V targetdate = time:strptime(targetdate_str, ‘%Y-%m-%d’)   V days = (targetdate - birthdate).days()   print(‘Day: ’days)   V cycle_labels = [‘Physical’, ‘Emotional’, ‘Mental’] V cycle_lengths = [23, 28, 33] V quadrants = [(‘up and rising’, ‘peak’), (‘up but falling’, ‘transition’), (‘down and falling’, ‘valley’), (‘down but rising’, ‘transition’)]   L(i) 3 V label = cycle_labels[i] V length = cycle_lengths[i] V position = days % length V quadrant = Int(floor((4 * position) / length)) V percentage = Int(round(100 * sin(2 * math:pi * position / length), 0)) V transition_date = (targetdate + TimeDelta(days' floor((quadrant + 1) / 4 * length) - position)).strftime(‘%Y-%m-%d’) V (trend, next) = quadrants[quadrant]   String description I percentage > 95 description = ‘peak’ E I percentage < -95 description = ‘valley’ E I abs(percentage) < 5 description = ‘critical transition’ E description = percentage‘% (’trend‘, next ’next‘ ’transition_date‘)’ print(label‘ day ’position‘: ’description)   biorhythms(‘2043-03-09’, ‘2072-07-11’)
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#Visual_Basic_.NET
Visual Basic .NET
Public Shared Sub SaveRasterBitmapToPpmFile(ByVal rasterBitmap As RasterBitmap, ByVal filepath As String) Dim header As String = String.Format("P6{0}{1}{2}{3}{0}255{0}", vbLf, rasterBitmap.Width, " "c, rasterBitmap.Height) Dim bufferSize As Integer = header.Length + (rasterBitmap.Width * rasterBitmap.Height * 3) Dim bytes(bufferSize - 1) As Byte Buffer.BlockCopy(Encoding.ASCII.GetBytes(header.ToString), 0, bytes, 0, header.Length) Dim index As Integer = header.Length For y As Integer = 0 To rasterBitmap.Height - 1 For x As Integer = 0 To rasterBitmap.Width - 1 Dim color As Rgb = rasterBitmap.GetPixel(x, y) bytes(index) = color.R bytes(index + 1) = color.G bytes(index + 2) = color.B index += 3 Next Next My.Computer.FileSystem.WriteAllBytes(filepath, bytes, False) End Sub
http://rosettacode.org/wiki/Bitmap/Bresenham%27s_line_algorithm
Bitmap/Bresenham's line algorithm
Task Using the data storage type defined on the Bitmap page for raster graphics images, draw a line given two points with Bresenham's line algorithm.
#Ada
Ada
procedure Line (Picture : in out Image; Start, Stop : Point; Color : Pixel) is DX  : constant Float := abs Float (Stop.X - Start.X); DY  : constant Float := abs Float (Stop.Y - Start.Y); Err : Float; X  : Positive := Start.X; Y  : Positive := Start.Y; Step_X : Integer := 1; Step_Y : Integer := 1; begin if Start.X > Stop.X then Step_X := -1; end if; if Start.Y > Stop.Y then Step_Y := -1; end if; if DX > DY then Err := DX / 2.0; while X /= Stop.X loop Picture (X, Y) := Color; Err := Err - DY; if Err < 0.0 then Y := Y + Step_Y; Err := Err + DX; end if; X := X + Step_X; end loop; else Err := DY / 2.0; while Y /= Stop.Y loop Picture (X, Y) := Color; Err := Err - DX; if Err < 0.0 then X := X + Step_X; Err := Err + DY; end if; Y := Y + Step_Y; end loop; end if; Picture (X, Y) := Color; -- Ensure dots to be drawn end Line;
http://rosettacode.org/wiki/Bitcoin/address_validation
Bitcoin/address validation
Bitcoin/address validation You are encouraged to solve this task according to the task description, using any language you may know. Task Write a program that takes a bitcoin address as argument, and checks whether or not this address is valid. A bitcoin address uses a base58 encoding, which uses an alphabet of the characters 0 .. 9, A ..Z, a .. z, but without the four characters:   0   zero   O   uppercase oh   I   uppercase eye   l   lowercase ell With this encoding, a bitcoin address encodes 25 bytes: the first byte is the version number, which will be zero for this task ; the next twenty bytes are a RIPEMD-160 digest, but you don't have to know that for this task: you can consider them a pure arbitrary data ; the last four bytes are a checksum check. They are the first four bytes of a double SHA-256 digest of the previous 21 bytes. To check the bitcoin address, you must read the first twenty-one bytes, compute the checksum, and check that it corresponds to the last four bytes. The program can either return a boolean value or throw an exception when not valid. You can use a digest library for SHA-256. Example of a bitcoin address 1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62i It doesn't belong to anyone and is part of the test suite of the bitcoin software. You can change a few characters in this string and check that it'll fail the test.
#C.23
C#
  using System; using System.Linq; using System.Security.Cryptography; using NUnit.Framework;   namespace BitcoinValidator { public class ValidateTest { [TestCase] public void ValidateBitcoinAddressTest() { Assert.IsTrue(ValidateBitcoinAddress("1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62i")); // VALID Assert.IsTrue(ValidateBitcoinAddress("1Q1pE5vPGEEMqRcVRMbtBK842Y6Pzo6nK9")); // VALID Assert.Throws<Exception>(() => ValidateBitcoinAddress("1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62X")); // checksum changed, original data Assert.Throws<Exception>(() => ValidateBitcoinAddress("1ANNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62i")); // data changed, original checksum Assert.Throws<Exception>(() => ValidateBitcoinAddress("1A Na15ZQXAZUgFiqJ2i7Z2DPU2J6hW62i")); // invalid chars Assert.Throws<Exception>(() => ValidateBitcoinAddress("BZbvjr")); // checksum is fine, address too short }   public static bool ValidateBitcoinAddress(string address) { if (address.Length < 26 || address.Length > 35) throw new Exception("wrong length"); var decoded = DecodeBase58(address); var d1 = Hash(decoded.SubArray(0, 21)); var d2 = Hash(d1); if (!decoded.SubArray(21, 4).SequenceEqual(d2.SubArray(0, 4))) throw new Exception("bad digest"); return true; }   const string Alphabet = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"; const int Size = 25;   private static byte[] DecodeBase58(string input) { var output = new byte[Size]; foreach (var t in input) { var p = Alphabet.IndexOf(t); if (p == -1) throw new Exception("invalid character found"); var j = Size; while (--j > 0) { p += 58 * output[j]; output[j] = (byte)(p % 256); p /= 256; } if (p != 0) throw new Exception("address too long"); } return output; }   private static byte[] Hash(byte[] bytes) { var hasher = new SHA256Managed(); return hasher.ComputeHash(bytes); } }   public static class ArrayExtensions { public static T[] SubArray<T>(this T[] data, int index, int length) { var result = new T[length]; Array.Copy(data, index, result, 0, length); return result; } } }  
http://rosettacode.org/wiki/Bitcoin/public_point_to_address
Bitcoin/public point to address
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion. The encoding steps are: take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed string ; add one byte prefix equal to 4 (it is a convention for this way of encoding a public point) ; compute the SHA-256 of this string ; compute the RIPEMD-160 of this SHA-256 digest ; compute the checksum of the concatenation of the version number digit (a single zero byte) and this RIPEMD-160 digest, as described in bitcoin/address validation ; Base-58 encode (see below) the concatenation of the version number (zero in this case), the ripemd digest and the checksum The base-58 encoding is based on an alphabet of alphanumeric characters (numbers, upper case and lower case, in that order) but without the four characters 0, O, l and I. Here is an example public point: X = 0x50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352 Y = 0x2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6 The corresponding address should be: 16UwLL9Risc3QfPqBUvKofHmBQ7wMtjvM Nb. The leading '1' is not significant as 1 is zero in base-58. It is however often added to the bitcoin address for various reasons. There can actually be several of them. You can ignore this and output an address without the leading 1. Extra credit: add a verification procedure about the public point, making sure it belongs to the secp256k1 elliptic curve
#Haskell
Haskell
import Numeric (showIntAtBase) import Data.List (unfoldr) import Data.Binary (Word8) import Crypto.Hash.SHA256 as S (hash) import Crypto.Hash.RIPEMD160 as R (hash) import Data.ByteString (unpack, pack)   publicPointToAddress :: Integer -> Integer -> String publicPointToAddress x y = let toBytes x = reverse $ unfoldr (\b -> if b == 0 then Nothing else Just (fromIntegral $ b `mod` 256, b `div` 256)) x ripe = 0 : unpack (R.hash $ S.hash $ pack $ 4 : toBytes x ++ toBytes y) ripe_checksum = take 4 $ unpack $ S.hash $ S.hash $ pack ripe addressAsList = ripe ++ ripe_checksum address = foldl (\v b -> v * 256 + fromIntegral b) 0 addressAsList base58Digits = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz" in showIntAtBase 58 (base58Digits !!) address ""   main = print $ publicPointToAddress 0x50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352 0x2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6  
http://rosettacode.org/wiki/Bitcoin/public_point_to_address
Bitcoin/public point to address
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion. The encoding steps are: take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed string ; add one byte prefix equal to 4 (it is a convention for this way of encoding a public point) ; compute the SHA-256 of this string ; compute the RIPEMD-160 of this SHA-256 digest ; compute the checksum of the concatenation of the version number digit (a single zero byte) and this RIPEMD-160 digest, as described in bitcoin/address validation ; Base-58 encode (see below) the concatenation of the version number (zero in this case), the ripemd digest and the checksum The base-58 encoding is based on an alphabet of alphanumeric characters (numbers, upper case and lower case, in that order) but without the four characters 0, O, l and I. Here is an example public point: X = 0x50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352 Y = 0x2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6 The corresponding address should be: 16UwLL9Risc3QfPqBUvKofHmBQ7wMtjvM Nb. The leading '1' is not significant as 1 is zero in base-58. It is however often added to the bitcoin address for various reasons. There can actually be several of them. You can ignore this and output an address without the leading 1. Extra credit: add a verification procedure about the public point, making sure it belongs to the secp256k1 elliptic curve
#Julia
Julia
const digits = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz" function encodebase58(b::Vector{<:Integer}) out = Vector{Char}(34) for j in endof(out):-1:1 local c::Int = 0 for i in eachindex(b) c = c * 256 + b[i] b[i] = c ÷ 58 c %= 58 end out[j] = digits[c + 1] end local i = 1 while i < endof(out) && out[i] == '1' i += 1 end return join(out[i:end]) end   const COINVER = 0x00 function pubpoint2address(x::Vector{UInt8}, y::Vector{UInt8}) c = vcat(0x04, x, y) c = vcat(COINVER, digest("ripemd160", sha256(c))) d = sha256(sha256(c)) return encodebase58(vcat(c, d[1:4])) end pubpoint2address(x::AbstractString, y::AbstractString) = pubpoint2address(hex2bytes(x), hex2bytes(y))
http://rosettacode.org/wiki/Bitmap/Flood_fill
Bitmap/Flood fill
Implement a flood fill. A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point towards the banks (or: inside the valley): if there's a hole in the banks, the flood is not contained and all the image (or all the "connected valleys") get filled. To accomplish the task, you need to implement just one of the possible algorithms (examples are on Wikipedia). Variations on the theme are allowed (e.g. adding a tolerance parameter or argument for color-matching of the banks or target color). Testing: the basic algorithm is not suitable for truecolor images; a possible test image is the one shown on the right box; you can try to fill the white area, or the black inner circle.
#E
E
def floodFill(image, x, y, newColor) { def matchColor := image[x, y] def w := image.width() def h := image.height()   /** For any given pixel x,y, this algorithm first fills a contiguous horizontal line segment of pixels containing that pixel, then recursively scans the two adjacent rows over the same horizontal interval. Let this be invocation 0, and the immediate recursive invocations be 1, 2, 3, ..., # be pixels of the wrong color, and * be where each scan starts; the fill ordering is as follows:   --------------##########------- -...1111111111*11####*33333...- ###########000*000000000000...- -...2222222222*22222##*4444...- --------------------##---------   Each invocation returns the x coordinate of the rightmost pixel it filled, or x0 if none were.   Since it is recursive, this algorithm is unsuitable for large images with small stacks. */ def fillScan(var x0, y) { if (y >= 0 && y < h && x0 >= 0 && x0 < w) { image[x0, y] := newColor var x1 := x0   # Fill rightward while (x1 < w - 1 && image.test(x1 + 1, y, matchColor)) { x1 += 1 image[x1, y] := newColor # This could be replaced with a horizontal-line drawing operation }   # Fill leftward while (x0 > 0 && image.test(x0 - 1, y, matchColor)) { x0 -= 1 image[x0, y] := newColor }   if (x0 > x1) { return x0 } # Filled at most center   # x0..x1 is now a run of newly-filled pixels.   # println(`Filled $y $x0..$x1`) # println(image)   # Scan the lines above and below for ynext in [y - 1, y + 1] { if (ynext >= 0 && ynext < h) { var x := x0 while (x <= x1) { if (image.test(x, ynext, matchColor)) { x := fillScan(x, ynext) } x += 1 } } }   return x1 } else { return x0 } }   fillScan(x, y) }
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#Elm
Elm
  --True and False directly represent Boolean values in Elm --For eg to show yes for true and no for false if True then "yes" else "no"   --Same expression differently if False then "no" else "yes"   --This you can run as a program --Elm allows you to take anything you want for representation --In the program we take T for true F for false import Html exposing(text,div,Html) import Html.Attributes exposing(style)   type Expr = T | F | And Expr Expr | Or Expr Expr | Not Expr   evaluate : Expr->Bool evaluate expression = case expression of T -> True   F -> False   And expr1 expr2 -> evaluate expr1 && evaluate expr2   Or expr1 expr2 -> evaluate expr1 || evaluate expr2   Not expr -> not (evaluate expr)   --CHECKING RANDOM LOGICAL EXPRESSIONS ex1= Not F ex2= And T F ex3= And (Not(Or T F)) T   main = div [] (List.map display [ex1, ex2, ex3])   display expr= div [] [ text ( toString expr ++ "-->" ++ toString(evaluate expr) ) ] --END
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#Emacs_Lisp
Emacs Lisp
1> 1 < 2. true 2> 1 < 1. false 3> 0 == false. false
http://rosettacode.org/wiki/Caesar_cipher
Caesar cipher
Task Implement a Caesar cipher, both encoding and decoding. The key is an integer from 1 to 25. This cipher rotates (either towards left or right) the letters of the alphabet (A to Z). The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A). So key 2 encrypts "HI" to "JK", but key 20 encrypts "HI" to "BC". This simple "mono-alphabetic substitution cipher" provides almost no security, because an attacker who has the encoded message can either use frequency analysis to guess the key, or just try all 25 keys. Caesar cipher is identical to Vigenère cipher with a key of length 1. Also, Rot-13 is identical to Caesar cipher with key 13. Related tasks Rot-13 Substitution Cipher Vigenère Cipher/Cryptanalysis
#Vala
Vala
static void println(string str) { stdout.printf("%s\r\n", str); }   static unichar encrypt_char(unichar ch, int code) { if (!ch.isalpha()) return ch;   unichar offset = ch.isupper() ? 'A' : 'a'; return (unichar)((ch + code - offset) % 26 + offset); }   static string encrypt(string input, int code) { var builder = new StringBuilder();   unichar c; for (int i = 0; input.get_next_char(ref i, out c);) { builder.append_unichar(encrypt_char(c, code)); }   return builder.str; }   static string decrypt(string input, int code) { return encrypt(input, 26 - code); }   const string test_case = "The quick brown fox jumped over the lazy dog";   void main() { println(test_case); println(encrypt(test_case, -1)); println(decrypt(encrypt(test_case, -1), -1)); }
http://rosettacode.org/wiki/Box_the_compass
Box the compass
There be many a land lubber that knows naught of the pirate ways and gives direction by degree! They know not how to box the compass! Task description Create a function that takes a heading in degrees and returns the correct 32-point compass heading. Use the function to print and display a table of Index, Compass point, and Degree; rather like the corresponding columns from, the first table of the wikipedia article, but use only the following 33 headings as input: [0.0, 16.87, 16.88, 33.75, 50.62, 50.63, 67.5, 84.37, 84.38, 101.25, 118.12, 118.13, 135.0, 151.87, 151.88, 168.75, 185.62, 185.63, 202.5, 219.37, 219.38, 236.25, 253.12, 253.13, 270.0, 286.87, 286.88, 303.75, 320.62, 320.63, 337.5, 354.37, 354.38]. (They should give the same order of points but are spread throughout the ranges of acceptance). Notes; The headings and indices can be calculated from this pseudocode: for i in 0..32 inclusive: heading = i * 11.25 case i %3: if 1: heading += 5.62; break if 2: heading -= 5.62; break end index = ( i mod 32) + 1 The column of indices can be thought of as an enumeration of the thirty two cardinal points (see talk page)..
#Clojure
Clojure
(ns boxing-the-compass (:use [clojure.string :only [capitalize]]))   (def headings (for [i (range 0 (inc 32))] (let [heading (* i 11.25)] (case (mod i 3) 1 (+ heading 5.62) 2 (- heading 5.62) heading))))   (defn angle2compass [angle] (let [dirs ["N" "NbE" "N-NE" "NEbN" "NE" "NEbE" "E-NE" "EbN" "E" "EbS" "E-SE" "SEbE" "SE" "SEbS" "S-SE" "SbE" "S" "SbW" "S-SW" "SWbS" "SW" "SWbW" "W-SW" "WbS" "W" "WbN" "W-NW" "NWbW" "NW" "NWbN" "N-NW" "NbW"] unpack {\N "north" \E "east" \W "west" \S "south" \b " by " \- "-"} sep (/ 360 (count dirs)) dir (int (/ (mod (+ angle (/ sep 2)) 360) sep))] (capitalize (apply str (map unpack (dirs dir))))))   (print (apply str (map-indexed #(format "%2s %-18s %7.2f\n" (inc (mod %1 32)) (angle2compass %2) %2) headings)))
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, where N is the image width and M is the image height. Test task Histogram is useful for many image processing operations. As an example, use it to convert an image into black and white art. The method works as follows: Convert image to grayscale; Compute the histogram Find the median: defined as the luminance such that the image has an approximately equal number of pixels with lesser and greater luminance. Replace each pixel of luminance lesser than the median to black, and others to white. Use read/write ppm file, and grayscale image solutions.
#Ruby
Ruby
class Pixmap def histogram histogram = Hash.new(0) @height.times do |y| @width.times do |x| histogram[self[x,y].luminosity] += 1 end end histogram end   def to_blackandwhite hist = histogram   # find the median luminosity median = nil sum = 0 hist.keys.sort.each do |lum| sum += hist[lum] if sum > @height * @width / 2 median = lum break end end   # create the black and white image bw = self.class.new(@width, @height) @height.times do |y| @width.times do |x| bw[x,y] = self[x,y].luminosity < median ? RGBColour::BLACK : RGBColour::WHITE end end bw end   def save_as_blackandwhite(filename) to_blackandwhite.save(filename) end end   Pixmap.open('file.ppm').save_as_blackandwhite('file_bw.ppm')
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, where N is the image width and M is the image height. Test task Histogram is useful for many image processing operations. As an example, use it to convert an image into black and white art. The method works as follows: Convert image to grayscale; Compute the histogram Find the median: defined as the luminance such that the image has an approximately equal number of pixels with lesser and greater luminance. Replace each pixel of luminance lesser than the median to black, and others to white. Use read/write ppm file, and grayscale image solutions.
#Rust
Rust
extern crate image; use image::{DynamicImage, GenericImageView, ImageBuffer, Rgba};   /// index of the alpha channel in RGBA const ALPHA: usize = 3;   /// Computes the luminance of a single pixel /// Result lies within `u16::MIN..u16::MAX` const fn luminance(rgba: Rgba<u8>) -> u16 { let Rgba([r, g, b, _a]) = rgba; 55 * r as u16 + 183 * g as u16 + 19 * b as u16 }   /// computes the median of a given histogram /// Result lies within `u16::MIN..u16::MAX` fn get_median(total: usize, histogram: &[usize]) -> u16 { let mut sum = 0; for (index, &count) in histogram.iter().enumerate() { sum += count; if sum >= total / 2 { return index as u16; } }   u16::MAX }   /// computes the histogram of a given image fn compute_histogram(img: &DynamicImage) -> Vec<usize> { let mut histogram = vec![0; 1 << u16::BITS];   img.pixels() .map(|(_x, _y, pixel)| luminance(pixel)) .for_each(|luminance| histogram[luminance as usize] += 1);   histogram }   /// returns a black or white pixel with an alpha value const fn black_white(is_white: bool, alpha: u8) -> [u8; 4] { if is_white { [255, 255, 255, alpha] } else { [0, 0, 0, alpha] } }   /// create a monochome compy of the given image /// preserves alpha data fn convert_to_monochrome(img: &DynamicImage) -> ImageBuffer<Rgba<u8>, Vec<u8>> { let histogram = compute_histogram(img);   let (width, height) = img.dimensions(); let pixel_count = (width * height) as usize; let median = get_median(pixel_count, &histogram);   let pixel_buffer = img.pixels() .flat_map(|(_x, _y, pixel)| black_white(luminance(pixel) > median, pixel[ALPHA])) .collect();   ImageBuffer::from_vec(width, height, pixel_buffer).unwrap_or_else(|| unreachable!()) }   fn main() { let img = image::open("lena.jpg").expect("could not load image file"); let img = convert_to_monochrome(&img); img.save("lena-mono.png").expect("could not save result image"); }  
http://rosettacode.org/wiki/Bitwise_operations
Bitwise operations
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation | Comparison | Matching Memory Operations Pointers & references | Addresses Task Write a routine to perform a bitwise AND, OR, and XOR on two integers, a bitwise NOT on the first integer, a left shift, right shift, right arithmetic shift, left rotate, and right rotate. All shifts and rotates should be done on the first integer with a shift/rotate amount of the second integer. If any operation is not available in your language, note it.
#ARM_Assembly
ARM Assembly
    /* ARM assembly Raspberry PI */ /* program binarydigit.s */ /* Constantes */ .equ STDOUT, 1 .equ WRITE, 4 .equ EXIT, 1 /* Initialized data */ .data szMessResultAnd: .asciz "Result of And : \n" szMessResultOr: .asciz "Result of Or : \n" szMessResultEor: .asciz "Result of Exclusif Or : \n" szMessResultNot: .asciz "Result of Not : \n" szMessResultLsl: .asciz "Result of left shift : \n" szMessResultLsr: .asciz "Result of right shift : \n" szMessResultAsr: .asciz "Result of Arithmetic right shift : \n" szMessResultRor: .asciz "Result of rotate right : \n" szMessResultRrx: .asciz "Result of rotate right with extend : \n" szMessResultClear: .asciz "Result of Bit Clear : \n"   sMessAffBin: .ascii "Register value : " sZoneBin: .space 36,' ' .asciz "\n"   /* code section */ .text .global main main: /* entry of program */ push {fp,lr} /* save des 2 registres */ ldr r0,iAdrszMessResultAnd bl affichageMess mov r0,#5 and r0,#15 bl affichage2 ldr r0,iAdrszMessResultOr bl affichageMess mov r0,#5 orr r0,#15 bl affichage2 ldr r0,iAdrszMessResultEor bl affichageMess mov r0,#5 eor r0,#15 bl affichage2 ldr r0,iAdrszMessResultNot bl affichageMess mov r0,#5 mvn r0,r0 bl affichage2 ldr r0,iAdrszMessResultLsl bl affichageMess mov r0,#5 lsl r0,#1 bl affichage2 ldr r0,iAdrszMessResultLsr bl affichageMess mov r0,#5 lsr r0,#1 bl affichage2 ldr r0,iAdrszMessResultAsr bl affichageMess mov r0,#-5 bl affichage2 mov r0,#-5 asr r0,#1 bl affichage2 ldr r0,iAdrszMessResultRor bl affichageMess mov r0,#5 ror r0,#1 bl affichage2 ldr r0,iAdrszMessResultRrx bl affichageMess mov r0,#5 mov r1,#15 rrx r0,r1 bl affichage2 ldr r0,iAdrszMessResultClear bl affichageMess mov r0,#5 bic r0,#0b100 @ clear 3ieme bit bl affichage2 bic r0,#4 @ clear 3ieme bit ( 4 = 100 binary) bl affichage2   100: /* standard end of the program */ mov r0, #0 @ return code pop {fp,lr} @restaur 2 registers mov r7, #EXIT @ request to exit program swi 0 @ perform the system call iAdrszMessResultAnd: .int szMessResultAnd iAdrszMessResultOr: .int szMessResultOr iAdrszMessResultEor: .int szMessResultEor iAdrszMessResultNot: .int szMessResultNot iAdrszMessResultLsl: .int szMessResultLsl iAdrszMessResultLsr: .int szMessResultLsr iAdrszMessResultAsr: .int szMessResultAsr iAdrszMessResultRor: .int szMessResultRor iAdrszMessResultRrx: .int szMessResultRrx iAdrszMessResultClear: .int szMessResultClear /******************************************************************/ /* register display in binary */ /******************************************************************/ /* r0 contains the register */ affichage2: push {r0,lr} /* save registers */ push {r1-r5} /* save others registers */ mrs r5,cpsr /* saves state register in r5 */ ldr r1,iAdrsZoneBin mov r2,#0 @ read bit position counter mov r3,#0 @ position counter of the written character 1: @ loop lsls r0,#1 @ left shift with flags movcc r4,#48 @ flag carry off character '0' movcs r4,#49 @ flag carry on character '1' strb r4,[r1,r3] @ character -> display zone add r2,r2,#1 @ + 1 read bit position counter add r3,r3,#1 @ + 1 position counter of the written character cmp r2,#8 @ 8 bits read addeq r3,r3,#1 @ + 1 position counter of the written character cmp r2,#16 @ etc addeq r3,r3,#1 cmp r2,#24 addeq r3,r3,#1 cmp r2,#31 @ 32 bits shifted ? ble 1b @ no -> loop   ldr r0,iAdrsZoneMessBin @ address of message result bl affichageMess @ display result   100: msr cpsr,r5 /*restaur state register */ pop {r1-r5} /* restaur others registers */ pop {r0,lr} bx lr iAdrsZoneBin: .int sZoneBin iAdrsZoneMessBin: .int sMessAffBin   /******************************************************************/ /* display text with size calculation */ /******************************************************************/ /* r0 contains the address of the message */ affichageMess: push {fp,lr} /* save registres */ push {r0,r1,r2,r7} /* save others registres */ mov r2,#0 /* counter length */ 1: /* loop length calculation */ ldrb r1,[r0,r2] /* read octet start position + index */ cmp r1,#0 /* if 0 its over */ addne r2,r2,#1 /* else add 1 in the length */ bne 1b /* and loop */ /* so here r2 contains the length of the message */ mov r1,r0 /* address message in r1 */ mov r0,#STDOUT /* code to write to the standard output Linux */ mov r7, #WRITE /* code call system write */ swi #0 /* call systeme */ pop {r0,r1,r2,r7} /* restaur others registres */ pop {fp,lr} /* restaur des 2 registres */ bx lr /* return */      
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#Ruby
Ruby
Define cubic(p1,p2,p3,segs) = Prgm Local i,t,u,prev,pt 0 → pt For i,1,segs+1 (i-1.0)/segs → t © Decimal to avoid slow exact arithetic (1-t) → u pt → prev u^2*p1 + 2*t*u*p2 + t^2*p3 → pt If i>1 Then PxlLine floor(prev[1,1]), floor(prev[1,2]), floor(pt[1,1]), floor(pt[1,2]) EndIf EndFor EndPrgm
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#Tcl
Tcl
Define cubic(p1,p2,p3,segs) = Prgm Local i,t,u,prev,pt 0 → pt For i,1,segs+1 (i-1.0)/segs → t © Decimal to avoid slow exact arithetic (1-t) → u pt → prev u^2*p1 + 2*t*u*p2 + t^2*p3 → pt If i>1 Then PxlLine floor(prev[1,1]), floor(prev[1,2]), floor(pt[1,1]), floor(pt[1,2]) EndIf EndFor EndPrgm
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#TI-89_BASIC
TI-89 BASIC
Define cubic(p1,p2,p3,segs) = Prgm Local i,t,u,prev,pt 0 → pt For i,1,segs+1 (i-1.0)/segs → t © Decimal to avoid slow exact arithetic (1-t) → u pt → prev u^2*p1 + 2*t*u*p2 + t^2*p3 → pt If i>1 Then PxlLine floor(prev[1,1]), floor(prev[1,2]), floor(pt[1,1]), floor(pt[1,2]) EndIf EndFor EndPrgm
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#Vedit_macro_language
Vedit macro language
// Daw a Cubic bezier curve // #20, #30 = Start point // #21, #31 = Control point 1 // #22, #32 = Control point 2 // #23, #33 = end point // #40 = depth of recursion   :CUBIC_BEZIER: if (#40 > 0) { #24 = (#20+#21)/2; #34 = (#30+#31)/2 #26 = (#22+#23)/2; #36 = (#32+#33)/2 #27 = (#20+#21*2+#22)/4; #37 = (#30+#31*2+#32)/4 #28 = (#21+#22*2+#23)/4; #38 = (#31+#32*2+#33)/4 #29 = (#20+#21*3+#22*3+#23)/8; #39 = (#30+#31*3+#32*3+#33)/8 Num_Push(20,40) #21 = #24; #31 = #34 // control 1 #22 = #27; #32 = #37 // control 2 #23 = #29; #33 = #39 // end point #40-- Call("CUBIC_BEZIER") // Draw "left" part Num_Pop(20,40) Num_Push(20,40) #20 = #29; #30 = #39 // start point #21 = #28; #31 = #38 // control 1 #22 = #26; #32 = #36 // control 2 #40-- Call("CUBIC_BEZIER") // Draw "right" part Num_Pop(20,40) } else { #1=#20; #2=#30; #3=#23; #4=#33 Call("DRAW_LINE") } return
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#Kotlin
Kotlin
// version 1.1.4-3   import java.awt.Color import java.awt.Graphics import java.awt.image.BufferedImage import javax.swing.JOptionPane import javax.swing.JLabel import javax.swing.ImageIcon   class BasicBitmapStorage(width: Int, height: Int) { val image = BufferedImage(width, height, BufferedImage.TYPE_3BYTE_BGR)   fun fill(c: Color) { val g = image.graphics g.color = c g.fillRect(0, 0, image.width, image.height) }   fun setPixel(x: Int, y: Int, c: Color) = image.setRGB(x, y, c.getRGB())   fun getPixel(x: Int, y: Int) = Color(image.getRGB(x, y)) }   fun drawCircle(bbs: BasicBitmapStorage, centerX: Int, centerY: Int, radius: Int, circleColor: Color) { var d = (5 - radius * 4) / 4 var x = 0 var y = radius   do { with(bbs) { setPixel(centerX + x, centerY + y, circleColor) setPixel(centerX + x, centerY - y, circleColor) setPixel(centerX - x, centerY + y, circleColor) setPixel(centerX - x, centerY - y, circleColor) setPixel(centerX + y, centerY + x, circleColor) setPixel(centerX + y, centerY - x, circleColor) setPixel(centerX - y, centerY + x, circleColor) setPixel(centerX - y, centerY - x, circleColor) } if (d < 0) { d += 2 * x + 1 } else { d += 2 * (x - y) + 1 y-- } x++ } while (x <= y) }   fun main(args: Array<String>) { val bbs = BasicBitmapStorage(400, 400) bbs.fill(Color.pink) drawCircle(bbs, 200, 200, 100, Color.black) drawCircle(bbs, 200, 200, 50, Color.white) val label = JLabel(ImageIcon(bbs.image)) val title = "Bresenham's circle algorithm" JOptionPane.showMessageDialog(null, label, title, JOptionPane.PLAIN_MESSAGE) }
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#Go
Go
package raster   const b3Seg = 30   func (b *Bitmap) Bézier3(x1, y1, x2, y2, x3, y3, x4, y4 int, p Pixel) { var px, py [b3Seg + 1]int fx1, fy1 := float64(x1), float64(y1) fx2, fy2 := float64(x2), float64(y2) fx3, fy3 := float64(x3), float64(y3) fx4, fy4 := float64(x4), float64(y4) for i := range px { d := float64(i) / b3Seg a := 1 - d b, c := a * a, d * d a, b, c, d = a*b, 3*b*d, 3*a*c, c*d px[i] = int(a*fx1 + b*fx2 + c*fx3 + d*fx4) py[i] = int(a*fy1 + b*fy2 + c*fy3 + d*fy4) } x0, y0 := px[0], py[0] for i := 1; i <= b3Seg; i++ { x1, y1 := px[i], py[i] b.Line(x0, y0, x1, y1, p) x0, y0 = x1, y1 } }   func (b *Bitmap) Bézier3Rgb(x1, y1, x2, y2, x3, y3, x4, y4 int, c Rgb) { b.Bézier3(x1, y1, x2, y2, x3, y3, x4, y4, c.Pixel()) }
http://rosettacode.org/wiki/Biorhythms
Biorhythms
For a while in the late 70s, the pseudoscience of biorhythms was popular enough to rival astrology, with kiosks in malls that would give you your weekly printout. It was also a popular entry in "Things to Do with your Pocket Calculator" lists. You can read up on the history at Wikipedia, but the main takeaway is that unlike astrology, the math behind biorhythms is dead simple. It's based on the number of days since your birth. The premise is that three cycles of unspecified provenance govern certain aspects of everyone's lives – specifically, how they're feeling physically, emotionally, and mentally. The best part is that not only do these cycles somehow have the same respective lengths for all humans of any age, gender, weight, genetic background, etc, but those lengths are an exact number of days. And the pattern is in each case a perfect sine curve. Absolutely miraculous! To compute your biorhythmic profile for a given day, the first thing you need is the number of days between that day and your birth, so the answers in Days between dates are probably a good starting point. (Strictly speaking, the biorhythms start at 0 at the moment of your birth, so if you know time of day you can narrow things down further, but in general these operate at whole-day granularity.) Then take the residue of that day count modulo each of the the cycle lengths to calculate where the day falls on each of the three sinusoidal journeys. The three cycles and their lengths are as follows: Cycle Length Physical 23 days Emotional 28 days Mental 33 days The first half of each cycle is in "plus" territory, with a peak at the quarter-way point; the second half in "minus" territory, with a valley at the three-quarters mark. You can calculate a specific value between -1 and +1 for the kth day of an n-day cycle by computing sin( 2πk / n ). The days where a cycle crosses the axis in either direction are called "critical" days, although with a cycle value of 0 they're also said to be the most neutral, which seems contradictory. The task: write a subroutine, function, or program that will, given a birthdate and a target date, output the three biorhythmic values for the day. You may optionally include a text description of the position and the trend (e.g. "up and rising", "peak", "up but falling", "critical", "down and falling", "valley", "down but rising"), an indication of the date on which the next notable event (peak, valley, or crossing) falls, or even a graph of the cycles around the target date. Demonstrate the functionality for dates of your choice. Example run of my Raku implementation: raku br.raku 1943-03-09 1972-07-11 Output: Day 10717: Physical day 22: -27% (down but rising, next transition 1972-07-12) Emotional day 21: valley Mental day 25: valley Double valley! This was apparently not a good day for Mr. Fischer to begin a chess tournament...
#C
C
#include <stdio.h> #include <stdlib.h> #include <math.h>   int day(int y, int m, int d) { return 367 * y - 7 * (y + (m + 9) / 12) / 4 + 275 * m / 9 + d - 730530; }   void cycle(int diff, int l, char *t) { int p = round(100 * sin(2 * M_PI * diff / l)); printf("%12s cycle: %3i%%", t, p); if (abs(p) < 15) printf(" (critical day)"); printf("\n"); }   int main(int argc, char *argv[]) { int diff;   if (argc < 7) { printf("Usage:\n"); printf("cbio y1 m1 d1 y2 m2 d2\n"); exit(1); } diff = abs(day(atoi(argv[1]), atoi(argv[2]), atoi(argv[3])) - day(atoi(argv[4]), atoi(argv[5]), atoi(argv[6]))); printf("Age: %u days\n", diff); cycle(diff, 23, "Physical"); cycle(diff, 28, "Emotional"); cycle(diff, 33, "Intellectual"); }
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#Wren
Wren
import "graphics" for Canvas, ImageData, Color import "dome" for Window, Process import "io" for FileSystem   class Bitmap { construct new(name, width, height) { Window.title = name Window.resize(width, height) Canvas.resize(width, height) _bmp = ImageData.create(name, width, height) // create bitmap for (y in 0...height) { for (x in 0...width) { var c = Color.rgb(x % 256, y % 256, (x * y) % 256) pset(x, y, c) } } _w = width _h = height }   init() { // write bitmap to a PPM file var ppm = "P6\n%(_w) %(_h)\n255\n" for (y in 0..._h) { for (x in 0..._w) { var c = pget(x, y) ppm = ppm + String.fromByte(c.r) ppm = ppm + String.fromByte(c.g) ppm = ppm + String.fromByte(c.b) } } FileSystem.save("output.ppm", ppm) Process.exit(0) }   pset(x, y, col) { _bmp.pset(x, y, col) }   pget(x, y) { _bmp.pget(x, y) }   update() {}   draw(alpha) {} }   var Game = Bitmap.new("Bitmap - write to PPM file", 320, 320)
http://rosettacode.org/wiki/Bitmap/Bresenham%27s_line_algorithm
Bitmap/Bresenham's line algorithm
Task Using the data storage type defined on the Bitmap page for raster graphics images, draw a line given two points with Bresenham's line algorithm.
#ALGOL_68
ALGOL 68
# -*- coding: utf-8 -*- #   line OF class image := (REF IMAGE picture, POINT start, stop, PIXEL color)VOID: BEGIN REAL dx = ABS (x OF stop - x OF start), dy = ABS (y OF stop - y OF start); REAL err; POINT here := start, step := (1, 1); IF x OF start > x OF stop THEN x OF step := -1 FI; IF y OF start > y OF stop THEN y OF step := -1 FI; IF dx > dy THEN err := dx / 2; WHILE x OF here /= x OF stop DO picture[x OF here, y OF here] := color; err -:= dy; IF err < 0 THEN y OF here +:= y OF step; err +:= dx FI; x OF here +:= x OF step OD ELSE err := dy / 2; WHILE y OF here /= y OF stop DO picture[x OF here, y OF here] := color; err -:= dx; IF err < 0 THEN x OF here +:= x OF step; err +:= dy FI; y OF here +:= y OF step OD FI; picture[x OF here, y OF here] := color # ensure dots to be drawn # END # line #;   SKIP
http://rosettacode.org/wiki/Bioinformatics/Sequence_mutation
Bioinformatics/Sequence mutation
Task Given a string of characters A, C, G, and T representing a DNA sequence write a routine to mutate the sequence, (string) by: Choosing a random base position in the sequence. Mutate the sequence by doing one of either: Swap the base at that position by changing it to one of A, C, G, or T. (which has a chance of swapping the base for the same base) Delete the chosen base at the position. Insert another base randomly chosen from A,C, G, or T into the sequence at that position. Randomly generate a test DNA sequence of at least 200 bases "Pretty print" the sequence and a count of its size, and the count of each base in the sequence Mutate the sequence ten times. "Pretty print" the sequence after all mutations, and a count of its size, and the count of each base in the sequence. Extra credit Give more information on the individual mutations applied. Allow mutations to be weighted and/or chosen.
#11l
11l
UInt32 seed = 0 F nonrandom(n)  :seed = 1664525 * :seed + 1013904223 R Int(:seed >> 16) % n F nonrandom_choice(lst) R lst[nonrandom(lst.len)]   F basecount(dna) DefaultDict[Char, Int] d L(c) dna d[c]++ R sorted(d.items())   F seq_split(dna, n = 50) R (0 .< dna.len).step(n).map(i -> @dna[i .< i + @n])   F seq_pp(dna, n = 50) L(part) seq_split(dna, n) print(‘#5: #.’.format(L.index * n, part)) print("\n BASECOUNT:") V tot = 0 L(base, count) basecount(dna) print(‘ #3: #.’.format(base, count)) tot += count V (base, count) = (‘TOT’, tot) print(‘ #3= #.’.format(base, count))   F seq_mutate(String =dna; count = 1, kinds = ‘IDSSSS’, choice = ‘ATCG’) [(String, Int)] mutation V k2txt = [‘I’ = ‘Insert’, ‘D’ = ‘Delete’, ‘S’ = ‘Substitute’] L 0 .< count V kind = nonrandom_choice(kinds) V index = nonrandom(dna.len + 1) I kind == ‘I’ dna = dna[0 .< index]‘’nonrandom_choice(choice)‘’dna[index..] E I kind == ‘D’ & !dna.empty dna = dna[0 .< index]‘’dna[index+1..] E I kind == ‘S’ & !dna.empty dna = dna[0 .< index]‘’nonrandom_choice(choice)‘’dna[index+1..] mutation.append((k2txt[kind], index)) R (dna, mutation)   print(‘SEQUENCE:’) V sequence = ‘TCAATCATTAATCGATTAATACATTCAATTTGAACATCTCCAGGAGAAGGCAGGGTAATCTCGTGTAGCCGTGCTTGGGGCCTCCGATATGGCCGGGGAATTTCAAAGTATAGTGTGCATCCCCTCATAATACATAGATCTATAGGTAAGTATATGGGTTGACGTTGTTAGATGCGATACACGTGCACACTTTATGAATTTTACGTTCCTCTGCCTAGAGTGCCAAGTTTCAATTTGCTACGGTTCCTCA’ seq_pp(sequence) print("\n\nMUTATIONS:") V (mseq, m) = seq_mutate(sequence, 10) L(kind, index) m print(‘ #10 @#.’.format(kind, index)) print() seq_pp(mseq)
http://rosettacode.org/wiki/Bitcoin/address_validation
Bitcoin/address validation
Bitcoin/address validation You are encouraged to solve this task according to the task description, using any language you may know. Task Write a program that takes a bitcoin address as argument, and checks whether or not this address is valid. A bitcoin address uses a base58 encoding, which uses an alphabet of the characters 0 .. 9, A ..Z, a .. z, but without the four characters:   0   zero   O   uppercase oh   I   uppercase eye   l   lowercase ell With this encoding, a bitcoin address encodes 25 bytes: the first byte is the version number, which will be zero for this task ; the next twenty bytes are a RIPEMD-160 digest, but you don't have to know that for this task: you can consider them a pure arbitrary data ; the last four bytes are a checksum check. They are the first four bytes of a double SHA-256 digest of the previous 21 bytes. To check the bitcoin address, you must read the first twenty-one bytes, compute the checksum, and check that it corresponds to the last four bytes. The program can either return a boolean value or throw an exception when not valid. You can use a digest library for SHA-256. Example of a bitcoin address 1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62i It doesn't belong to anyone and is part of the test suite of the bitcoin software. You can change a few characters in this string and check that it'll fail the test.
#D
D
import std.stdio, std.algorithm, std.array, std.string, sha_256_2;   struct A25 { // Type for a 25 ubyte (not base58 encoded) bitcoin address. ubyte[25] enc;   ubyte bitcoinVersion() const pure nothrow @safe @nogc { return enc[0]; }   ubyte[4] embeddedChecksum() return const pure nothrow @safe @nogc { return enc[$ - 4 .. $]; }   /** Computes a double sha256 hash of the first 21 bytes of the address. Returns the full 32 ubyte sha256 hash. */ ubyte[32] doubleSHA256() const pure nothrow @nogc { return SHA256.digest(SHA256.digest(enc[0 .. 21])); }   /** Returns a four ubyte checksum computed from the first 21 bytes of the address. */ ubyte[4] computeChecksum() const pure nothrow @nogc { return doubleSHA256[0 .. 4]; }   /** Takes a base58 encoded address and decodes it into the receiver. Errors are returned if the argument is not valid base58 or if the decoded value does not fit in the 25 ubyte address. The address is not otherwise checked for validity. */ string set58(in ubyte[] s) pure nothrow @safe @nogc { static immutable digits = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz" .representation; static assert(digits.length == 58);   foreach (immutable char s1; s) { immutable c = digits.countUntil(s1); if (c < 0) return "found a bad char in the Bitcoin address.";   // Currently the D type system can't see c as nonegative. uint uc = (c < 0) ? 0 : c;   foreach_reverse (ref aj; enc) { uc += digits.length * aj; aj = uc % 256; uc /= 256; } if (uc > 0) return "too long Bitcoin address."; }   return null; } }   /** Validates a base58 encoded bitcoin address. An address is valid if it can be decoded into a 25 ubyte address, the Version number is 0, and the checksum validates. Return value ok will be true for valid addresses. If ok is false, the address is invalid and the error value may indicate why. */ string isValidA58(in ubyte[] a58) pure nothrow @nogc { A25 a; immutable err = a.set58(a58); if (!err.empty) return err; if (a.bitcoinVersion != 0) return "not Bitcoin version 0."; return (a.embeddedChecksum == a.computeChecksum) ? null : "checksums don't match."; }   void main() { immutable tests = ["1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62i", "1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62j", "1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62!", "1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62iz", "1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62izz"];   foreach (immutable test; tests) { immutable err = test.representation.isValidA58; writefln(`"%s": %s`, test, err.empty ? "OK." : err); } }
http://rosettacode.org/wiki/Bitcoin/public_point_to_address
Bitcoin/public point to address
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion. The encoding steps are: take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed string ; add one byte prefix equal to 4 (it is a convention for this way of encoding a public point) ; compute the SHA-256 of this string ; compute the RIPEMD-160 of this SHA-256 digest ; compute the checksum of the concatenation of the version number digit (a single zero byte) and this RIPEMD-160 digest, as described in bitcoin/address validation ; Base-58 encode (see below) the concatenation of the version number (zero in this case), the ripemd digest and the checksum The base-58 encoding is based on an alphabet of alphanumeric characters (numbers, upper case and lower case, in that order) but without the four characters 0, O, l and I. Here is an example public point: X = 0x50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352 Y = 0x2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6 The corresponding address should be: 16UwLL9Risc3QfPqBUvKofHmBQ7wMtjvM Nb. The leading '1' is not significant as 1 is zero in base-58. It is however often added to the bitcoin address for various reasons. There can actually be several of them. You can ignore this and output an address without the leading 1. Extra credit: add a verification procedure about the public point, making sure it belongs to the secp256k1 elliptic curve
#Wolfram_Language.2FMathematica
Wolfram Language/Mathematica
BlockchainKeyEncode[ PublicKey[ <| "Type"->"EllipticCurve", "PublicCurvePoint"-> { 16^^50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352, 16^^2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6 } |> ], "Address", BlockchainBase-> "Bitcoin" ]
http://rosettacode.org/wiki/Bitcoin/public_point_to_address
Bitcoin/public point to address
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion. The encoding steps are: take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed string ; add one byte prefix equal to 4 (it is a convention for this way of encoding a public point) ; compute the SHA-256 of this string ; compute the RIPEMD-160 of this SHA-256 digest ; compute the checksum of the concatenation of the version number digit (a single zero byte) and this RIPEMD-160 digest, as described in bitcoin/address validation ; Base-58 encode (see below) the concatenation of the version number (zero in this case), the ripemd digest and the checksum The base-58 encoding is based on an alphabet of alphanumeric characters (numbers, upper case and lower case, in that order) but without the four characters 0, O, l and I. Here is an example public point: X = 0x50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352 Y = 0x2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6 The corresponding address should be: 16UwLL9Risc3QfPqBUvKofHmBQ7wMtjvM Nb. The leading '1' is not significant as 1 is zero in base-58. It is however often added to the bitcoin address for various reasons. There can actually be several of them. You can ignore this and output an address without the leading 1. Extra credit: add a verification procedure about the public point, making sure it belongs to the secp256k1 elliptic curve
#Nim
Nim
import parseutils import nimcrypto import bignum   func base58Encode(data: seq[byte]): string = ## Encode data to base58 with at most one starting '1'.   var data = data const Base = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz" result.setlen(34)   # Convert to base 58. for j in countdown(result.high, 0): var c = 0 for i, b in data: c = c * 256 + b.int data[i] = (c div 58).byte c = c mod 58 result[j] = Base[c]   # Keep one starting '1' at most. if result[0] == '1': for idx in 1..result.high: if result[idx] != '1': result = result[(idx - 1)..^1] break   func hexToByteSeq(s: string): seq[byte] = ## Convert a hexadecimal string to a sequence of bytes.   var pos = 0 while pos < s.len: var tmp = 0 let parsed = parseHex(s, tmp, pos, 2) if parsed > 0: inc pos, parsed result.add byte tmp else: raise newException(ValueError, "Invalid hex string")   func validCoordinates(x, y: string): bool = ## Return true if the coordinates are those of a point in the secp256k1 elliptic curve.   let p = newInt("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2F", 16) let x = newInt(x, 16) let y = newInt(y, 16) result = y^2 mod p == (x^3 + 7) mod p   func addrEncode(x, y: string): string = ## Encode x and y coordinates to an address.   if not validCoordinates(x, y): raise newException(ValueError, "Invalid coordinates")   let pubPoint = 4u8 & x.hexToByteSeq & y.hexToByteSeq if pubPoint.len != 65: raise newException(ValueError, "Invalid pubpoint string")   var rmd = @(ripemd160.digest(sha256.digest(pubPoint).data).data) rmd.insert 0u8 rmd.add sha256.digest(sha256.digest(rmd).data).data[0..3] result = base58Encode(rmd)   when isMainModule: let address = addrEncode("50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352", "2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6") echo "Coordinates are valid." echo "Address is: ", address
http://rosettacode.org/wiki/Bitcoin/public_point_to_address
Bitcoin/public point to address
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion. The encoding steps are: take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed string ; add one byte prefix equal to 4 (it is a convention for this way of encoding a public point) ; compute the SHA-256 of this string ; compute the RIPEMD-160 of this SHA-256 digest ; compute the checksum of the concatenation of the version number digit (a single zero byte) and this RIPEMD-160 digest, as described in bitcoin/address validation ; Base-58 encode (see below) the concatenation of the version number (zero in this case), the ripemd digest and the checksum The base-58 encoding is based on an alphabet of alphanumeric characters (numbers, upper case and lower case, in that order) but without the four characters 0, O, l and I. Here is an example public point: X = 0x50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352 Y = 0x2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6 The corresponding address should be: 16UwLL9Risc3QfPqBUvKofHmBQ7wMtjvM Nb. The leading '1' is not significant as 1 is zero in base-58. It is however often added to the bitcoin address for various reasons. There can actually be several of them. You can ignore this and output an address without the leading 1. Extra credit: add a verification procedure about the public point, making sure it belongs to the secp256k1 elliptic curve
#Perl
Perl
  use Crypt::RIPEMD160; use Digest::SHA qw(sha256); use Encode::Base58::GMP;   sub public_point_to_address { my $ec = join '', '04', @_; # EC: concat x and y to one string and prepend '04' magic value   my $octets = pack 'C*', map { hex } unpack('(a2)65', $ec); # transform the hex values string to octets my $hash = chr(0) . Crypt::RIPEMD160->hash(sha256 $octets); # perform RIPEMD160(SHA256(octets) my $checksum = substr sha256(sha256 $hash), 0, 4; # build the checksum my $hex = join '', '0x', # build hex value of hash and checksum map { sprintf "%02X", $_ } unpack 'C*', $hash.$checksum; return '1' . sprintf "%32s", encode_base58($hex, 'bitcoin'); # Do the Base58 encoding, prepend "1" }   say public_point_to_address '50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352', '2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6' ;  
http://rosettacode.org/wiki/Bitmap/Flood_fill
Bitmap/Flood fill
Implement a flood fill. A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point towards the banks (or: inside the valley): if there's a hole in the banks, the flood is not contained and all the image (or all the "connected valleys") get filled. To accomplish the task, you need to implement just one of the possible algorithms (examples are on Wikipedia). Variations on the theme are allowed (e.g. adding a tolerance parameter or argument for color-matching of the banks or target color). Testing: the basic algorithm is not suitable for truecolor images; a possible test image is the one shown on the right box; you can try to fill the white area, or the black inner circle.
#ERRE
ERRE
  PROGRAM MYFILL_DEMO   !VAR SP%   !$INTEGER   CONST IMAGE_WIDTH=320,IMAGE_HEIGHT=200   DIM STACK[6000,1]   FUNCTION QUEUE_COUNT(X) QUEUE_COUNT=SP END FUNCTION   !$INCLUDE="PC.LIB"   PROCEDURE QUEUE_INIT SP=0 END PROCEDURE   PROCEDURE QUEUE_POP(->XX,YY) XX=STACK[SP,0] YY=STACK[SP,1] SP=SP-1 END PROCEDURE   PROCEDURE QUEUE_PUSH(XX,YY) SP=SP+1 STACK[SP,0]=XX STACK[SP,1]=YY END PROCEDURE   PROCEDURE FLOOD_FILL(XSTART,YSTART,COLORE_PRIMA,COLORE_RIEMP) LOCAL XEST,XWEST,YNORD,YSUD,X,Y QUEUE_INIT QUEUE_PUSH(XSTART,YSTART) WHILE (QUEUE_COUNT(0)>0) DO QUEUE_POP(->X,Y) XWEST=X XEST=X   IF Y>0 THEN YNORD=Y-1 ELSE YNORD=-1 END IF   IF Y<IMAGE_HEIGHT-1 THEN YSUD=Y+1 ELSE YSUD=-1 END IF   LOOP POINT(XEST+1,Y->ZC%) EXIT IF NOT((XEST<IMAGE_WIDTH-1) AND (ZC%=COLORE_PRIMA)) XEST=XEST+1 END LOOP   LOOP POINT(XWEST-1,Y->ZC%) EXIT IF NOT((XWEST>0) AND (ZC%=COLORE_PRIMA)) XWEST=XWEST-1 END LOOP   FOR X=XWEST TO XEST DO PSET(X,Y,COLORE_RIEMP) POINT(X,YNORD->ZC%) IF YNORD>=0 AND ZC%=COLORE_PRIMA THEN QUEUE_PUSH(X,YNORD) END IF POINT(X,YSUD->ZC%) IF YSUD>=0 AND ZC%=COLORE_PRIMA THEN QUEUE_PUSH(X,YSUD) END IF END FOR END WHILE END PROCEDURE ! Flood_Fill   BEGIN SCREEN(1) CIRCLE(100,100,75,2) CIRCLE(120,120,20,2) CIRCLE(80,80,15,2) CIRCLE(120,80,10,2) FLOOD_FILL(100,100,0,1) END PROGRAM  
http://rosettacode.org/wiki/Bitmap/Flood_fill
Bitmap/Flood fill
Implement a flood fill. A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point towards the banks (or: inside the valley): if there's a hole in the banks, the flood is not contained and all the image (or all the "connected valleys") get filled. To accomplish the task, you need to implement just one of the possible algorithms (examples are on Wikipedia). Variations on the theme are allowed (e.g. adding a tolerance parameter or argument for color-matching of the banks or target color). Testing: the basic algorithm is not suitable for truecolor images; a possible test image is the one shown on the right box; you can try to fill the white area, or the black inner circle.
#Euler_Math_Toolbox
Euler Math Toolbox
  >file="test.png"; >A=loadrgb(file); ... >insrgb(A); >function floodfill (A0,i,j,color,dist) ... $ A=A0; $ R=getred(A); G=getgreen(A); B=getblue(A); $ d=sqrt((R-R[i,j])^2+(G-G[i,j])^2+(B-B[i,j])^2); $ n=rows(A); m=cols(A); $ V=zeros(n,m); $ S=zeros(n*m,2); sn=0; $ A[i,j]=color; V[i,j]=1; $ repeat; $ if fill(A,i+1,j,n,m,d,dist,V,S,sn,color) then i=i+1; continue; $ elseif fill(A,i,j+1,n,m,d,dist,V,S,sn,color) then j=j+1; continue; $ elseif fill(A,i-1,j,n,m,d,dist,V,S,sn,color) then i=i-1; continue; $ elseif fill(A,i,j-1,n,m,d,dist,V,S,sn,color) then j=j-1; continue; $ endif; $ sn=sn-1; if sn==0 then break; endif; $ i=S[sn,1]; j=S[sn,2]; $ end; $ return A; $endfunction >function fill (A,i,j,n,m,d,dist,V,S,%sn,color) ... $ if i<1 or i>n or j<1 or j>n then return 0; endif; $ if V[i,j] || d[i,j]>dist then A[i,j]=color; return 0; endif; $ V[i,j]=1; $ A[i,j]=color; $  %sn=%sn+1; $ S[%sn]=[i,j]; $ return 1; $endfunction >B=floodfill(A,10,240,rgb(0.5,0,0),0.5); >B=floodfill(B,10,10,rgb(0.5,0,0),0.5); >B=floodfill(B,150,60,rgb(0,0.5,0),0.5); >B=floodfill(B,200,200,rgb(0,0,0.5),0.5); >insrgb(B);  
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#Erlang
Erlang
1> 1 < 2. true 2> 1 < 1. false 3> 0 == false. false
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#Excel
Excel
=AND(A1;B1)
http://rosettacode.org/wiki/Caesar_cipher
Caesar cipher
Task Implement a Caesar cipher, both encoding and decoding. The key is an integer from 1 to 25. This cipher rotates (either towards left or right) the letters of the alphabet (A to Z). The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A). So key 2 encrypts "HI" to "JK", but key 20 encrypts "HI" to "BC". This simple "mono-alphabetic substitution cipher" provides almost no security, because an attacker who has the encoded message can either use frequency analysis to guess the key, or just try all 25 keys. Caesar cipher is identical to Vigenère cipher with a key of length 1. Also, Rot-13 is identical to Caesar cipher with key 13. Related tasks Rot-13 Substitution Cipher Vigenère Cipher/Cryptanalysis
#VBA
VBA
  Option Explicit   Sub Main_Caesar() Dim ch As String ch = Caesar_Cipher("CAESAR: Who is it in the press that calls on me? I hear a tongue, shriller than all the music, Cry 'Caesar!' Speak; Caesar is turn'd to hear.", 14) Debug.Print ch Debug.Print Caesar_Cipher(ch, -14) End Sub   Function Caesar_Cipher(sText As String, lngNumber As Long) As String Dim Tbl, strGlob As String, strTemp As String, i As Long, bytAscii As Byte Const MAJ As String = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" Const NB_LETTERS As Byte = 26 Const DIFFASCIIMAJ As Byte = 65 - NB_LETTERS Const DIFFASCIIMIN As Byte = 97 - NB_LETTERS   strTemp = sText If lngNumber < NB_LETTERS And lngNumber > NB_LETTERS * -1 Then strGlob = String(NB_LETTERS * 4, " ") LSet strGlob = MAJ & MAJ & MAJ Tbl = Split(StrConv(strGlob, vbUnicode), Chr(0)) For i = 1 To Len(strTemp) If Mid(strTemp, i, 1) Like "[a-zA-Z]" Then bytAscii = Asc(Mid(strTemp, i, 1)) If Mid(strTemp, i, 1) = Tbl(bytAscii - DIFFASCIIMAJ) Then Mid(strTemp, i) = Tbl(bytAscii - DIFFASCIIMAJ + lngNumber) Else Mid(strTemp, i) = LCase(Tbl(bytAscii - DIFFASCIIMIN + lngNumber)) End If End If Next i End If Caesar_Cipher = strTemp End Function  
http://rosettacode.org/wiki/Box_the_compass
Box the compass
There be many a land lubber that knows naught of the pirate ways and gives direction by degree! They know not how to box the compass! Task description Create a function that takes a heading in degrees and returns the correct 32-point compass heading. Use the function to print and display a table of Index, Compass point, and Degree; rather like the corresponding columns from, the first table of the wikipedia article, but use only the following 33 headings as input: [0.0, 16.87, 16.88, 33.75, 50.62, 50.63, 67.5, 84.37, 84.38, 101.25, 118.12, 118.13, 135.0, 151.87, 151.88, 168.75, 185.62, 185.63, 202.5, 219.37, 219.38, 236.25, 253.12, 253.13, 270.0, 286.87, 286.88, 303.75, 320.62, 320.63, 337.5, 354.37, 354.38]. (They should give the same order of points but are spread throughout the ranges of acceptance). Notes; The headings and indices can be calculated from this pseudocode: for i in 0..32 inclusive: heading = i * 11.25 case i %3: if 1: heading += 5.62; break if 2: heading -= 5.62; break end index = ( i mod 32) + 1 The column of indices can be thought of as an enumeration of the thirty two cardinal points (see talk page)..
#COBOL
COBOL
identification division. program-id. box-compass. data division. working-storage section. 01 point pic 99. 01 degrees usage float-short. 01 degrees-rounded pic 999v99. 01 show-degrees pic zz9.99. 01 box pic z9. 01 fudge pic 9. 01 compass pic x(4). 01 compass-point pic x(18). 01 shortform pic x. 01 short-names. 05 short-name pic x(4) occurs 33 times. 01 overlay. 05 value "N " & "NbE " & "N-NE" & "NEbN" & "NE " & "NEbE" & "E-NE" & "EbN " & "E " & "EbS " & "E-SE" & "SEbE" & "SE " & "SEbS" & "S-SE" & "SbE " & "S " & "SbW " & "S-SW" & "SWbS" & "SW " & "SWbW" & "W-SW" & "WbS " & "W " & "WbN " & "W-NW" & "NWbW" & "NW " & "NWbN" & "N-NW" & "NbW " & "N ".   procedure division. display "Index Compass point Degree"   move overlay to short-names. perform varying point from 0 by 1 until point > 32 compute box = function mod(point 32) + 1 compute degrees = point * 11.25 compute fudge = function mod(point 3) evaluate fudge when equal 1 add 5.62 to degrees when equal 2 subtract 5.62 from degrees end-evaluate   compute degrees-rounded rounded = degrees move degrees-rounded to show-degrees inspect show-degrees replacing trailing '00' by '0 ' inspect show-degrees replacing trailing '50' by '5 '   move short-name(point + 1) to compass move spaces to compass-point display space box space space space with no advancing perform varying tally from 1 by 1 until tally > 4 move compass(tally:1) to shortform move function concatenate(function trim(compass-point), function substitute(shortform, "N", "North", "E", "East", "S", "South", "W", "West", "b", " byZ", "-", "-")) to compass-point end-perform move function substitute(compass-point, "Z", " ") to compass-point move function lower-case(compass-point) to compass-point move function upper-case(compass-point(1:1)) to compass-point(1:1) display compass-point space show-degrees end-perform goback.
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, where N is the image width and M is the image height. Test task Histogram is useful for many image processing operations. As an example, use it to convert an image into black and white art. The method works as follows: Convert image to grayscale; Compute the histogram Find the median: defined as the luminance such that the image has an approximately equal number of pixels with lesser and greater luminance. Replace each pixel of luminance lesser than the median to black, and others to white. Use read/write ppm file, and grayscale image solutions.
#Scala
Scala
object BitmapOps { def histogram(bm:RgbBitmap)={ val hist=new Array[Int](255) for(x <- 0 until bm.width; y <- 0 until bm.height; l=luminosity(bm.getPixel(x,y))) hist(l)+=1 hist }   def histogram_median(hist:Array[Int])={ var from=0 var to=hist.size-1 var left=hist(from) var right=hist(to)   while(from!=to){ if (left<right) {from+=1; left+=hist(from)} else {to-=1; right+=hist(to)} } from }   def monochrom(bm:RgbBitmap, threshold:Int)={ val image=new RgbBitmap(bm.width, bm.height) val c1=Color.BLACK val c2=Color.WHITE for(x <- 0 until bm.width; y <- 0 until bm.height; l=luminosity(bm.getPixel(x,y))) image.setPixel(x, y, if(l>threshold) c2 else c1) image } }
http://rosettacode.org/wiki/Bitwise_operations
Bitwise operations
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation | Comparison | Matching Memory Operations Pointers & references | Addresses Task Write a routine to perform a bitwise AND, OR, and XOR on two integers, a bitwise NOT on the first integer, a left shift, right shift, right arithmetic shift, left rotate, and right rotate. All shifts and rotates should be done on the first integer with a shift/rotate amount of the second integer. If any operation is not available in your language, note it.
#Arturo
Arturo
a: 255 b: 2   print [a "AND" b "=" and a b] print [a "OR" b "=" or a b] print [a "XOR" b "=" xor a b] print ["NOT" a "=" not a] print [a "SHL" b "=" shl a b] print [a "SHR" b "=" shr a b]
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#Wren
Wren
import "graphics" for Canvas, ImageData, Color, Point import "dome" for Window   class Game { static bmpCreate(name, w, h) { ImageData.create(name, w, h) }   static bmpFill(name, col) { var image = ImageData[name] for (x in 0...image.width) { for (y in 0...image.height) image.pset(x, y, col) } }   static bmpPset(name, x, y, col) { ImageData[name].pset(x, y, col) }   static bmpPget(name, x, y) { ImageData[name].pget(x, y) }   static bmpLine(name, x0, y0, x1, y1, col) { var dx = (x1 - x0).abs var dy = (y1 - y0).abs var sx = (x0 < x1) ? 1 : -1 var sy = (y0 < y1) ? 1 : -1 var err = ((dx > dy ? dx : - dy) / 2).floor while (true) { bmpPset(name, x0, y0, col) if (x0 == x1 && y0 == y1) break var e2 = err if (e2 > -dx) { err = err - dy x0 = x0 + sx } if (e2 < dy) { err = err + dx y0 = y0 + sy } } }   static bmpQuadraticBezier(name, p1, p2, p3, col, n) { var pts = List.filled(n+1, null) for (i in 0..n) { var t = i / n var u = 1 - t var a = u * u var b = 2 * t * u var c = t * t var px = (a * p1.x + b * p2.x + c * p3.x).truncate var py = (a * p1.y + b * p2.y + c * p3.y).truncate pts[i] = Point.new(px, py, col) } for (i in 0...n) { var j = i + 1 bmpLine(name, pts[i].x, pts[i].y, pts[j].x, pts[j].y, col) } }   static init() { Window.title = "Quadratic Bézier curve" var size = 320 Window.resize(size, size) Canvas.resize(size, size) var name = "quadratic" var bmp = bmpCreate(name, size, size) bmpFill(name, Color.white) var p1 = Point.new( 10, 100) var p2 = Point.new(250, 270) var p3 = Point.new(150, 20) bmpQuadraticBezier(name, p1, p2, p3, Color.darkpurple, 20) bmp.draw(0, 0) }   static update() {}   static draw(alpha) {} }
http://rosettacode.org/wiki/Bitmap
Bitmap
Show a basic storage type to handle a simple RGB raster graphics image, and some primitive associated functions. If possible provide a function to allocate an uninitialised image, given its width and height, and provide 3 additional functions:   one to fill an image with a plain RGB color,   one to set a given pixel with a color,   one to get the color of a pixel. (If there are specificities about the storage or the allocation, explain those.) These functions are used as a base for the articles in the category raster graphics operations, and a basic output function to check the results is available in the article write ppm file.
#11l
11l
T Colour Byte r, g, b   F (r, g, b) .r = r .g = g .b = b   F ==(other) R .r == other.r & .g == other.g & .b == other.b   V black = Colour(0, 0, 0) V white = Colour(255, 255, 255)   T Bitmap Int width, height Colour background [[Colour]] map   F (width = 40, height = 40, background = white) assert(width > 0 & height > 0) .width = width .height = height .background = background .map = [[background] * width] * height   F fillrect(x, y, width, height, colour = black) assert(x >= 0 & y >= 0 & width > 0 & height > 0) L(h) 0 .< height L(w) 0 .< width .map[y + h][x + w] = colour   F chardisplay() V txt = .map.map(row -> row.map(bit -> (I bit == @@.background {‘ ’} E ‘@’)).join(‘’)) txt = txt.map(row -> ‘|’row‘|’) txt.insert(0, ‘+’(‘-’ * .width)‘+’) txt.append(‘+’(‘-’ * .width)‘+’) print(reversed(txt).join("\n"))   F set(x, y, colour = black) .map[y][x] = colour   F get(x, y) R .map[y][x]   V bitmap = Bitmap(20, 10) bitmap.fillrect(4, 5, 6, 3) assert(bitmap.get(5, 5) == black) assert(bitmap.get(0, 1) == white) bitmap.set(0, 1, black) assert(bitmap.get(0, 1) == black) bitmap.chardisplay()
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
SetAttributes[drawcircle, HoldFirst]; drawcircle[img_, {x0_, y0_}, r_, color_: White] := Module[{f = 1 - r, ddfx = 1, ddfy = -2 r, x = 0, y = r, pixels = {{0, r}, {0, -r}, {r, 0}, {-r, 0}}}, While[x < y, If[f >= 0, y--; ddfy += 2; f += ddfy]; x++; ddfx += 2; f += ddfx; pixels = Join[pixels, {{x, y}, {x, -y}, {-x, y}, {-x, -y}, {y, x}, {y, -x}, {-y, x}, {-y, -x}}]]; img = ReplacePixelValue[img, {x0, y0} + # -> color & /@ pixels]]
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#Modula-3
Modula-3
INTERFACE Circle;   IMPORT Bitmap;   PROCEDURE Draw( img: Bitmap.T; center: Bitmap.Point; radius: CARDINAL; color: Bitmap.Pixel);   END Circle.
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#J
J
require 'numeric'   bik=: 2 : '((*&(u!v))@(^&u * ^&(v-u)@-.))' basiscoeffs=: <: 4 : 'x bik y t. i.>:y'"0~ i. linearcomb=: basiscoeffs@#@[ evalBernstein=: ([ +/ .* linearcomb) p. ] NB. evaluate Bernstein Polynomial (general)   NB.*getBezierPoints v Returns points for bezier curve given control points (y) NB. eg: getBezierPoints controlpoints NB. y is: y0 x0, y1 x1, y2 x2 ... getBezierPoints=: monad define ctrlpts=. (/: {:"1) _2]\ y NB. sort ctrlpts for increasing x xvals=. ({: ,~ {. + +:@:i.@<.@-:@-~/) ({:"1) 0 _1{ctrlpts tvals=. ((] - {.) % ({: - {.)) xvals xvals ,.~ ({."1 ctrlpts) evalBernstein tvals )   NB.*drawBezier v Draws bezier curve defined by (x) on image (y) NB. eg: (42 40 10 30 186 269 26 187;255 0 0) drawBezier myimg NB. x is: 2-item list of boxed (controlpoints) ; (color) drawBezier=: (1&{:: ;~ 2 ]\ [: roundint@getBezierPoints"1 (0&{::))@[ drawLines ]
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#JavaScript
JavaScript
  function draw() { var canvas = document.getElementById("container"); context = canvas.getContext("2d");   bezier3(20, 200, 700, 50, -300, 50, 380, 150); // bezier3(160, 10, 10, 40, 30, 160, 150, 110); // bezier3(0,149, 30,50, 120,130, 160,30, 0); }   // http://rosettacode.org/wiki/Cubic_bezier_curves#C function bezier3(x1, y1, x2, y2, x3, y3, x4, y4) { var px = [], py = []; for (var i = 0; i <= b3Seg; i++) { var d = i / b3Seg; var a = 1 - d; var b = a * a; var c = d * d; a = a * b; b = 3 * b * d; c = 3 * a * c; d = c * d; px[i] = parseInt(a * x1 + b * x2 + c * x3 + d * x4); py[i] = parseInt(a * y1 + b * y2 + c * y3 + d * y4); } var x0 = px[0]; var y0 = py[0]; for (i = 1; i <= b3Seg; i++) { var x = px[i]; var y = py[i]; drawPolygon(context, [[x0, y0], [x, y]], "red", "red"); x0 = x; y0 = y; } } function drawPolygon(context, polygon, strokeStyle, fillStyle) { context.strokeStyle = strokeStyle; context.beginPath();   context.moveTo(polygon[0][0],polygon[0][1]); for (i = 1; i < polygon.length; i++) context.lineTo(polygon[i][0],polygon[i][1]);   context.closePath(); context.stroke();   if (fillStyle == undefined) return; context.fillStyle = fillStyle; context.fill(); }  
http://rosettacode.org/wiki/Biorhythms
Biorhythms
For a while in the late 70s, the pseudoscience of biorhythms was popular enough to rival astrology, with kiosks in malls that would give you your weekly printout. It was also a popular entry in "Things to Do with your Pocket Calculator" lists. You can read up on the history at Wikipedia, but the main takeaway is that unlike astrology, the math behind biorhythms is dead simple. It's based on the number of days since your birth. The premise is that three cycles of unspecified provenance govern certain aspects of everyone's lives – specifically, how they're feeling physically, emotionally, and mentally. The best part is that not only do these cycles somehow have the same respective lengths for all humans of any age, gender, weight, genetic background, etc, but those lengths are an exact number of days. And the pattern is in each case a perfect sine curve. Absolutely miraculous! To compute your biorhythmic profile for a given day, the first thing you need is the number of days between that day and your birth, so the answers in Days between dates are probably a good starting point. (Strictly speaking, the biorhythms start at 0 at the moment of your birth, so if you know time of day you can narrow things down further, but in general these operate at whole-day granularity.) Then take the residue of that day count modulo each of the the cycle lengths to calculate where the day falls on each of the three sinusoidal journeys. The three cycles and their lengths are as follows: Cycle Length Physical 23 days Emotional 28 days Mental 33 days The first half of each cycle is in "plus" territory, with a peak at the quarter-way point; the second half in "minus" territory, with a valley at the three-quarters mark. You can calculate a specific value between -1 and +1 for the kth day of an n-day cycle by computing sin( 2πk / n ). The days where a cycle crosses the axis in either direction are called "critical" days, although with a cycle value of 0 they're also said to be the most neutral, which seems contradictory. The task: write a subroutine, function, or program that will, given a birthdate and a target date, output the three biorhythmic values for the day. You may optionally include a text description of the position and the trend (e.g. "up and rising", "peak", "up but falling", "critical", "down and falling", "valley", "down but rising"), an indication of the date on which the next notable event (peak, valley, or crossing) falls, or even a graph of the cycles around the target date. Demonstrate the functionality for dates of your choice. Example run of my Raku implementation: raku br.raku 1943-03-09 1972-07-11 Output: Day 10717: Physical day 22: -27% (down but rising, next transition 1972-07-12) Emotional day 21: valley Mental day 25: valley Double valley! This was apparently not a good day for Mr. Fischer to begin a chess tournament...
#Common_Lisp
Common Lisp
;;;; Common Lisp biorhythms   ;;; Get the days to J2000 ;;; FNday only works between 1901 to 2099 - see Meeus chapter 7   (defun day (y m d) (+ (truncate (* -7 (+ y (truncate (+ m 9) 12))) 4) (truncate (* 275 m) 9) d -730530 (* 367 y)))   ;;; Get the difference in days between two dates   (defun diffday (y1 m1 d1 y2 m2 d2) (abs (- (day y2 m2 d2) (day y1 m1 d1))))   ;;; Print state of a single cycle   (defun print-cycle (diff len nm) (let ((perc (round (* 100 (sin (* 2 pi diff (/ 1 len))))))) (format t "~A cycle: ~D% " nm perc) (if (< (abs perc) 15) (format t "(critical)~%") (format t "~%"))))   ;;; Print all cycles   (defun print-bio (y1 m1 d1 y2 m2 d2) (let ((diff (diffday y1 m1 d1 y2 m2 d2))) (format t "Age in days: ~D ~%" diff) (print-cycle diff 23 "physical") (print-cycle diff 28 "emotional") (print-cycle diff 33 "intellectual")))
http://rosettacode.org/wiki/Biorhythms
Biorhythms
For a while in the late 70s, the pseudoscience of biorhythms was popular enough to rival astrology, with kiosks in malls that would give you your weekly printout. It was also a popular entry in "Things to Do with your Pocket Calculator" lists. You can read up on the history at Wikipedia, but the main takeaway is that unlike astrology, the math behind biorhythms is dead simple. It's based on the number of days since your birth. The premise is that three cycles of unspecified provenance govern certain aspects of everyone's lives – specifically, how they're feeling physically, emotionally, and mentally. The best part is that not only do these cycles somehow have the same respective lengths for all humans of any age, gender, weight, genetic background, etc, but those lengths are an exact number of days. And the pattern is in each case a perfect sine curve. Absolutely miraculous! To compute your biorhythmic profile for a given day, the first thing you need is the number of days between that day and your birth, so the answers in Days between dates are probably a good starting point. (Strictly speaking, the biorhythms start at 0 at the moment of your birth, so if you know time of day you can narrow things down further, but in general these operate at whole-day granularity.) Then take the residue of that day count modulo each of the the cycle lengths to calculate where the day falls on each of the three sinusoidal journeys. The three cycles and their lengths are as follows: Cycle Length Physical 23 days Emotional 28 days Mental 33 days The first half of each cycle is in "plus" territory, with a peak at the quarter-way point; the second half in "minus" territory, with a valley at the three-quarters mark. You can calculate a specific value between -1 and +1 for the kth day of an n-day cycle by computing sin( 2πk / n ). The days where a cycle crosses the axis in either direction are called "critical" days, although with a cycle value of 0 they're also said to be the most neutral, which seems contradictory. The task: write a subroutine, function, or program that will, given a birthdate and a target date, output the three biorhythmic values for the day. You may optionally include a text description of the position and the trend (e.g. "up and rising", "peak", "up but falling", "critical", "down and falling", "valley", "down but rising"), an indication of the date on which the next notable event (peak, valley, or crossing) falls, or even a graph of the cycles around the target date. Demonstrate the functionality for dates of your choice. Example run of my Raku implementation: raku br.raku 1943-03-09 1972-07-11 Output: Day 10717: Physical day 22: -27% (down but rising, next transition 1972-07-12) Emotional day 21: valley Mental day 25: valley Double valley! This was apparently not a good day for Mr. Fischer to begin a chess tournament...
#Delphi
Delphi
  program Biorhythms;   {$APPTYPE CONSOLE}   uses System.SysUtils, System.Math;   var cycles: array[0..2] of string = ('Physical day ', 'Emotional day', 'Mental day '); lengths: array[0..2] of Integer = (23, 28, 33); quadrants: array[0..3] of array[0..1] of string = (('up and rising', 'peak'), ('up but falling', 'transition'), ('down and falling', 'valley'), ('down but rising', 'transition')); datePairs: array[0..2] of array[0..1] of string = (('1943-03-09', '1972-07-11'), ('1809-01-12', '1863-11-19'), ('1809-02-12', '1863-11-19') // correct DOB for Abraham Lincoln );   procedure Check(err: string); begin if not err.IsEmpty then raise Exception.Create(err); end;   function ParseDate(sDate: string; var Date: TDateTime): string; var dtFormat: TFormatSettings; begin Result := ''; with dtFormat do begin DateSeparator := '-'; ShortDateFormat := 'yyyy-mm-dd'; end;   try Date := StrtoDateTime(sDate, dtFormat); except on E: Exception do Result := E.Message; end; end;   function DateToStr(dt: TDateTime): string; var dtFormat: TFormatSettings; begin Result := ''; with dtFormat do begin DateSeparator := '-'; ShortDateFormat := 'yyyy-mm-dd'; end; Result := DateTimeToStr(dt, dtFormat); end;   // Parameters assumed to be in YYYY-MM-DD format. procedure CalcBiorhythms(birthDate, targetDate: string); var bd, td: TDateTime; days: Integer; begin Check(ParseDate(birthDate, bd)); Check(ParseDate(targetDate, td)); days := Trunc(td - bd); writeln('Born ', birthDate, ', Target ', targetDate); Writeln('Days ', days); for var i := 0 to 2 do begin var len := lengths[i]; var cycle := cycles[i]; var position := days mod len; var quadrant: Integer := trunc(position * 4 / len); var percent := sin(2.0 * PI * position / len);   percent := floor(percent * 1000) / 10; var descript := ''; if percent > 95 then descript := ' peak' else if percent < -95 then descript := ' valley' else if abs(percent) < 5 then descript := ' critical transition' else begin var daysToAdd := trunc((quadrant + 1) * len / 4 - position); var transition := td + daysToAdd; var trend := quadrants[quadrant, 0]; var next := quadrants[quadrant, 1]; var transStr := DateToStr(transition); var percentRounded := percent; descript := format('%5.3f%% (%s, next %s %s)', [percentRounded, trend, next, transStr]); end; writeln(format('%s %2d : %s', [cycle, position, descript])); end; writeln; end;   begin for var i := 0 to High(datePairs) do CalcBiorhythms(datePairs[i, 0], datePairs[i, 1]); readln; end.
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#XPL0
XPL0
include c:\cxpl\codes; \intrinsic 'code' declarations def Width=180, Height=135, Color=$123456;   proc WriteImage; \Write screen image to a a PPM file int X, Y, C; [Text(3,"P6 "); IntOut(3,Width); ChOut(3,^ ); IntOut(3,Height); Text(3," 255 "); for Y:= 0 to Height-1 do for X:= 0 to Width-1 do [C:= ReadPix(X, Y); ChOut(3, C>>16); ChOut(3, C>>8); ChOut(3, C); ]; ];   proc OpenOutFile(FN); \Open for output the named file char FN; \file name string int H; \handle [H:= FOpen(FN, 1); FSet(H, ^o); \small buffer allows multiple files, and it is OpenO(3); \ closed automatically when the program exits ];   proc MakeImage; \Make a bitmap image int X, Y; [for Y:= 0 to Height-1 do \fill area with Color for X:= 0 to Width-1 do Point(X, Y, Color); Move(60, 60); HexOut(6, ReadPix(0,0)); \show hex value of color of pixel at 0,0 ];   [SetVid($112); \set display for 640x480 graphics in 24-bit RGB color MakeImage; OpenOutFile("IMAGE.PPM"); WriteImage; SetVid(3); \restore display to normal text mode ]
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#Yabasic
Yabasic
clear screen   wid = 150 : hei = 200 open window wid, hei window origin "cc" color 255, 0, 0 fill circle 0, 0, 50 color 0, 255, 0 fill circle 0, 0, 35 color 0, 0, 255 fill circle 0, 0, 20 window origin "lt"   header$ = "P6\n" + str$(wid) + " " + str$(hei) + "\n255\n"   fn = open("exmaple.PPM", "wb")   print #fn header$   for x = 0 to hei - 1 for y = 0 to wid - 1 c$ = right$(getbit$(y, x, y, x), 6) poke #fn, dec(left$(c$, 2)) poke #fn, dec(right$(c$, 2)) poke #fn, dec(mid$(c$, 3, 2)) next y next x   poke #fn, asc("\n") close #fn
http://rosettacode.org/wiki/Bitmap/Bresenham%27s_line_algorithm
Bitmap/Bresenham's line algorithm
Task Using the data storage type defined on the Bitmap page for raster graphics images, draw a line given two points with Bresenham's line algorithm.
#Assembly
Assembly
.486 IDEAL ;--------------------------------------------- ; case: DeltaY is bigger than DeltaX ; input: p1X p1Y, ; p2X p2Y, ; Color -> variable ; output: line on the screen ;--------------------------------------------- Macro DrawLine2DDY p1X, p1Y, p2X, p2Y local l1, lp, nxt mov dx, 1 mov ax, [p1X] cmp ax, [p2X] jbe l1 neg dx ; turn delta to -1 l1: mov ax, [p2Y] shr ax, 1 ; div by 2 mov [TempW], ax mov ax, [p1X] mov [pointX], ax mov ax, [p1Y] mov [pointY], ax mov bx, [p2Y] sub bx, [p1Y] absolute bx mov cx, [p2X] sub cx, [p1X] absolute cx mov ax, [p2Y] lp: pusha call PIXEL popa inc [pointY] cmp [TempW], 0 jge nxt add [TempW], bx ; bx = (p2Y - p1Y) = deltay add [pointX], dx ; dx = delta nxt: sub [TempW], cx ; cx = abs(p2X - p1X) = daltax cmp [pointY], ax ; ax = p2Y jne lp call PIXEL ENDM DrawLine2DDY ;--------------------------------------------- ; case: DeltaX is bigger than DeltaY ; input: p1X p1Y, ; p2X p2Y, ; Color -> variable ; output: line on the screen ;--------------------------------------------- Macro DrawLine2DDX p1X, p1Y, p2X, p2Y local l1, lp, nxt mov dx, 1 mov ax, [p1Y] cmp ax, [p2Y] jbe l1 neg dx ; turn delta to -1 l1: mov ax, [p2X] shr ax, 1 ; div by 2 mov [TempW], ax mov ax, [p1X] mov [pointX], ax mov ax, [p1Y] mov [pointY], ax mov bx, [p2X] sub bx, [p1X] absolute bx mov cx, [p2Y] sub cx, [p1Y] absolute cx mov ax, [p2X] lp: pusha call PIXEL popa inc [pointX] cmp [TempW], 0 jge nxt add [TempW], bx ; bx = abs(p2X - p1X) = deltax add [pointY], dx ; dx = delta nxt: sub [TempW], cx ; cx = abs(p2Y - p1Y) = deltay cmp [pointX], ax ; ax = p2X jne lp call PIXEL ENDM DrawLine2DDX Macro absolute a local l1 cmp a, 0 jge l1 neg a l1: Endm MODEL small STACK 256 DATASEG TempW dw ? pointX dw ? pointY dw ? point1X dw ? point1Y dw ? point2X dw ? point2Y dw ? Color db ? CODESEG start: mov ax, @data mov ds, ax mov ax, 13h int 10h ; set graphic mode mov [Color], 61 mov [point1X], 300 mov [point2X], 6 mov [point1Y], 122 mov [point2Y], 88 call DrawLine2D mov ah, 00h int 16h exit: mov ax,03h int 10h ; set text mode mov ax, 4C00h int 21h ; procedures ;--------------------------------------------- ; input: point1X point1Y, ; point2X point2Y, ; Color ; output: line on the screen ;--------------------------------------------- PROC DrawLine2D mov cx, [point1X] sub cx, [point2X] absolute cx mov bx, [point1Y] sub bx, [point2Y] absolute bx cmp cx, bx jae DrawLine2Dp1 ; deltaX > deltaY mov ax, [point1X] mov bx, [point2X] mov cx, [point1Y] mov dx, [point2Y] cmp cx, dx jbe DrawLine2DpNxt1 ; point1Y <= point2Y xchg ax, bx xchg cx, dx DrawLine2DpNxt1: mov [point1X], ax mov [point2X], bx mov [point1Y], cx mov [point2Y], dx DrawLine2DDY point1X, point1Y, point2X, point2Y ret DrawLine2Dp1: mov ax, [point1X] mov bx, [point2X] mov cx, [point1Y] mov dx, [point2Y] cmp ax, bx jbe DrawLine2DpNxt2 ; point1X <= point2X xchg ax, bx xchg cx, dx DrawLine2DpNxt2: mov [point1X], ax mov [point2X], bx mov [point1Y], cx mov [point2Y], dx DrawLine2DDX point1X, point1Y, point2X, point2Y ret ENDP DrawLine2D ;----------------------------------------------- ; input: pointX pointY, ; Color ; output: point on the screen ;----------------------------------------------- PROC PIXEL mov bh,0h mov cx,[pointX] mov dx,[pointY] mov al,[Color] mov ah,0Ch int 10h ret ENDP PIXEL END start
http://rosettacode.org/wiki/Bioinformatics/Sequence_mutation
Bioinformatics/Sequence mutation
Task Given a string of characters A, C, G, and T representing a DNA sequence write a routine to mutate the sequence, (string) by: Choosing a random base position in the sequence. Mutate the sequence by doing one of either: Swap the base at that position by changing it to one of A, C, G, or T. (which has a chance of swapping the base for the same base) Delete the chosen base at the position. Insert another base randomly chosen from A,C, G, or T into the sequence at that position. Randomly generate a test DNA sequence of at least 200 bases "Pretty print" the sequence and a count of its size, and the count of each base in the sequence Mutate the sequence ten times. "Pretty print" the sequence after all mutations, and a count of its size, and the count of each base in the sequence. Extra credit Give more information on the individual mutations applied. Allow mutations to be weighted and/or chosen.
#Ada
Ada
with Ada.Containers.Vectors; with Ada.Numerics.Discrete_Random; with Ada.Text_Io;   procedure Mutations is   Width : constant := 60;   type Nucleotide_Type is (A, C, G, T); type Operation_Type is (Delete, Insert, Swap); type Position_Type is new Natural;   package Position_Io is new Ada.Text_Io.Integer_Io (Position_Type); package Nucleotide_Io is new Ada.Text_Io.Enumeration_Io (Nucleotide_Type); package Operation_Io is new Ada.Text_Io.Enumeration_Io (Operation_Type);   use Ada.Text_Io, Position_Io, Nucleotide_Io, Operation_Io;   package Sequence_Vectors is new Ada.Containers.Vectors (Index_Type => Position_Type, Element_Type => Nucleotide_Type); package Nucleotide_Generators is new Ada.Numerics.Discrete_Random (Result_Subtype => Nucleotide_Type); package Operation_Generators is new Ada.Numerics.Discrete_Random (Result_Subtype => Operation_Type);   procedure Pretty_Print (Sequence : Sequence_Vectors.Vector) is First : Position_Type := Sequence.First_Index; Last  : Position_Type; Count : array (Nucleotide_Type) of Natural := (others => 0); begin Last := Position_Type'Min (First + Width - 1, Sequence.Last_Index); loop Position_Io.Put (First, Width => 4); Put (": "); for N in First .. Last loop declare Nucleotide : Nucleotide_Type renames Sequence (N); begin Put (Nucleotide); Count (Nucleotide) := Count (Nucleotide) + 1; end; end loop; New_Line; exit when Last = Sequence.Last_Index; First := Last + 1; Last  := Position_Type'Min (First + Width - 1, Sequence.Last_Index); end loop;   for N in Count'Range loop Put ("Count of "); Put (N); Put (" is "); Put (Natural'Image (Count (N))); New_Line; end loop;   end Pretty_Print;   function Random_Position (First, Last : Position_Type) return Position_Type is subtype Position_Range is Position_Type range First .. Last; package Position_Generators is new Ada.Numerics.Discrete_Random (Result_Subtype => Position_Range); Generator : Position_Generators.Generator; begin Position_Generators.Reset (Generator); return Position_Generators.Random (Generator); end Random_Position;   Nucleotide_Generator : Nucleotide_Generators.Generator; Operation_Generator  : Operation_Generators.Generator;   Sequence  : Sequence_Vectors.Vector; Position  : Position_Type; Nucleotide : Nucleotide_Type; Operation  : Operation_Type; begin Nucleotide_Generators.Reset (Nucleotide_Generator); Operation_Generators.Reset (Operation_Generator);   for A in 1 .. 200 loop Sequence.Append (Nucleotide_Generators.Random (Nucleotide_Generator)); end loop;   Put_Line ("Initial sequence:"); Pretty_Print (Sequence); New_Line;   Put_Line ("Mutations:"); for Mutate in 1 .. 10 loop   Operation := Operation_Generators.Random (Operation_Generator); case Operation is   when Delete => Position := Random_Position (Sequence.First_Index, Sequence.Last_Index); Sequence.Delete (Index => Position); Put (Operation); Put (" at position "); Put (Position, Width => 0); New_Line;   when Insert => Position  := Random_Position (Sequence.First_Index, Sequence.Last_Index + 1); Nucleotide := Nucleotide_Generators.Random (Nucleotide_Generator); Sequence.Insert (Before => Position, New_Item => Nucleotide); Put (Operation); Put (" "); Put (Nucleotide); Put (" at position "); Put (Position, Width => 0); New_Line;   when Swap => Position  := Random_Position (Sequence.First_Index, Sequence.Last_Index); Nucleotide := Nucleotide_Generators.Random (Nucleotide_Generator); Sequence.Replace_Element (Index => Position, New_Item => Nucleotide); Put (Operation); Put (" at position "); Put (Position, Width => 0); Put (" to "); Put (Nucleotide); New_Line;   end case; end loop;   New_Line; Put_Line ("Mutated sequence:"); Pretty_Print (Sequence);   end Mutations;
http://rosettacode.org/wiki/Bitcoin/address_validation
Bitcoin/address validation
Bitcoin/address validation You are encouraged to solve this task according to the task description, using any language you may know. Task Write a program that takes a bitcoin address as argument, and checks whether or not this address is valid. A bitcoin address uses a base58 encoding, which uses an alphabet of the characters 0 .. 9, A ..Z, a .. z, but without the four characters:   0   zero   O   uppercase oh   I   uppercase eye   l   lowercase ell With this encoding, a bitcoin address encodes 25 bytes: the first byte is the version number, which will be zero for this task ; the next twenty bytes are a RIPEMD-160 digest, but you don't have to know that for this task: you can consider them a pure arbitrary data ; the last four bytes are a checksum check. They are the first four bytes of a double SHA-256 digest of the previous 21 bytes. To check the bitcoin address, you must read the first twenty-one bytes, compute the checksum, and check that it corresponds to the last four bytes. The program can either return a boolean value or throw an exception when not valid. You can use a digest library for SHA-256. Example of a bitcoin address 1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62i It doesn't belong to anyone and is part of the test suite of the bitcoin software. You can change a few characters in this string and check that it'll fail the test.
#Dart
Dart
import 'package:crypto/crypto.dart';   class Bitcoin { final String ALPHABET = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";   List<int> bigIntToByteArray(BigInt data) { String str; bool neg = false; if (data < BigInt.zero) { str = (~data).toRadixString(16); neg = true; } else str = data.toRadixString(16); int p = 0; int len = str.length;   int blen = (len + 1) ~/ 2; int boff = 0; List bytes; if (neg) { if (len & 1 == 1) { p = -1; } int byte0 = ~int.parse(str.substring(0, p + 2), radix: 16); if (byte0 < -128) byte0 += 256; if (byte0 >= 0) { boff = 1; bytes = new List<int>(blen + 1); bytes[0] = -1; bytes[1] = byte0; } else { bytes = new List<int>(blen); bytes[0] = byte0; } for (int i = 1; i < blen; ++i) { int byte = ~int.parse(str.substring(p + (i << 1), p + (i << 1) + 2), radix: 16); if (byte < -128) byte += 256; bytes[i + boff] = byte; } } else { if (len & 1 == 1) { p = -1; } int byte0 = int.parse(str.substring(0, p + 2), radix: 16); if (byte0 > 127) byte0 -= 256; if (byte0 < 0) { boff = 1; bytes = new List<int>(blen + 1); bytes[0] = 0; bytes[1] = byte0; } else { bytes = new List<int>(blen); bytes[0] = byte0; } for (int i = 1; i < blen; ++i) { int byte = int.parse(str.substring(p + (i << 1), p + (i << 1) + 2), radix: 16); if (byte > 127) byte -= 256; bytes[i + boff] = byte; } } return bytes; }   List<int> arrayCopy(bytes, srcOffset, result, destOffset, bytesLength) { for (int i = srcOffset; i < bytesLength; i++) { result[destOffset + i] = bytes[i]; } return result; }   List<int> decodeBase58To25Bytes(String input) { BigInt number = BigInt.zero; for (String t in input.split('')) { int p = ALPHABET.indexOf(t); if (p == (-1)) return null; number = number * (BigInt.from(58)) + (BigInt.from(p)); } List<int> result = new List<int>(24); List<int> numBytes = bigIntToByteArray(number); return arrayCopy( numBytes, 0, result, result.length - numBytes.length, numBytes.length); }   validateAddress(String address) { List<int> decoded = new List.from(decodeBase58To25Bytes(address)); List<int> temp = new List<int>.from(decoded); temp.insert(0, 0); List<int> hash1 = sha256.convert(temp.sublist(0, 21)).bytes; List<int> hash2 = sha256.convert(hash1).bytes; if (hash2[0] != decoded[20] || hash2[1] != decoded[21] || hash2[2] != decoded[22] || hash2[3] != decoded[23]) return false; return true; } }
http://rosettacode.org/wiki/Bitcoin/address_validation
Bitcoin/address validation
Bitcoin/address validation You are encouraged to solve this task according to the task description, using any language you may know. Task Write a program that takes a bitcoin address as argument, and checks whether or not this address is valid. A bitcoin address uses a base58 encoding, which uses an alphabet of the characters 0 .. 9, A ..Z, a .. z, but without the four characters:   0   zero   O   uppercase oh   I   uppercase eye   l   lowercase ell With this encoding, a bitcoin address encodes 25 bytes: the first byte is the version number, which will be zero for this task ; the next twenty bytes are a RIPEMD-160 digest, but you don't have to know that for this task: you can consider them a pure arbitrary data ; the last four bytes are a checksum check. They are the first four bytes of a double SHA-256 digest of the previous 21 bytes. To check the bitcoin address, you must read the first twenty-one bytes, compute the checksum, and check that it corresponds to the last four bytes. The program can either return a boolean value or throw an exception when not valid. You can use a digest library for SHA-256. Example of a bitcoin address 1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62i It doesn't belong to anyone and is part of the test suite of the bitcoin software. You can change a few characters in this string and check that it'll fail the test.
#Delphi
Delphi
  uses DCPsha256;   type TByteArray = array of Byte;   function HashSHA256(const Input: TByteArray): TByteArray; var Hasher: TDCP_sha256; begin Hasher := TDCP_sha256.Create(nil); try Hasher.Init; Hasher.Update(Input[0], Length(Input)); SetLength(Result, Hasher.HashSize div 8); Hasher.Final(Result[0]); finally Hasher.Free; end; end;   function DecodeBase58(const Input: string): TByteArray; const Size = 25; Alphabet = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'; var C: Char; I, J: Integer; begin SetLength(Result, Size);   for C in Input do begin I := Pos(C, Alphabet) - 1;   if I = -1 then raise Exception.CreateFmt('Invalid character found: %s', [C]);   for J := High(Result) downto 0 do begin I := I + (58 * Result[J]); Result[J] := I mod 256; I := I div 256; end;   if I <> 0 then raise Exception.Create('Address too long'); end; end;   procedure ValidateBitcoinAddress(const Address: string); var Hashed: TByteArray; Decoded: TByteArray; begin if (Length(Address) < 26) or (Length(Address) > 35) then raise Exception.Create('Wrong length');   Decoded := DecodeBase58(Address); Hashed := HashSHA256(HashSHA256(Copy(Decoded, 0, 21)));   if not CompareMem(@Decoded[21], @Hashed[0], 4) then raise Exception.Create('Bad digest'); end;  
http://rosettacode.org/wiki/Bitcoin/public_point_to_address
Bitcoin/public point to address
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion. The encoding steps are: take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed string ; add one byte prefix equal to 4 (it is a convention for this way of encoding a public point) ; compute the SHA-256 of this string ; compute the RIPEMD-160 of this SHA-256 digest ; compute the checksum of the concatenation of the version number digit (a single zero byte) and this RIPEMD-160 digest, as described in bitcoin/address validation ; Base-58 encode (see below) the concatenation of the version number (zero in this case), the ripemd digest and the checksum The base-58 encoding is based on an alphabet of alphanumeric characters (numbers, upper case and lower case, in that order) but without the four characters 0, O, l and I. Here is an example public point: X = 0x50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352 Y = 0x2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6 The corresponding address should be: 16UwLL9Risc3QfPqBUvKofHmBQ7wMtjvM Nb. The leading '1' is not significant as 1 is zero in base-58. It is however often added to the bitcoin address for various reasons. There can actually be several of them. You can ignore this and output an address without the leading 1. Extra credit: add a verification procedure about the public point, making sure it belongs to the secp256k1 elliptic curve
#Phix
Phix
without javascript_semantics -- no ripemd160.js as yet include builtins\sha256.e include builtins\ripemd160.e constant b58 = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz" function base58(string s) string out = "" if length(s)!=25 then ?9/0 end if for n=1 to 34 do integer c = 0 for i=1 to 25 do c = c*256+s[i] s[i] = floor(c/58) c = mod(c,58) end for out &= b58[c+1] end for if out[$]='1' then for i=length(out)-1 to 1 by -1 do if out[i]!='1' then out = out[1..i+1] exit end if end for end if return reverse(out) end function function coin_encode(string x, y) if length(x)!=32 or length(y)!=32 then return "bad public point string" end if string s = "\x04" & x & y string rmd = '\0'&ripemd160(sha256(s),false) rmd &= sha256(sha256(rmd))[1..4] string res = base58(rmd) return res end function ?coin_encode(x"50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352", x"2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6")
http://rosettacode.org/wiki/Bitmap/Flood_fill
Bitmap/Flood fill
Implement a flood fill. A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point towards the banks (or: inside the valley): if there's a hole in the banks, the flood is not contained and all the image (or all the "connected valleys") get filled. To accomplish the task, you need to implement just one of the possible algorithms (examples are on Wikipedia). Variations on the theme are allowed (e.g. adding a tolerance parameter or argument for color-matching of the banks or target color). Testing: the basic algorithm is not suitable for truecolor images; a possible test image is the one shown on the right box; you can try to fill the white area, or the black inner circle.
#FBSL
FBSL
#DEFINE WM_LBUTTONDOWN 513 #DEFINE WM_CLOSE 16   FBSLSETTEXT(ME, "Before Flood Fill") ' Set form caption FBSLSETFORMCOLOR(ME, RGB(0, 255, 255)) ' Cyan: persistent background color FBSL.GETDC(ME) ' Use volatile FBSL.GETDC below to avoid extra assignments   RESIZE(ME, 0, 0, 220, 220) CENTER(ME) SHOW(ME)   DIM Breadth AS INTEGER, Height AS INTEGER FBSL.GETCLIENTRECT(ME, 0, 0, Breadth, Height)   DrawCircles() ' Initialize circles   BEGIN EVENTS SELECT CASE CBMSG CASE WM_LBUTTONDOWN: FillCircles() ' Flood fill circles CASE WM_CLOSE: FBSL.RELEASEDC(ME, FBSL.GETDC) ' Clean up END SELECT END EVENTS   SUB FillCircles() FILL(FBSL.GETDC, Breadth / 2, Height / 2, &HFFFF) ' Yellow: flood fill using intrinsics FOR DIM x = 0 TO Breadth / 2 ' Red: flood fill iteratively FOR DIM y = 0 TO Height / 2 IF NOT POINT(FBSL.GETDC, x, y) THEN PSET(FBSL.GETDC, x, y, &HFF) NEXT NEXT FBSLSETTEXT(ME, "After Flood Fill") ' Reset form caption END SUB   SUB DrawCircles() ' Concatenate function calls CIRCLE(FBSL.GETDC, Breadth / 2, Height / 2, 85, &HFFFFFF, 0, 360, 1, TRUE) _ ' White (FBSL.GETDC, Breadth / 3, Height / 3, 30, 0, 0, 360, 1, TRUE) ' Black END SUB
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#F.23
F#
type bool = System.Boolean
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#Factor
Factor
TRUE . \ -1 FALSE . \ 0
http://rosettacode.org/wiki/Caesar_cipher
Caesar cipher
Task Implement a Caesar cipher, both encoding and decoding. The key is an integer from 1 to 25. This cipher rotates (either towards left or right) the letters of the alphabet (A to Z). The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A). So key 2 encrypts "HI" to "JK", but key 20 encrypts "HI" to "BC". This simple "mono-alphabetic substitution cipher" provides almost no security, because an attacker who has the encoded message can either use frequency analysis to guess the key, or just try all 25 keys. Caesar cipher is identical to Vigenère cipher with a key of length 1. Also, Rot-13 is identical to Caesar cipher with key 13. Related tasks Rot-13 Substitution Cipher Vigenère Cipher/Cryptanalysis
#VBScript
VBScript
  str = "IT WAS THE BEST OF TIMES, IT WAS THE WORST OF TIMES."   Wscript.Echo str Wscript.Echo Rotate(str,5) Wscript.Echo Rotate(Rotate(str,5),-5)   'Rotate (Caesar encrypt/decrypt) test <numpos> positions. ' numpos < 0 - rotate left ' numpos > 0 - rotate right 'Left rotation is converted to equivalent right rotation Function Rotate (text, numpos)   dim dic: set dic = CreateObject("Scripting.Dictionary") dim ltr: ltr = Split("A B C D E F G H I J K L M N O P Q R S T U V W X Y Z") dim rot: rot = (26 + numpos Mod 26) Mod 26 'convert all to right rotation dim ch dim i   for i = 0 to ubound(ltr) dic(ltr(i)) = ltr((rot+i) Mod 26) next   Rotate = ""   for i = 1 to Len(text) ch = Mid(text,i,1) if dic.Exists(ch) Then Rotate = Rotate & dic(ch) else Rotate = Rotate & ch end if next   End Function  
http://rosettacode.org/wiki/Box_the_compass
Box the compass
There be many a land lubber that knows naught of the pirate ways and gives direction by degree! They know not how to box the compass! Task description Create a function that takes a heading in degrees and returns the correct 32-point compass heading. Use the function to print and display a table of Index, Compass point, and Degree; rather like the corresponding columns from, the first table of the wikipedia article, but use only the following 33 headings as input: [0.0, 16.87, 16.88, 33.75, 50.62, 50.63, 67.5, 84.37, 84.38, 101.25, 118.12, 118.13, 135.0, 151.87, 151.88, 168.75, 185.62, 185.63, 202.5, 219.37, 219.38, 236.25, 253.12, 253.13, 270.0, 286.87, 286.88, 303.75, 320.62, 320.63, 337.5, 354.37, 354.38]. (They should give the same order of points but are spread throughout the ranges of acceptance). Notes; The headings and indices can be calculated from this pseudocode: for i in 0..32 inclusive: heading = i * 11.25 case i %3: if 1: heading += 5.62; break if 2: heading -= 5.62; break end index = ( i mod 32) + 1 The column of indices can be thought of as an enumeration of the thirty two cardinal points (see talk page)..
#D
D
import std.stdio, std.string, std.math, std.array;   struct boxTheCompass { immutable static string[32] points;   pure nothrow static this() { immutable cardinal = ["north", "east", "south", "west"]; immutable desc = ["1", "1 by 2", "1-C", "C by 1", "C", "C by 2", "2-C", "2 by 1"];   foreach (immutable i; 0 .. 4) { immutable s1 = cardinal[i]; immutable s2 = cardinal[(i + 1) % 4]; immutable sc = (s1 == "north" || s1 == "south") ? (s1 ~ s2) : (s2 ~ s1); foreach (immutable j; 0 .. 8) points[i * 8 + j] = desc[j].replace("1", s1). replace("2", s2).replace("C", sc); } }   static string opCall(in double degrees) pure /*nothrow*/ { immutable testD = (degrees / 11.25) + 0.5; return points[cast(int)floor(testD % 32)].capitalize; } }   void main() { foreach (immutable i; 0 .. 33) { immutable heading = i * 11.25 + [0, 5.62, -5.62][i % 3]; writefln("%s\t%18s\t%s", i % 32 + 1, heading.boxTheCompass, heading); } }
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, where N is the image width and M is the image height. Test task Histogram is useful for many image processing operations. As an example, use it to convert an image into black and white art. The method works as follows: Convert image to grayscale; Compute the histogram Find the median: defined as the luminance such that the image has an approximately equal number of pixels with lesser and greater luminance. Replace each pixel of luminance lesser than the median to black, and others to white. Use read/write ppm file, and grayscale image solutions.
#Tcl
Tcl
package require Tcl 8.5 package require Tk   proc convert_to_blackandwhite {filename} { set img [image create photo] readPPM $img $filename grayscale $img set hist [histogram $img] set median [median $img $hist] blackandwhite $img $median output_ppm $img bw_$filename }   proc histogram {image} { set hist [dict create] for {set x 0} {$x < [image width $image]} {incr x} { for {set y 0} {$y < [image height $image]} {incr y} { dict incr hist [luminance {*}[$image get $x $y]] } } return $hist }   proc luminance {r g b} { expr { int(0.2126*$r + 0.7152*$g + 0.0722*$b) } }   proc median {img hist} { set sum [expr {[image width $img] * [image height $img]}] set total 0 foreach luminance [lsort -integer [dict keys $hist]] { incr total [dict get $hist $luminance] if {$total > $sum / 2} break } return $luminance }   proc blackandwhite {image median} { for {set x 0} {$x < [image width $image]} {incr x} { for {set y 0} {$y < [image height $image]} {incr y} { if {[luminance {*}[$image get $x $y]] < $median} { $image put black -to $x $y } else { $image put white -to $x $y } } } }
http://rosettacode.org/wiki/Bitwise_operations
Bitwise operations
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation | Comparison | Matching Memory Operations Pointers & references | Addresses Task Write a routine to perform a bitwise AND, OR, and XOR on two integers, a bitwise NOT on the first integer, a left shift, right shift, right arithmetic shift, left rotate, and right rotate. All shifts and rotates should be done on the first integer with a shift/rotate amount of the second integer. If any operation is not available in your language, note it.
#AutoHotkey
AutoHotkey
bitwise(3, 4) bitwise(a, b) { MsgBox % "a and b: " . a & b MsgBox % "a or b: " . a | b MsgBox % "a xor b: " . a ^ b MsgBox % "not a: " . ~a ; treated as unsigned integer MsgBox % "a << b: " . a << b ; left shift MsgBox % "a >> b: " . a >> b ; arithmetic right shift }
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#XPL0
XPL0
include c:\cxpl\codes; \intrinsic 'code' declarations   proc Bezier(P0, P1, P2); \Draw quadratic Bezier curve real P0, P1, P2; def Segments = 8; int I; real T, A, B, C, X, Y; [Move(fix(P0(0)), fix(P0(1))); for I:= 1 to Segments do [T:= float(I)/float(Segments); A:= sq(1.-T); B:= 2.*T*(1.-T); C:= sq(T); X:= A*P0(0) + B*P1(0) + C*P2(0); Y:= A*P0(1) + B*P1(1) + C*P2(1); Line(fix(X), fix(Y), $00FFFF); \cyan line segments ]; Point(fix(P0(0)), fix(P0(1)), $FF0000); \red control points Point(fix(P1(0)), fix(P1(1)), $FF0000); Point(fix(P2(0)), fix(P2(1)), $FF0000); ];   [SetVid($112); \set 640x480x24 video graphics Bezier([0., 0.], [80., 100.], [160., 20.]); if ChIn(1) then []; \wait for keystroke SetVid(3); \restore normal text display ]
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#zkl
zkl
fcn qBezier(p0x,p0y, p1x,p1y, p2x,p2y, rgb, numPts=500){ numPts.pump(Void,'wrap(t){ // B(t) t=t.toFloat()/numPts; t1:=(1.0 - t); a:=t1*t1; b:=t*t1*2; c:=t*t; x:=a*p0x + b*p1x + c*p2x + 0.5; y:=a*p0y + b*p1y + c*p2y + 0.5; __sSet(rgb,x,y); }); }
http://rosettacode.org/wiki/Bitmap
Bitmap
Show a basic storage type to handle a simple RGB raster graphics image, and some primitive associated functions. If possible provide a function to allocate an uninitialised image, given its width and height, and provide 3 additional functions:   one to fill an image with a plain RGB color,   one to set a given pixel with a color,   one to get the color of a pixel. (If there are specificities about the storage or the allocation, explain those.) These functions are used as a base for the articles in the category raster graphics operations, and a basic output function to check the results is available in the article write ppm file.
#Action.21
Action!
INCLUDE "H6:RGBIMAGE.ACT" ;from task Bitmap   RGB black,yellow,violet,blue   PROC DrawImage(RgbImage POINTER img BYTE x,y) RGB c BYTE i,j   FOR j=0 TO img.h-1 DO FOR i=0 TO img.w-1 DO GetRgbPixel(img,i,j,c) IF RgbEqual(c,yellow) THEN Color=1 ELSEIF RgbEqual(c,violet) THEN Color=2 ELSEIF RgbEqual(c,blue) THEN Color=3 ELSE Color=0 FI Plot(x+i,y+j) OD OD RETURN   PROC Main() RgbImage img BYTE CH=$02FC,width=[80],height=[60] BYTE ARRAY ptr(14400) BYTE i,x,y,c   Graphics(7+16) SetColor(0,13,12) ;yellow SetColor(1,4,10)  ;violet SetColor(2,8,6)  ;blue SetColor(4,0,0)  ;black   RgbBlack(black) RgbYellow(yellow) RgbViolet(violet) RgbBlue(blue)   InitRgbImage(img,width,height,ptr) FillRgbImage(img,blue)   FOR i=1 TO 1000 DO c=Rand(3) x=Rand(width) y=Rand(height) IF c=0 THEN SetRgbPixel(img,x,y,yellow) ELSEIF c=1 THEN SetRgbPixel(img,x,y,violet) ELSE SetRgbPixel(img,x,y,black) FI OD   DrawImage(img,(160-width)/2,(96-height)/2)   DO UNTIL CH#$FF OD CH=$FF RETURN
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#Nim
Nim
import bitmap   proc setPixel(img: Image; x, y: int; color: Color) {.inline.} = # Set a pixel at a given color. # Ignore if the point is outside of the image. if x in 0..<img.w and y in 0..<img.h: img[x, y] = color     proc drawCircle(img: Image; center: Point; radius: Natural; color: Color) = ## Draw a circle using midpoint circle algorithm.   var f = 1 - radius ddFX = 0 ddFY = -2 * radius x = 0 y = radius   img.setPixel(center.x, center.y + radius, color) img.setPixel(center.x, center.y - radius, color) img.setPixel(center.x + radius, center.y, color) img.setPixel(center.x - radius, center.y, color)   while x < y: if f >= 0: dec y inc ddFY, 2 inc f, ddFY inc x inc ddFX, 2 inc f, ddFX + 1   img.setPixel(center.x + x, center.y + y, color) img.setPixel(center.x - x, center.y + y, color) img.setPixel(center.x + x, center.y - y, color) img.setPixel(center.x - x, center.y - y, color) img.setPixel(center.x + y, center.y + x, color) img.setPixel(center.x - y, center.y + x, color) img.setPixel(center.x + y, center.y - x, color) img.setPixel(center.x - y, center.y - x, color)   #———————————————————————————————————————————————————————————————————————————————————————————————————   when isMainModule: var img = newImage(16, 16) img.fill(White) img.drawCircle((7, 7), 5, Black) img.print()
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#Perl
Perl
# 20220301 Perl programming solution   use strict; use warnings;   use Algorithm::Line::Bresenham 'circle';   my @points; my @circle = circle((10) x 3);   for (@circle) { $points[$_->[0]][$_->[1]] = '#' }   print join "\n", map { join '', map { $_ || ' ' } @$_ } @points
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#Julia
Julia
using Images   function cubicbezier!(xy::Matrix, img::Matrix = fill(RGB(255.0, 255.0, 255.0), 17, 17), col::ColorTypes.Color = convert(eltype(img), Gray(0.0)), n::Int = 20) t = collect(0:n) ./ n M = hcat((1 .- t) .^ 3, # a 3t .* (1 .- t) .^ 2, # b 3t .^ 2 .* (1 .- t), # c t .^ 3) # d p = floor.(Int, M * xy) for i in 1:n drawline!(img, p[i, :]..., p[i+1, :]..., col) end return img end   xy = [16 1; 1 4; 3 16; 15 11] cubicbezier!(xy)
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#Kotlin
Kotlin
// Version 1.2.40   import java.awt.Color import java.awt.Graphics import java.awt.image.BufferedImage import kotlin.math.abs import java.io.File import javax.imageio.ImageIO   class Point(var x: Int, var y: Int)   class BasicBitmapStorage(width: Int, height: Int) { val image = BufferedImage(width, height, BufferedImage.TYPE_3BYTE_BGR)   fun fill(c: Color) { val g = image.graphics g.color = c g.fillRect(0, 0, image.width, image.height) }   fun setPixel(x: Int, y: Int, c: Color) = image.setRGB(x, y, c.getRGB())   fun getPixel(x: Int, y: Int) = Color(image.getRGB(x, y))   fun drawLine(x0: Int, y0: Int, x1: Int, y1: Int, c: Color) { val dx = abs(x1 - x0) val dy = abs(y1 - y0) val sx = if (x0 < x1) 1 else -1 val sy = if (y0 < y1) 1 else -1 var xx = x0 var yy = y0 var e1 = (if (dx > dy) dx else -dy) / 2 var e2: Int while (true) { setPixel(xx, yy, c) if (xx == x1 && yy == y1) break e2 = e1 if (e2 > -dx) { e1 -= dy; xx += sx } if (e2 < dy) { e1 += dx; yy += sy } } }   fun cubicBezier(p1: Point, p2: Point, p3: Point, p4: Point, clr: Color, n: Int) { val pts = List(n + 1) { Point(0, 0) } for (i in 0..n) { val t = i.toDouble() / n val u = 1.0 - t val a = u * u * u val b = 3.0 * t * u * u val c = 3.0 * t * t * u val d = t * t * t pts[i].x = (a * p1.x + b * p2.x + c * p3.x + d * p4.x).toInt() pts[i].y = (a * p1.y + b * p2.y + c * p3.y + d * p4.y).toInt() setPixel(pts[i].x, pts[i].y, clr) } for (i in 0 until n) { val j = i + 1 drawLine(pts[i].x, pts[i].y, pts[j].x, pts[j].y, clr) } } }   fun main(args: Array<String>) { val width = 200 val height = 200 val bbs = BasicBitmapStorage(width, height) with (bbs) { fill(Color.cyan) val p1 = Point(0, 149) val p2 = Point(30, 50) val p3 = Point(120, 130) val p4 = Point(160, 30) cubicBezier(p1, p2, p3, p4, Color.black, 20) val cbFile = File("cubic_bezier.jpg") ImageIO.write(image, "jpg", cbFile) } }
http://rosettacode.org/wiki/Biorhythms
Biorhythms
For a while in the late 70s, the pseudoscience of biorhythms was popular enough to rival astrology, with kiosks in malls that would give you your weekly printout. It was also a popular entry in "Things to Do with your Pocket Calculator" lists. You can read up on the history at Wikipedia, but the main takeaway is that unlike astrology, the math behind biorhythms is dead simple. It's based on the number of days since your birth. The premise is that three cycles of unspecified provenance govern certain aspects of everyone's lives – specifically, how they're feeling physically, emotionally, and mentally. The best part is that not only do these cycles somehow have the same respective lengths for all humans of any age, gender, weight, genetic background, etc, but those lengths are an exact number of days. And the pattern is in each case a perfect sine curve. Absolutely miraculous! To compute your biorhythmic profile for a given day, the first thing you need is the number of days between that day and your birth, so the answers in Days between dates are probably a good starting point. (Strictly speaking, the biorhythms start at 0 at the moment of your birth, so if you know time of day you can narrow things down further, but in general these operate at whole-day granularity.) Then take the residue of that day count modulo each of the the cycle lengths to calculate where the day falls on each of the three sinusoidal journeys. The three cycles and their lengths are as follows: Cycle Length Physical 23 days Emotional 28 days Mental 33 days The first half of each cycle is in "plus" territory, with a peak at the quarter-way point; the second half in "minus" territory, with a valley at the three-quarters mark. You can calculate a specific value between -1 and +1 for the kth day of an n-day cycle by computing sin( 2πk / n ). The days where a cycle crosses the axis in either direction are called "critical" days, although with a cycle value of 0 they're also said to be the most neutral, which seems contradictory. The task: write a subroutine, function, or program that will, given a birthdate and a target date, output the three biorhythmic values for the day. You may optionally include a text description of the position and the trend (e.g. "up and rising", "peak", "up but falling", "critical", "down and falling", "valley", "down but rising"), an indication of the date on which the next notable event (peak, valley, or crossing) falls, or even a graph of the cycles around the target date. Demonstrate the functionality for dates of your choice. Example run of my Raku implementation: raku br.raku 1943-03-09 1972-07-11 Output: Day 10717: Physical day 22: -27% (down but rising, next transition 1972-07-12) Emotional day 21: valley Mental day 25: valley Double valley! This was apparently not a good day for Mr. Fischer to begin a chess tournament...
#Emacs_Lisp
Emacs Lisp
(require 'calendar)   (setq biorhythm-birthdate '(3 16 1953))   (defun biorhythm () "Show today's biorhythm." (interactive) (let* ((diff (abs (- (string-to-number (calendar-astro-date-string biorhythm-birthdate)) (string-to-number (calendar-astro-date-string))))) (rhyt '(23 28 33)) (perc (mapcar (lambda (x) (round (* 100 (sin (* 2 pi diff (/ 1.0 x)))))) rhyt))) (message "age: %i physical: %i%% emotional: %i%% intellectual: %i%%" diff (car perc) (cadr perc) (caddr perc))))
http://rosettacode.org/wiki/Biorhythms
Biorhythms
For a while in the late 70s, the pseudoscience of biorhythms was popular enough to rival astrology, with kiosks in malls that would give you your weekly printout. It was also a popular entry in "Things to Do with your Pocket Calculator" lists. You can read up on the history at Wikipedia, but the main takeaway is that unlike astrology, the math behind biorhythms is dead simple. It's based on the number of days since your birth. The premise is that three cycles of unspecified provenance govern certain aspects of everyone's lives – specifically, how they're feeling physically, emotionally, and mentally. The best part is that not only do these cycles somehow have the same respective lengths for all humans of any age, gender, weight, genetic background, etc, but those lengths are an exact number of days. And the pattern is in each case a perfect sine curve. Absolutely miraculous! To compute your biorhythmic profile for a given day, the first thing you need is the number of days between that day and your birth, so the answers in Days between dates are probably a good starting point. (Strictly speaking, the biorhythms start at 0 at the moment of your birth, so if you know time of day you can narrow things down further, but in general these operate at whole-day granularity.) Then take the residue of that day count modulo each of the the cycle lengths to calculate where the day falls on each of the three sinusoidal journeys. The three cycles and their lengths are as follows: Cycle Length Physical 23 days Emotional 28 days Mental 33 days The first half of each cycle is in "plus" territory, with a peak at the quarter-way point; the second half in "minus" territory, with a valley at the three-quarters mark. You can calculate a specific value between -1 and +1 for the kth day of an n-day cycle by computing sin( 2πk / n ). The days where a cycle crosses the axis in either direction are called "critical" days, although with a cycle value of 0 they're also said to be the most neutral, which seems contradictory. The task: write a subroutine, function, or program that will, given a birthdate and a target date, output the three biorhythmic values for the day. You may optionally include a text description of the position and the trend (e.g. "up and rising", "peak", "up but falling", "critical", "down and falling", "valley", "down but rising"), an indication of the date on which the next notable event (peak, valley, or crossing) falls, or even a graph of the cycles around the target date. Demonstrate the functionality for dates of your choice. Example run of my Raku implementation: raku br.raku 1943-03-09 1972-07-11 Output: Day 10717: Physical day 22: -27% (down but rising, next transition 1972-07-12) Emotional day 21: valley Mental day 25: valley Double valley! This was apparently not a good day for Mr. Fischer to begin a chess tournament...
#Factor
Factor
USING: calendar calendar.parser formatting io kernel math math.constants math.functions ;   : days-between ( ymd-str ymd-str -- n ) [ ymd>timestamp ] bi@ time- duration>days abs ;   : trend ( pos len -- str ) / 4 * floor 3 divisor? "↑" "↓" ? ;   : percent ( pos len -- x ) [ 2pi * ] [ / sin 100 * ] bi* ;   : .day ( days cycle-length day-type -- ) write [ mod ] keep [ drop ] [ percent ] [ trend ] 2tri " day %d: %.1f%%%s\n" printf ;   : .biorhythm ( ymd-str ymd-str -- ) 2dup "Born %s, Target %s\n" printf days-between dup "Day %d\n" printf [ 23 "Physical" .day ] [ 28 "Emotional" .day ] [ 33 "Mental" .day ] tri ;   "1809-02-12" "1863-11-19" .biorhythm
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#zkl
zkl
// convert Windows BMP (bit map) image to PPM   // Read BMP file bmp:=File.stdin.read().howza(0); // BMP to memory (byte bucket), treat as bytes _assert_(bmp[0]==0x42,"Stdin not a BMP file"); width:=bmp.toLittleEndian(18,2,False); height:=bmp.toLittleEndian(22,2,False); // signed println(width," x ",height); bmp.del(0,14 + bmp.toLittleEndian(14,2)); // get rid of header   // Write BMP to PPM image (in memory) ppm:=Data(width*height*3 + 100); // sized byte bucket plus some header slop ppm.write("P6\n#rosettacode BMP to PPM test\n%d %d\n255\n".fmt(width,height)); foreach y in ([height - 1 .. 0,-1]){ // BGR 1 byte each, image is stored upside down bmp[y*width*3,width*3].pump(ppm,T(Void.Read,2),fcn(b,g,r){ return(r,g,b) }); }   File("foo.ppm","wb").write(ppm); // File.stdout isn't binary, let GC close file
http://rosettacode.org/wiki/Bitmap/Bresenham%27s_line_algorithm
Bitmap/Bresenham's line algorithm
Task Using the data storage type defined on the Bitmap page for raster graphics images, draw a line given two points with Bresenham's line algorithm.
#AutoHotkey
AutoHotkey
Blue := Color(0,0,255) White := Color(255,255,255) Bitmap := Bitmap(100,100,Blue) ;create a 100*100 blue bitmap Line(Bitmap,White,5,10,60,80) ;draw a white line from (5,10) to (60,80) Bitmap.Write("Line.ppm") ;write the bitmap to file   Line(ByRef Bitmap,ByRef Color,PosX1,PosY1,PosX2,PosY2) { DeltaX := Abs(PosX2 - PosX1), DeltaY := -Abs(PosY2 - PosY1) ;calculate deltas StepX := ((PosX1 < PosX2) ? 1 : -1), StepY := ((PosY1 < PosY2) ? 1 : -1) ;calculate steps ErrorValue := DeltaX + DeltaY ;calculate error value Loop ;loop over the pixel values { Bitmap[PosX1,PosX2] := Color If (PosX1 = PosX2 && PosY1 = PosY2) Break Temp1 := ErrorValue << 1, ((Temp1 > DeltaY) ? (ErrorValue += DeltaY, PosX1 += StepX) : ""), ((Temp1 < DeltaX) ? (ErrorValue += DeltaX, PosY1 += StepY) : "") ;move forward } }
http://rosettacode.org/wiki/Bioinformatics/Sequence_mutation
Bioinformatics/Sequence mutation
Task Given a string of characters A, C, G, and T representing a DNA sequence write a routine to mutate the sequence, (string) by: Choosing a random base position in the sequence. Mutate the sequence by doing one of either: Swap the base at that position by changing it to one of A, C, G, or T. (which has a chance of swapping the base for the same base) Delete the chosen base at the position. Insert another base randomly chosen from A,C, G, or T into the sequence at that position. Randomly generate a test DNA sequence of at least 200 bases "Pretty print" the sequence and a count of its size, and the count of each base in the sequence Mutate the sequence ten times. "Pretty print" the sequence after all mutations, and a count of its size, and the count of each base in the sequence. Extra credit Give more information on the individual mutations applied. Allow mutations to be weighted and/or chosen.
#Arturo
Arturo
bases: ["A" "T" "G" "C"] dna: map 1..200 => [sample bases]   prettyPrint: function [in][ count: #[ A: 0, T: 0, G: 0, C: 0 ]   loop.with:'i split.every:50 in 'line [ prints [pad to :string i*50 3 ":"] print map split.every:10 line => join   loop split line 'ch [ case [ch=] when? -> "A" -> count\A: count\A + 1 when? -> "T" -> count\T: count\T + 1 when? -> "G" -> count\G: count\G + 1 when? -> "C" -> count\C: count\C + 1 else [] ] ] print ["Total count => A:" count\A, "T:" count\T "G:" count\G "C:" count\C] ]   performRandomModifications: function [seq,times][ result: new seq   loop times [x][ what: random 1 3 case [what=] when? -> 1 [ ind: random 0 (size result) previous: get result ind next: sample bases set result ind next print ["changing base at position" ind "from" previous "to" next] ] when? -> 2 [ ind: random 0 (size result) next: sample bases result: insert result ind next print ["inserting base" next "at position" ind] ] else [ ind: random 0 (size result) previous: get result ind result: remove result .index ind print ["deleting base" previous "at position" ind] ] ] return result ]   print "------------------------------" print " Initial sequence" print "------------------------------" prettyPrint dna print ""   print "------------------------------" print " Modifying sequence" print "------------------------------" dna: performRandomModifications dna 10 print ""   print "------------------------------" print " Final sequence" print "------------------------------" prettyPrint dna print ""
http://rosettacode.org/wiki/Bitcoin/address_validation
Bitcoin/address validation
Bitcoin/address validation You are encouraged to solve this task according to the task description, using any language you may know. Task Write a program that takes a bitcoin address as argument, and checks whether or not this address is valid. A bitcoin address uses a base58 encoding, which uses an alphabet of the characters 0 .. 9, A ..Z, a .. z, but without the four characters:   0   zero   O   uppercase oh   I   uppercase eye   l   lowercase ell With this encoding, a bitcoin address encodes 25 bytes: the first byte is the version number, which will be zero for this task ; the next twenty bytes are a RIPEMD-160 digest, but you don't have to know that for this task: you can consider them a pure arbitrary data ; the last four bytes are a checksum check. They are the first four bytes of a double SHA-256 digest of the previous 21 bytes. To check the bitcoin address, you must read the first twenty-one bytes, compute the checksum, and check that it corresponds to the last four bytes. The program can either return a boolean value or throw an exception when not valid. You can use a digest library for SHA-256. Example of a bitcoin address 1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62i It doesn't belong to anyone and is part of the test suite of the bitcoin software. You can change a few characters in this string and check that it'll fail the test.
#Erlang
Erlang
  -module( bitcoin_address ).   -export( [task/0, validate/1] ).   task() -> io:fwrite( "Validate ~p~n", ["1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62i"] ), io:fwrite( "~p~n", [validate("1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62i")] ), io:fwrite( "Validate ~p~n", ["1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW622"] ), io:fwrite( "~p~n", [validate("1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW622")] ).   validate( String ) -> {length_25, <<Address:21/binary, Checksum:4/binary>>} = {length_25, base58:base58_to_binary( String )}, <<Version:1/binary, _/binary>> = Address, {version_0, <<0>>} = {version_0, Version}, <<Four_bytes:4/binary, _T/binary>> = crypto:hash( sha256, crypto:hash(sha256, Address) ), {checksum, Checksum} = {checksum, Four_bytes}, ok.  
http://rosettacode.org/wiki/Bitcoin/public_point_to_address
Bitcoin/public point to address
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion. The encoding steps are: take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed string ; add one byte prefix equal to 4 (it is a convention for this way of encoding a public point) ; compute the SHA-256 of this string ; compute the RIPEMD-160 of this SHA-256 digest ; compute the checksum of the concatenation of the version number digit (a single zero byte) and this RIPEMD-160 digest, as described in bitcoin/address validation ; Base-58 encode (see below) the concatenation of the version number (zero in this case), the ripemd digest and the checksum The base-58 encoding is based on an alphabet of alphanumeric characters (numbers, upper case and lower case, in that order) but without the four characters 0, O, l and I. Here is an example public point: X = 0x50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352 Y = 0x2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6 The corresponding address should be: 16UwLL9Risc3QfPqBUvKofHmBQ7wMtjvM Nb. The leading '1' is not significant as 1 is zero in base-58. It is however often added to the bitcoin address for various reasons. There can actually be several of them. You can ignore this and output an address without the leading 1. Extra credit: add a verification procedure about the public point, making sure it belongs to the secp256k1 elliptic curve
#PicoLisp
PicoLisp
(load "ripemd160.l") (load "sha256.l")   (setq *B58Alpha (chop "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz") ) (de hex2L (H) (make (for (L (chop H) L (cddr L)) (link (hex (pack (car L) (cadr L)))) ) ) ) (de b58enc (Lst) (let (P 1 Z 0 A (sum '((X) (* X (swap 'P (>> -8 P))) ) (reverse Lst) ) ) (for L Lst (T (n0 L)) (inc 'Z) ) (pack (need Z "1") (make (while (gt0 A) (yoke (prog1 (get *B58Alpha (inc (% A 58))) (setq A (/ A 58)) ) ) ) ) ) ) ) (de point2address (X Y) (let L (conc (cons 4) (hex2L X) (hex2L Y)) (b58enc (and (conc (cons 0) (ripemd160 (sha256 L))) (conc @ (head 4 (sha256 (sha256 @)))) ) ) ) ) (println (point2address "50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352" "2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6" ) )
http://rosettacode.org/wiki/Bitcoin/public_point_to_address
Bitcoin/public point to address
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion. The encoding steps are: take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed string ; add one byte prefix equal to 4 (it is a convention for this way of encoding a public point) ; compute the SHA-256 of this string ; compute the RIPEMD-160 of this SHA-256 digest ; compute the checksum of the concatenation of the version number digit (a single zero byte) and this RIPEMD-160 digest, as described in bitcoin/address validation ; Base-58 encode (see below) the concatenation of the version number (zero in this case), the ripemd digest and the checksum The base-58 encoding is based on an alphabet of alphanumeric characters (numbers, upper case and lower case, in that order) but without the four characters 0, O, l and I. Here is an example public point: X = 0x50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352 Y = 0x2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6 The corresponding address should be: 16UwLL9Risc3QfPqBUvKofHmBQ7wMtjvM Nb. The leading '1' is not significant as 1 is zero in base-58. It is however often added to the bitcoin address for various reasons. There can actually be several of them. You can ignore this and output an address without the leading 1. Extra credit: add a verification procedure about the public point, making sure it belongs to the secp256k1 elliptic curve
#Python
Python
#!/usr/bin/env python3   import binascii import functools import hashlib   digits58 = b'123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'   def b58(n): return b58(n//58) + digits58[n%58:n%58+1] if n else b''   def public_point_to_address(x, y): c = b'\x04' + binascii.unhexlify(x) + binascii.unhexlify(y) r = hashlib.new('ripemd160') r.update(hashlib.sha256(c).digest()) c = b'\x00' + r.digest() d = hashlib.sha256(hashlib.sha256(c).digest()).digest() return b58(functools.reduce(lambda n, b: n<<8|b, c + d[:4]))   if __name__ == '__main__': print(public_point_to_address( b'50863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B2352', b'2CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6'))
http://rosettacode.org/wiki/Bitmap/Flood_fill
Bitmap/Flood fill
Implement a flood fill. A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point towards the banks (or: inside the valley): if there's a hole in the banks, the flood is not contained and all the image (or all the "connected valleys") get filled. To accomplish the task, you need to implement just one of the possible algorithms (examples are on Wikipedia). Variations on the theme are allowed (e.g. adding a tolerance parameter or argument for color-matching of the banks or target color). Testing: the basic algorithm is not suitable for truecolor images; a possible test image is the one shown on the right box; you can try to fill the white area, or the black inner circle.
#Forth
Forth
: third 2 pick ; : 3dup third third third ; : 4dup 2over 2over ;   : flood ( color x y bmp -- ) 3dup b@ >r ( R: color to fill ) 4dup b! third 0 > if rot 1- -rot 3dup b@ r@ = if recurse then rot 1+ -rot then third 1+ over bwidth < if rot 1+ -rot 3dup b@ r@ = if recurse then rot 1- -rot then over 0 > if swap 1- swap 3dup b@ r@ = if recurse then swap 1+ swap then over 1+ over bheight < if swap 1+ swap 3dup b@ r@ = if recurse then swap 1- swap then r> drop ;
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#FALSE
FALSE
TRUE . \ -1 FALSE . \ 0
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#Fantom
Fantom
TRUE . \ -1 FALSE . \ 0
http://rosettacode.org/wiki/Caesar_cipher
Caesar cipher
Task Implement a Caesar cipher, both encoding and decoding. The key is an integer from 1 to 25. This cipher rotates (either towards left or right) the letters of the alphabet (A to Z). The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A). So key 2 encrypts "HI" to "JK", but key 20 encrypts "HI" to "BC". This simple "mono-alphabetic substitution cipher" provides almost no security, because an attacker who has the encoded message can either use frequency analysis to guess the key, or just try all 25 keys. Caesar cipher is identical to Vigenère cipher with a key of length 1. Also, Rot-13 is identical to Caesar cipher with key 13. Related tasks Rot-13 Substitution Cipher Vigenère Cipher/Cryptanalysis
#Vedit_macro_language
Vedit macro language
#10 = Get_Num("Enter the key: positive to cipher, negative to de-cipher: ", STATLINE)   Goto_Pos(Block_Begin) while(Cur_Pos < Block_End) { #11 = Cur_Char & 0x60 + 1 if (Cur_Char >= 'A') { Ins_Char((Cur_Char - #11 + 26 + #10) % 26 + #11, OVERWRITE) } else { Char(1) } }
http://rosettacode.org/wiki/Box_the_compass
Box the compass
There be many a land lubber that knows naught of the pirate ways and gives direction by degree! They know not how to box the compass! Task description Create a function that takes a heading in degrees and returns the correct 32-point compass heading. Use the function to print and display a table of Index, Compass point, and Degree; rather like the corresponding columns from, the first table of the wikipedia article, but use only the following 33 headings as input: [0.0, 16.87, 16.88, 33.75, 50.62, 50.63, 67.5, 84.37, 84.38, 101.25, 118.12, 118.13, 135.0, 151.87, 151.88, 168.75, 185.62, 185.63, 202.5, 219.37, 219.38, 236.25, 253.12, 253.13, 270.0, 286.87, 286.88, 303.75, 320.62, 320.63, 337.5, 354.37, 354.38]. (They should give the same order of points but are spread throughout the ranges of acceptance). Notes; The headings and indices can be calculated from this pseudocode: for i in 0..32 inclusive: heading = i * 11.25 case i %3: if 1: heading += 5.62; break if 2: heading -= 5.62; break end index = ( i mod 32) + 1 The column of indices can be thought of as an enumeration of the thirty two cardinal points (see talk page)..
#Delphi
Delphi
defmodule Box do defp head do Enum.chunk(~w(north east south west north), 2, 1) |> Enum.flat_map(fn [a,b] -> c = if a=="north" or a=="south", do: "#{a}#{b}", else: "#{b}#{a}" [ a, "#{a} by #{b}", "#{a}-#{c}", "#{c} by #{a}", c, "#{c} by #{b}", "#{b}-#{c}", "#{b} by #{a}" ] end) |> Enum.with_index |> Enum.map(fn {s, i} -> {i+1, String.capitalize(s)} end) |> Map.new end   def compass do header = head() angles = Enum.map(0..32, fn i -> i * 11.25 + elem({0, 5.62, -5.62}, rem(i, 3)) end) Enum.each(angles, fn degrees -> index = rem(round(32 * degrees / 360), 32) + 1  :io.format "~2w ~-20s ~6.2f~n", [index, header[index], degrees] end) end end   Box.compass
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, where N is the image width and M is the image height. Test task Histogram is useful for many image processing operations. As an example, use it to convert an image into black and white art. The method works as follows: Convert image to grayscale; Compute the histogram Find the median: defined as the luminance such that the image has an approximately equal number of pixels with lesser and greater luminance. Replace each pixel of luminance lesser than the median to black, and others to white. Use read/write ppm file, and grayscale image solutions.
#Vedit_macro_language
Vedit macro language
:HISTOGRAM: #30 = Buf_Free // #30 = buffer to store histogram data for (#9=0; #9<256; #9++) { Out_Reg(21) TC(#9) Out_Reg(Clear) // @21 = intensity value to be counted Buf_Switch(#15) // switch to image buffer #8 = Search(@21, CASE+BEGIN+ALL+NOERR) // count intensity values Buf_Switch(#30) // switch to histogram buffer Num_Ins(#8, FILL) // store count } Return
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, where N is the image width and M is the image height. Test task Histogram is useful for many image processing operations. As an example, use it to convert an image into black and white art. The method works as follows: Convert image to grayscale; Compute the histogram Find the median: defined as the luminance such that the image has an approximately equal number of pixels with lesser and greater luminance. Replace each pixel of luminance lesser than the median to black, and others to white. Use read/write ppm file, and grayscale image solutions.
#Wren
Wren
import "dome" for Window import "graphics" for Canvas, Color, ImageData   class ImageHistogram { construct new(filename, filename2) { _image = ImageData.loadFromFile(filename) Window.resize(_image.width, _image.height) Canvas.resize(_image.width, _image.height) Window.title = filename2 _image2 = ImageData.create("Grayscale", _image.width, _image.height) _image3 = ImageData.create("B & W", _image.width, _image.height) }   init() { toGrayScale() var h = histogram var m = median(h) toBlackAndWhite(m) _image3.draw(0, 0) _image3.saveToFile(Window.title) }   luminance(c) { (0.2126 * c.r + 0.7152 * c.g + 0.0722 * c.b).floor }   toGrayScale() { for (x in 0..._image.width) { for (y in 0..._image.height) { var c1 = _image.pget(x, y) var lumin = luminance(c1) var c2 = Color.rgb(lumin, lumin, lumin, c1.a) _image2.pset(x, y, c2) } } }   toBlackAndWhite(median) { for (x in 0..._image2.width) { for (y in 0..._image2.height) { var c = _image2.pget(x, y) var lum = luminance(c) if (lum < median) { _image3.pset(x, y, Color.black) } else { _image3.pset(x, y, Color.white) } } } }   histogram { var h = List.filled(256, 0) for (x in 0..._image2.width) { for (y in 0..._image2.height) { var c = _image2.pget(x, y) var lum = luminance(c) h[lum] = h[lum] + 1 } } return h }   median(h) { var lSum = 0 var rSum = 0 var left = 0 var right = 255 while (true) { if (lSum < rSum) { lSum = lSum + h[left] left = left + 1 } else { rSum = rSum + h[right] right = right - 1 } if (left == right) break } return left }   update() {}   draw(alpha) {} }   var Game = ImageHistogram.new("Lenna100.jpg", "Lenna100_B&W.png")
http://rosettacode.org/wiki/Bitwise_operations
Bitwise operations
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation | Comparison | Matching Memory Operations Pointers & references | Addresses Task Write a routine to perform a bitwise AND, OR, and XOR on two integers, a bitwise NOT on the first integer, a left shift, right shift, right arithmetic shift, left rotate, and right rotate. All shifts and rotates should be done on the first integer with a shift/rotate amount of the second integer. If any operation is not available in your language, note it.
#AutoIt
AutoIt
bitwise(255, 5) Func bitwise($a, $b) MsgBox(1, '', _ $a & " AND " & $b & ": " & BitAND($a, $b) & @CRLF & _ $a & " OR " & $b & ": " & BitOR($a, $b) & @CRLF & _ $a & " XOR " & $b & ": " & BitXOR($a, $b) & @CRLF & _ "NOT " & $a & ": " & BitNOT($a) & @CRLF & _ $a & " SHL " & $b & ": " & BitShift($a, $b * -1) & @CRLF & _ $a & " SHR " & $b & ": " & BitShift($a, $b) & @CRLF & _ $a & " ROL " & $b & ": " & BitRotate($a, $b) & @CRLF & _ $a & " ROR " & $b & ": " & BitRotate($a, $b * -1) & @CRLF ) EndFunc
http://rosettacode.org/wiki/Bitmap
Bitmap
Show a basic storage type to handle a simple RGB raster graphics image, and some primitive associated functions. If possible provide a function to allocate an uninitialised image, given its width and height, and provide 3 additional functions:   one to fill an image with a plain RGB color,   one to set a given pixel with a color,   one to get the color of a pixel. (If there are specificities about the storage or the allocation, explain those.) These functions are used as a base for the articles in the category raster graphics operations, and a basic output function to check the results is available in the article write ppm file.
#ActionScript
ActionScript
  // To import the BitmapData class: import flash.display.BitmapData;   // Creates a new BitmapData object with a width of 500 pixels and a height of 300 pixels. var bitmap:BitmapData = new BitmapData(500, 300);   // Create a BitmapData with transparency disallowed var opaqueBitmap:BitmapData = new BitmapData(500, 300, false);   // Bitmap with initial fill colour, as 0xAARRGGBB (default is white) var redFilledBitmap:BitmapData = new BitmapData(400, 300, true, 0xFFFF0000);   // Get the colour value of the pixel at point (200, 200) bitmap.getPixel(200, 200) // As 0xRRGGBB bitmap.getPixel32(200, 200) // As 0xAARRGGBB   // Set the colour value of the pixel at point (300, 200) to blue bitmap.setPixel(300, 200, 0x0000FF); // As 0xRRGGBB bitmap.setPixel32(300, 200, 0xFF0000FF); // As 0xAARRGGBB   // Fill the bitmap with a given colour (as 0xAARRGGBB) after construction bitmap.fillRect(bitmap.rect, 0xFF44FF44);  
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#Phix
Phix
-- demo\rosetta\Bitmap_Circle.exw (runnable version) include ppm.e -- red, yellow, new_image(), write_ppm() -- (covers above requirements)   function SetPx(sequence img, atom x, y, integer colour) if x>=1 and x<=length(img) and y>=1 and y<=length(img[x]) then img[x][y] = colour end if return img end function   function Circle(sequence img, atom x, y, r, integer colour) atom x1 = -r, y1 = 0, err = 2-2*r if r>=0 then -- Bresenham algorithm while 1 do img = SetPx(img, x-x1, y+y1, colour) img = SetPx(img, x-y1, y-x1, colour) img = SetPx(img, x+x1, y-y1, colour) img = SetPx(img, x+y1, y+x1, colour) r = err if r>x1 then x1 += 1 err += x1*2 + 1 end if if r<=y1 then y1 += 1 err += y1*2 + 1 end if if x1>=0 then exit end if end while end if return img end function   sequence img = new_image(400,300,yellow) img = Circle(img, 200, 150, 100, red) write_ppm("Circle.ppm",img)
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#PicoLisp
PicoLisp
(de midPtCircle (Img CX CY Rad) (let (F (- 1 Rad) DdFx 0 DdFy (* -2 Rad) X 0 Y Rad) (set (nth Img (+ CY Rad) CX) 1) (set (nth Img (- CY Rad) CX) 1) (set (nth Img CY (+ CX Rad)) 1) (set (nth Img CY (- CX Rad)) 1) (while (> Y X) (when (ge0 F) (dec 'Y) (inc 'F (inc 'DdFy 2)) ) (inc 'X) (inc 'F (inc (inc 'DdFx 2))) (set (nth Img (+ CY Y) (+ CX X)) 1) (set (nth Img (+ CY Y) (- CX X)) 1) (set (nth Img (- CY Y) (+ CX X)) 1) (set (nth Img (- CY Y) (- CX X)) 1) (set (nth Img (+ CY X) (+ CX Y)) 1) (set (nth Img (+ CY X) (- CX Y)) 1) (set (nth Img (- CY X) (+ CX Y)) 1) (set (nth Img (- CY X) (- CX Y)) 1) ) ) )   (let Img (make (do 120 (link (need 120 0)))) # Create image 120 x 120 (midPtCircle Img 60 60 50) # Draw circle (out "img.pbm" # Write to bitmap file (prinl "P1") (prinl 120 " " 120) (mapc prinl Img) ) )
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#Lua
Lua
Bitmap.cubicbezier = function(self, x1, y1, x2, y2, x3, y3, x4, y4, nseg) nseg = nseg or 10 local prevx, prevy, currx, curry for i = 0, nseg do local t = i / nseg local a, b, c, d = (1-t)^3, 3*t*(1-t)^2, 3*t^2*(1-t), t^3 prevx, prevy = currx, curry currx = math.floor(a * x1 + b * x2 + c * x3 + d * x4 + 0.5) curry = math.floor(a * y1 + b * y2 + c * y3 + d * y4 + 0.5) if i > 0 then self:line(prevx, prevy, currx, curry) end end end   local bitmap = Bitmap(61,21) bitmap:clear() bitmap:cubicbezier( 1,1, 15,41, 45,-20, 59,19 ) bitmap:render({[0x000000]='.', [0xFFFFFFFF]='X'})
http://rosettacode.org/wiki/Biorhythms
Biorhythms
For a while in the late 70s, the pseudoscience of biorhythms was popular enough to rival astrology, with kiosks in malls that would give you your weekly printout. It was also a popular entry in "Things to Do with your Pocket Calculator" lists. You can read up on the history at Wikipedia, but the main takeaway is that unlike astrology, the math behind biorhythms is dead simple. It's based on the number of days since your birth. The premise is that three cycles of unspecified provenance govern certain aspects of everyone's lives – specifically, how they're feeling physically, emotionally, and mentally. The best part is that not only do these cycles somehow have the same respective lengths for all humans of any age, gender, weight, genetic background, etc, but those lengths are an exact number of days. And the pattern is in each case a perfect sine curve. Absolutely miraculous! To compute your biorhythmic profile for a given day, the first thing you need is the number of days between that day and your birth, so the answers in Days between dates are probably a good starting point. (Strictly speaking, the biorhythms start at 0 at the moment of your birth, so if you know time of day you can narrow things down further, but in general these operate at whole-day granularity.) Then take the residue of that day count modulo each of the the cycle lengths to calculate where the day falls on each of the three sinusoidal journeys. The three cycles and their lengths are as follows: Cycle Length Physical 23 days Emotional 28 days Mental 33 days The first half of each cycle is in "plus" territory, with a peak at the quarter-way point; the second half in "minus" territory, with a valley at the three-quarters mark. You can calculate a specific value between -1 and +1 for the kth day of an n-day cycle by computing sin( 2πk / n ). The days where a cycle crosses the axis in either direction are called "critical" days, although with a cycle value of 0 they're also said to be the most neutral, which seems contradictory. The task: write a subroutine, function, or program that will, given a birthdate and a target date, output the three biorhythmic values for the day. You may optionally include a text description of the position and the trend (e.g. "up and rising", "peak", "up but falling", "critical", "down and falling", "valley", "down but rising"), an indication of the date on which the next notable event (peak, valley, or crossing) falls, or even a graph of the cycles around the target date. Demonstrate the functionality for dates of your choice. Example run of my Raku implementation: raku br.raku 1943-03-09 1972-07-11 Output: Day 10717: Physical day 22: -27% (down but rising, next transition 1972-07-12) Emotional day 21: valley Mental day 25: valley Double valley! This was apparently not a good day for Mr. Fischer to begin a chess tournament...
#FOCAL
FOCAL
1.01 T "Enter birthdate (y,m,d)",! 1.02 ASK Y,M,D 1.03 D 2; S BZ=Z 1.04 T "Enter today's date (y,m,d)",! 1.05 ASK Y,M,D 1.06 D 2; S DI=Z - BZ 1.07 T %6,"Age in days", DI,! 1.08 T "Physical cycle: " 1.09 S L=23; D 3 1.10 T "Emotional cycle: " 1.11 S L=28; D 3 1.12 T "Intellectual cycle: " 1.13 S L=33; D 3 1.14 Q   2.1 S QA = FITR((M + 9) / 12) 2.2 S QB = FITR(275 * M / 9) 2.3 S QC = FITR(7 * (Y + QA) / 4) 2.4 S Z = 367 * Y - QC + QB + D - 730530   3.1 S P = 100 * FSIN(2*3.1415926536*DI/L) 3.2 T %3,P,"%" 3.3 I (FABS(P)-15)4.1,5.1,5.1   4.1 T " CRITICAL",!   5.1 T !
http://rosettacode.org/wiki/Biorhythms
Biorhythms
For a while in the late 70s, the pseudoscience of biorhythms was popular enough to rival astrology, with kiosks in malls that would give you your weekly printout. It was also a popular entry in "Things to Do with your Pocket Calculator" lists. You can read up on the history at Wikipedia, but the main takeaway is that unlike astrology, the math behind biorhythms is dead simple. It's based on the number of days since your birth. The premise is that three cycles of unspecified provenance govern certain aspects of everyone's lives – specifically, how they're feeling physically, emotionally, and mentally. The best part is that not only do these cycles somehow have the same respective lengths for all humans of any age, gender, weight, genetic background, etc, but those lengths are an exact number of days. And the pattern is in each case a perfect sine curve. Absolutely miraculous! To compute your biorhythmic profile for a given day, the first thing you need is the number of days between that day and your birth, so the answers in Days between dates are probably a good starting point. (Strictly speaking, the biorhythms start at 0 at the moment of your birth, so if you know time of day you can narrow things down further, but in general these operate at whole-day granularity.) Then take the residue of that day count modulo each of the the cycle lengths to calculate where the day falls on each of the three sinusoidal journeys. The three cycles and their lengths are as follows: Cycle Length Physical 23 days Emotional 28 days Mental 33 days The first half of each cycle is in "plus" territory, with a peak at the quarter-way point; the second half in "minus" territory, with a valley at the three-quarters mark. You can calculate a specific value between -1 and +1 for the kth day of an n-day cycle by computing sin( 2πk / n ). The days where a cycle crosses the axis in either direction are called "critical" days, although with a cycle value of 0 they're also said to be the most neutral, which seems contradictory. The task: write a subroutine, function, or program that will, given a birthdate and a target date, output the three biorhythmic values for the day. You may optionally include a text description of the position and the trend (e.g. "up and rising", "peak", "up but falling", "critical", "down and falling", "valley", "down but rising"), an indication of the date on which the next notable event (peak, valley, or crossing) falls, or even a graph of the cycles around the target date. Demonstrate the functionality for dates of your choice. Example run of my Raku implementation: raku br.raku 1943-03-09 1972-07-11 Output: Day 10717: Physical day 22: -27% (down but rising, next transition 1972-07-12) Emotional day 21: valley Mental day 25: valley Double valley! This was apparently not a good day for Mr. Fischer to begin a chess tournament...
#Fortran
Fortran
C ------------------------------------------------------------------ PROGRAM BIORHYTHM C ------------------------------------------------------------------ DOUBLE PRECISION GETJD CHARACTER*3 DOW   DOUBLE PRECISION JD0, JD1, JD2, PI2, DIF   INTEGER BYEAR, BMON, BDAY, TYEAR, TMON, TDAY INTEGER I, J, PHY, EMO, MEN, NDAY, DNUM, YR, DOY CHARACTER*3 DNAME CHARACTER*1 GRID, ROW(65) C ------------------------------------------------------------------   PI2 = ACOS(-1.0D0)*2.0D0   WRITE(*,*) 'ENTER YOUR BIRTHDAY YYYY MM DD' READ(*,*) BYEAR, BMON, BDAY   WRITE(*,*) 'ENTER START DATE YYYY MM DD' READ(*,*) TYEAR, TMON, TDAY   WRITE(*,*) 'ENTER NUMBER OF DAYS TO PLOT' READ(*,*) NDAY   JD0 = GETJD( TYEAR, 1, 1 ) JD1 = GETJD( BYEAR, BMON, BDAY ) JD2 = GETJD( TYEAR, TMON, TDAY )   WRITE(*,1010) WRITE(*,1000) DOW(JD1), INT( JD2-JD1 ) WRITE(*,1010) WRITE(*,1020) DO I=1,NDAY DIF = JD2 - JD1 PHY = INT(3.3D1+3.2D1*SIN( PI2 * DIF / 2.3D1 )) EMO = INT(3.3D1+3.2D1*SIN( PI2 * DIF / 2.8D1 )) MEN = INT(3.3D1+3.2D1*SIN( PI2 * DIF / 3.3D1 ))   IF ( PHY.LT.1 ) PHY = 1 IF ( EMO.LT.1 ) EMO = 1 IF ( MEN.LT.1 ) MEN = 1 IF ( PHY.GT.65 ) PHY = 65 IF ( EMO.GT.65 ) EMO = 65 IF ( MEN.GT.65 ) MEN = 65   DNAME = DOW(JD2) DOY = INT(JD2-JD0)+1 IF ( DNAME.EQ.'SUN' ) THEN GRID = '.' ELSE GRID = ' ' END IF DO J=1,65 ROW(J) = GRID END DO ROW(1) = '|' ROW(17) = ':' ROW(33) = '|' ROW(49) = ':' ROW(65) = '|' ROW(PHY) = 'P' ROW(EMO) = 'E' ROW(MEN) = 'M' IF ( PHY.EQ.EMO ) ROW(PHY) = '*' IF ( PHY.EQ.MEN ) ROW(PHY) = '*' IF ( EMO.EQ.MEN ) ROW(EMO) = '*' WRITE(*,1030) ROW,DNAME,DOY JD2 = JD2 + 1.0D0 END DO WRITE(*,1010)   C ------------------------------------------------------------------   1000 FORMAT( 'YOU WERE BORN ON A (', A3, ') YOU WERE ',I0, $ ' DAYS OLD AT THE START.' ) 1010 FORMAT( 75('=') ) 1020 FORMAT( '-1',31X,'0',30X,'+1 DOY' ) 1030 FORMAT( 1X,65A1, 1X, A3, 1X, I3 )   STOP END   C ------------------------------------------------------------------ FUNCTION DOW( JD ) C ------------------------------------------------------------------ C RETURN THE ABBREVIATION FOR THE DAY OF THE WEEK C JD JULIAN DATE - GREATER THAN 1721423.5 (JAN 1, 0001 SATURDAY) C ------------------------------------------------------------------ DOUBLE PRECISION JD INTEGER IDX CHARACTER*3 DOW, NAMES(7) DATA NAMES/'SAT','SUN','MON','TUE','WED','THR','FRI'/   IDX = INT(MODULO(JD-1.721423500D6,7.0D0)+1)   DOW = NAMES(IDX) RETURN END   C ------------------------------------------------------------------ FUNCTION ISGREG( Y, M, D ) C ------------------------------------------------------------------ C IS THIS DATE ON IN THE GREGORIAN CALENDAR C DATES BEFORE OCT 5 1582 ARE JULIAN C DATES AFTER OCT 14 1582 ARE GREGORIAN C DATES OCT 5-14 1582 INCLUSIVE DO NOT EXIST C ------------------------------------------------------------------ C YEAR 1-ANYTHING C MONTH 1-12 C DAY 1-31 C ------------------------------------------------------------------ LOGICAL ISGREG INTEGER Y, M, D C ------------------------------------------------------------------ ISGREG=.TRUE. IF ( Y.LT.1582 ) GOTO 888 IF ( Y.GT.1582 ) GOTO 999 IF ( M.LT.10 ) GOTO 888 IF ( M.GT.10 ) GOTO 999 IF ( D.LT.5 ) GOTO 888 IF ( D.GT.14 ) GOTO 999   WRITE(*,*) Y,M,D,' DOES NOT EXIST' GOTO 999   888 CONTINUE ISGREG=.FALSE. 999 CONTINUE RETURN END   C ------------------------------------------------------------------ FUNCTION GETJD( YEAR, MONTH, DAY ) C ------------------------------------------------------------------ C RETURN THE JULIAN DATE C YEAR 1-ANYTHING C MONTH 1-12 C DAY 1-31 C ------------------------------------------------------------------ DOUBLE PRECISION GETJD INTEGER YEAR, MONTH, DAY INTEGER Y, M, D, A, B, P1, P2 C ------------------------------------------------------------------ DOUBLE PRECISION TEMP LOGICAL ISGREG, IG   IG = ISGREG( YEAR, MONTH, DAY ) Y = YEAR M = MONTH D = DAY   IF (M.LT.3) THEN Y = Y - 1 M = M + 12 ENDIF   IF (IG) THEN A = FLOOR( DBLE(Y) * 1.0D-2 ) B = 2 - A + FLOOR( DBLE(A) * 2.5D-1 ) ELSE A = 0 B = 0 ENDIF   P1 = FLOOR( 3.65250D2 * DBLE(Y + 4716) ) P2 = FLOOR( 3.06001D1 * DBLE(M + 1) )   GETJD = DBLE(P1 + P2 + D + B) - 1.5245D3   RETURN END