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I have created a jsfiddle to demonstrate the problem Basically the blur event runs on clicking the table cell, but if I clear the table and repopulate using jquery the blur event doesnt run any more (code below - also see jsffiddle). Any ideas how I can get the event to fire even after the JS has rewritten the table? HTML >>> <table id="tasksTable"> <tr> <td class="taskQuantityCol" contenteditable="true">Blurred does Run</td> </tr> </table> <button id="refreshButton"> Refresh </button> JAVASCRIPT >>> $(document).ready(function () { $('.taskQuantityCol').blur(function() { console.log("blurred"); }); $('#refreshButton').click(function() { $("#tasksTable > tbody").empty(); $('#tasksTable').append('<tr><td class="taskQuantityCol" contenteditable=\'true\'>Blurred doesnt Run</td>'); }); }); | I have a bit of code where I am looping through all the select boxes on a page and binding a .hover event to them to do a bit of twiddling with their width on mouse on/off. This happens on page ready and works just fine. The problem I have is that any select boxes I add via Ajax or DOM after the initial loop won't have the event bound. I have found this plugin (), but before I add another 5k to my pages with a plugin, I want to see if anyone knows a way to do this, either with jQuery directly or by another option. |
I think we should have anti-badges. They could be implemented as a sort-of punishment for doing stupid things such as; Get -10 score and no upvotes on any post on the meta site for this site. -- Idiocracy Badge, lose 20 rep. Have 2 questions closed as "Not a real question." -- Blasphemy badge, lose 20 rep. Get -50 or more on any one question. -- Troll badge, lose 20 rep. Get all Anti-Badges. -- Forever-Ignorant badge, 10 day ban from posting new questions (maybe not this one...). Does anyone agree with this? I don't think it would end badly and would be a more obvious hint to users that they have to change behavior or be punished. | The idea is to "award" temporal anti-badges for bad behaviour, which will be removed when some kind of penance has been done. [edit One could even include side effect which activate some constraints.] I'll post some examples as answers, feel free to add more. edit Jeff replied I think this may be fine for training a dog who actually should accept you as alpha male and desire your attention, however some people behave "wrong" not because they want attention but simply because a) they don't know better or b) they are indeed mischievous. While group a) should be easily correctable, group b) will take being ignored as sign that they are free to cause <dramatization> havoc </dramatization> as much as they desire. Certainly, they can get banned for that, but anti-badges would at least provide means to put someone on parole. Consider this suggestion as user-ban's little brother |
While it is understandable why he left the Jedi Order (mainly that he lost his faith in the Order and the Republic), is there any information on what led him to joining the Sith - agents of chaos and the Dark Side of the Force? His former Padawan, Qui-Gon Jinn, was famously killed by the Sith; in fact, this was supposedly the impetus for his finally taking the drastic step and leaving the Order entirely. Additionally, much of the corruption and inefficiency in the Republic and the Order's latter day had been due to the machinations of the Sith; the knowledge of Darth Sidious' identity as Chancellor Palpatine would surely have strongly suggested this. So what exactly led Dooku to forsaking the Light entirely and embracing the Dark as a Sith Lord? | Clearly, Dooku / Tyrannus was not being completely honest about his motives. Clearly he desired power, and was willing to kill to get it. But several instances hint at a deeper motivation: His attempted seduction of Obi-Wan on Geonosis, His reaction to Anakin's defeat in the duel, the fact that he was a profoundly respected Jedi before he turned to the dark side. The reaction scene is inexplicable otherwise (unless, of course, you have an explanation). And it seems to me that Christopher Lee was playing it this way regardless... Thoughts? Anything in extended universe or production info? |
I am really confused about the transit visa. I have a 2hr layover in Paris from the US on my way to Prague. DO i need to apply for a transit Visa? | I found many related questions on this site but I am still not sure about the rules. How can I decide if I need a visa to transit? Schengen members as of May 2021 are as follows: Austria Belgium Czech Republic Denmark (excluding Greenland and the Faroe Islands - but an open border with the Schengen Area is maintained) Estonia Finland France (excluding overseas departments and collectivities) Germany Greece Hungary Iceland Italy Latvia Liechtenstein Lithuania Luxembourg Malta Netherlands (excluding Aruba, Curaçao, Sint Maarten and the Caribbean Netherlands) Norway (excluding Svalbard) Poland Portugal Slovakia Slovenia Spain (except Ceuta and Melilla) Sweden Switzerland |
How to compare two date now and date from API example for API 22 September 2020 and date now 01 october 2020 if (this.state.StartDate <= this.state.timeNow) | Can someone suggest a way to compare the values of two dates greater than, less than, and not in the past using JavaScript? The values will be coming from text boxes. |
In the code below e is my dictionary . ee is the shallow copy of my dictionary created by using the copy method. e = {'a': 100, 'b': [1, 2]} ee = e.copy() After the first statement below, the value in ee also changes . e['b'][0] = 'foo' # {'a': 100, 'b': ['foo', 2]} After the below statement, the value in ee does not change. e['a'] = 300 # {'a': 100, 'b': ['foo', 2]} Can anyone explain the reason for the same or provide link to the question if it is already addressed. | What is the difference between a deep copy and a shallow copy? |
As we were told, he only sought out his master because he had no choice. At least, Voldemort thinks so: “And then, not even a year ago, when I had almost abandoned hope, it happened at last... a servant returned to me. Wormtail here, who had faked his own death to escape justice, was driven out of hiding by those he had once counted friends, and decided to return to his master." GoF, The Death Eaters and he's probably right as Peter, once set on finding Voldemort found him in Albania (!) even before the new school term started. So we have Peter living at Hogwarts / at the Weasleys why exactly? To gain information from Arthur, who was a ministry employee to do what...? Wouldn't it be nicer running abroad or polyjuicing himself into someone else or even living as a muggle? Wouldn't it be better than sleep with Percy/Ron and eat leftovers? What was exactly Peter's plan until he was caught by Sirius? To live his life as a rat? | In Prisoner of Azkaban we learn that Sirius Black escapes from Azkaban. At some point we learn that Scabbers is actually Peter Pettigrew (Wormtail). "Scabbers" fakes his own death and escapes from Ron. He did this because he realized that Sirius Black was coming after him. He was one of the Marauders so he knew of the secret passages out of Hogwarts so probably could have left without needing to go past a Dementor. There was quite a bit of time between him faking his own death and the moment he does leave Hogwarts after escaping from Sirius. During that time he knew Sirius was nearby and yet stayed at Hogwarts. With that said why did Scabbers stay within Hogwarts' grounds instead of leaving to find a new home elsewhere? |
I am trying to code up a game where a rectangle moves according to keyboard inputs on the bottom of the screen, and when spacebar is pressed, it releases a bomb implemented by another rectangle being shot up. I have a Bomb class that implements the spacebar initiated bombs. However, whenever I run, I get a nullPointerException error. Code for the two classes is below. Help would be much appreciated. SuperLeaperPro4000 Class: package SuperLeaperPro4000; //need to import this; import java.awt.*; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.*; import java.awt.event.KeyEvent; import java.awt.event.KeyListener; public class SuperLeaperPro4000 extends Canvas implements ActionListener, KeyListener{ //Declare and initialize timer Timer animator = new Timer(1, this); //Global variable declarations //coordinates of first rectangle int x= 0; int y= 900; //velocity variables of first rectangle int velX= 0; int velY= 0; Graphics g; public SuperLeaperPro4000() { //add key listener addKeyListener(this); //enable key listener setFocusable(true); } public static void main(String[] args){ //create a JFrame named Animation; JFrame frame= new JFrame("Animation"); //create a new instance of the scribble class Canvas canvas= new SuperLeaperPro4000(); //set the size of the canvas canvas.setSize(1000, 1000); frame.setResizable(false); //add the canvas frame.add(canvas); //make sure window is maxed frame.pack(); //stop program when closed frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //let the frame be seen frame.setVisible(true); } public void paint (Graphics g) { //draw the rectangle that will move according to keyboard inputs g.drawRect(x, y, 50, 50); animator.start(); } public void actionPerformed(ActionEvent e) { //update x if (x+velX>=0 && x+velX<=950) { x= x + velX; } //update y if (y+velY>=0 && y+velY<=900) { y= y + velY; } repaint(); } //method that gets called whenever user presses keyboard key public void keyPressed(KeyEvent key) { //if user presses left arrow key, update left velocity; if(key.getKeyCode()==KeyEvent.VK_LEFT) { velX= -1; } //if user presses right arrow key, update right velocity; else if (key.getKeyCode()==KeyEvent.VK_RIGHT) { velX= 1; } //if user presses space, go up; if (key.getKeyCode()==KeyEvent.VK_SPACE){ Bomb haymaker= new Bomb(x, y, 10, 10, 0, -5); haymaker.paint(g); } } //method that gets called whenever user releases keyboard key public void keyReleased(KeyEvent key) { //when the user releases the keys, set the velocities back to 0 if(key.getKeyCode()==KeyEvent.VK_LEFT || key.getKeyCode()==KeyEvent.VK_RIGHT) { velX= 0; } } public void keyTyped(KeyEvent key) { } } Bomb Class: package SuperLeaperPro4000; //need to import this; import java.awt.*; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.*; import java.awt.event.KeyEvent; import java.awt.event.KeyListener; public class Bomb extends Canvas { //field values int x; int y; int height; int width; int velX; int velY; //constructor for a bomb public Bomb(int x, int y, int height, int width, int velX, int velY) { this.x= x; this.y= y; this.height= height; this.width= width; this.velX= velX; this.velY= velY; } public void paint(Graphics gs) { gs.drawRect(this.x, this.y, this.height, this.width); } public void fire(int velocity) { this.velX= velocity; } public int getX() { return this.x; } public int getY() { return this.y; } public int getWidth() { return this.width; } public int getHeight() { return this.height; } public int getVelX() { return this.velX; } public int getVelY() { return this.velY; } } | What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them? What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely? |
Assume that $\ 1a_1+2a_2+\cdots+20a_{20}=1, $ where the $a_j$ are real numbers and that these values minimize $[1a_1^2+2a_2^2+\cdots+20a_{20}^2.]$ Find $a_{12}$. Any help would be greatly appreciated. Thanks! | Assume that $$ 1a_1+2a_2+\cdots+na_n=1, $$ where the $a_j$ are real numbers. As a function of $n$, what is the minimum value of $$1a_1^2+2a_2^2+\cdots+na_n^2?$$ |
Once I installed Ubuntu 16.04LTS, followed by Upgrading to Ubuntu 18.04LTS. After all the new Ubuntu 18.04LTS package get downloaded, Unfortunately new Installation get Interrupted. When I tried to power on my computer it gives back the black screen with message dpkg failed. How can i restore the Installation? | During the upgrade, my computer shut down. After starting it I see a black screen with [OK] sentences with finished tasks after them. The last one is: [OK] Started GNOME display Manager. Dispatcher Service...ed database.s.pp link was shut down... Do I need to format my computer? If not, what else can I do? |
Please, I am writing a scientific paper and I use latex. I have some figures to draw and insert it into the paper. I would like to benefit from your experience. What tool I can use to draw my figures (diagrams) efficiently. Thank you. Best Regards. | What packages do you use and recommend for creating graphics in your LaTeX documents? As this is a community wiki post, please add your package to the accepted answer (or add a comment, and someone with >100 rep will add it to the CW answer), and include a brief description of what differentiates it from others and how it can be used (GUI drawing tool which generates code, type in raw text, or generates image for inclusion in document). We'll eventually sort these answers under headings. |
Assume the following variables: BreathingTestResult - continuous variable indicating how well a person is breathing Gender - binary variable with gender BMI - continuous body mass index FluStatus - whether a person had the flu (positive by test) LastTestDate - days since last text exam, only valid if the patient had a positive flu test and indicates the period from when the person had the flu Can you do the following: lm(BreathingTestResult ~ Gender + BMI + FluStatus + FluStatus:LastTestDate, data = data) If I understand correctly, the FluStatus:LastTestDate term should only be calculated for when FluStatus is true and shouldn't be used in the case of FluStatus = False, however somehow there are estimates calculated for both false and true. Is there a way to do this correctly? Would appreciate any guidance on this! | Consider a statistical problem where you have a response variable that you want to describe conditional on an explanatory variable and a nested variable, where the nested variable only arises as a meaningful variable for particular values of the explanatory variable. In cases where the explanatory variable does not admit a meaningful nested variable, the latter is usually coded either as NA in the data set, or if it is coded with a value, that value is merely a placeholder that does not have any meaningful interpretation. This situation tends to arise whenever you have an explanatory variable indicating the existence of a thing, and one or more nested variables describing the characteristics of that thing. Some examples of this kind of situation in statistical problems are the following: The explanatory variable is an indicator of whether a survey participant is married, and the nested variable is some characteristic of the spouse (e.g., education, age, etc.); The explanatory variable is an indicator of the presence of an item in a space, and the nested variable is a measure of some characteristic of the item (e.g., size, distance, etc.); The explanatory variable is an indicator of the occurrence of an event and the nested variable is a description of some characteristic of the event (e.g., duration, magnitude, etc.). In these kinds of situations, we often want to build a regression-type model (in the broad sense that includes GLMs, GLMMs, etc.) describing the relationship between the response variable and the other variables. It is not obvious how to deal with the nested variable in this type of model. Question: How do we deal with the nested variable in this type of model? Note: This question is designed to give a generalised answer to a recurring question on regarding nested variables in regression (see e.g., , , and ). This question is designed to give a generalised context-independent example of this problem. |
I tried to fix the footer at the bottom of the page, but it didn't work. so guys, can you please help me? note: you can find footer.css file in a folder called page_parameter_mon_ecole and thanks in advance :) ↓↓↓↓↓↓↓↓↓↓ | I have a simple 2-column layout with a footer that clears both the right and left div in my markup. My problem is that I can't get the footer to stay at the bottom of the page in all browsers. It works if the content pushes the footer down, but that's not always the case. |
Is there a way to reduce the size of the spines poking out of bezier curves? Or is there a way to generate smaller bezier curves with smaller spines? | In this example I use Nurbs curves to create shoe laces and it becomes quite hard to operate curves in the regions of loops and knots because of the curves' tilt/scale guides (not sure how to call them). I would really like to hide these guides when I edit curves. Is it possible? |
Not sure how to find the remainder. Any help would be much appreciated. Thanks Checked out the solution for $\frac{2^{2014}}{7}$ but, I wasn't 100% sure of the actual working for finding the remainder of such equations. Therefore requested help for a different value so that i could perhaps know how the whole process worked for a different value. | Find the remainder of $\dfrac{2^{2014}}{7}$ I am new to the modular arithmetic, Any suggestions to solve this question? |
I'm having trouble changing the font of (sub)section titles in my document, I'd like it to be the same as the font used for the main text but as of now, a sans serif font is used for titles and a serif font for the text. I have found some answers here regarding title fonts but they did not work on my document (I suppose because I am using the scrreprt class?). Any help would be much appreciated, especially a solution which a beginner like me can use because I don't have much experience and had difficulties implementing some solutions I read about. Thank you! So far, my document looks like this: \documentclass[a4paper,11pt]{scrreprt} \usepackage[utf8]{inputenc} \usepackage[ngerman]{babel} \usepackage[T1]{fontenc} \graphicspath{{img/}} \usepackage{fancyhdr} \usepackage{lmodern} \usepackage[T1]{fontenc} \usepackage{caption} \usepackage{textcomp} \addtokomafont{section}{\small} \addtokomafont{subsection}{\small} \addtokomafont{subsubsection}{\small} %\usepackage{fontspec} %\setmainfont{Avenir Light} %tried this to use sans serif font in text but it only worked in Luatex and that caused some other formatting issues | How to change the default KOMA-Script font that is used for chapter/section headings etc. to the Computer Modern font that is used in text body? |
I want to change jQuery Datepicker to German Calendar, but it did not work. -I tried that : <script> $( function() { $( "#datepicker" ).datepicker( $.datepicker.regional[ "de" ] ); $( "#locale" ).on( "change", function() { $( "#datepicker" ).datepicker( "option", $.datepicker.regional[ $( this ).val() ] ); }); } ); </script> Thank you! | I really need a localized dropdown calendar. An English calendar doesn't exactly communicate excellence on a Norwegian website ;-) I have experimented with the , their website says it can be localized, however that doesn't seem to work. I am using ASPNET.MVC, and I really want to stick to one javascript library. In this case jQuery. The ajax toolkit calendar would be acceptable, if only it too would display Norwegian names. Update: Awesome! I see I am missing the language files, a not so minor detail :-) |
Is there a places menu in Unity, similar to the one in the old gnome interface? I really liked having such quick access to remote shares. | I'd like to know if it's possible to put a "Places" tab in the upper menu of Ubuntu, such as CentOS, Debian, etc. Thanks |
I need to prove/show that $n^3 \leq 3^n$ for all natural numbers $n$ by strong induction. I have no clue where to begin!!!! :( I know how to do the beginning steps of showing that it's true for $k = 0$ and $k = 1$, etc but get suck on how to start the strong inductive step. | Prove by mathematical induction that: $$\forall n \in \mathbb{N}: 3^{n} > n^{3}$$ Step 1: Show that the statement is true for $n = 1$: $$3^{1} > 1^{3} \Rightarrow 3 > 1$$ Step 2: Show that if the statement is true for $n = p$, it is true for $n = p + 1$ The general idea I had was to start with $(p+1)^{3}$ and during the process substitute in $3^{p}$ for $p^{3}$ as an inequality. $$(p+1)^{3} = p^{3} + 3p^{2} + 3p + 1 < 3^{p} + 3p^{2} + 3p + 1$$ Now, if it can be shown that: $$\forall p \in \mathbb{N}: 3p^{2} + 3p + 1 \leq 2 \cdot 3^{p}$$ ...the proof is complete. This is because $3^{p+1} = 3 \cdot 3^{p}$ and one of those three have already been used. We do this by mathematical induction. First, the base case of $n = 1$: $$3\cdot 1^{2} + 3 \cdot 1 + 1 \not \leq 2 \cdot 3^{1}$$ ..which turns out to be false. What are some more productive approaches to this step? |
I know if you have a Strength of 10 and find the Strength Bobblehead you can get to 11, but what if I find the Bobblehead earlier. Say I find it when my Strength is 9. Do I have Strength 10 or Strength 9+1? Basically, should I wait to go searching for Bobbleheads until I've maxed out a stat, or will I be able to get them all to 11 eventually regardless of when I find the Bobbleheads? | I've been hearing some rumors from friends, mostly anecdotal indicating that skills, when gone past 10 (such as initially having 10 in one skill, then finding a bobblehead or skillbook), actually improve past 10. I can't find any proof of this yet, and my current character right now is slightly incapable of maxing any stats soon to 10 and testing it out. So I'd like to understand if SPECIAL stats increased past 10 show any benefit? Can SPECIAL stats be increased past 10? |
Suppose $\{a_n\}$, $\{b_n\}$ are sequences in $\mathbb R$. Suppose $a_n\geq b_n$ and $\{b_n\}$ converges to $b$. Can we conclude that $\liminf a_n\geq b$. What if we further assume $\{a_n\}$ is bounded below? | Can anyone prove this question? I tried but I didn't get any I idea, so I hope someone can solve it. Let $X_n\leq Y_n$ for each $n\in \Bbb N$. Show that $\liminf X_n \leq \liminf Y_n$ and $\limsup X_n \leq \limsup Y_n$. Please prove this question - thanks. The definition I have: Let $X_n$ be a sequence in real number and let $$E=\{x\in \Bbb R^\sharp:(X_{n_k}) \rightarrow x \text{ for some subsequence }(X_{n_k})\text{ of }(X_n)\}$$ for all $n \in \Bbb N$ and $k$ from $1$ to $\infty$. Then by definition $\lim\sup X_n = \sup E$ and $\lim\inf X_n = \inf E$. |
Is the mass increment with an increase absolute velocity of a body, a direct consequence of energy to mass conversion | I learned recently that when an object moves with a velocity comparable to the velocity of light the (relativistic) mass changes. How does this alteration take place? |
My computer specs are Asus M4A88T-M Antec BP550 Plus 550W G.SKILL Ripjaws Series 8GB (2 x 4GB) 240-Pin DDR3 SD-RAM DDR3 1600 (PC3 12800) RAM Nvidia 550ti 1gb 192bit video card Anthon 2 3.2ghz x3 CPU am3 My computer seems alright but when I play games they will flicker white across the screen and some games will even crash immediately after starting it. I only have this problem with games that require high graphics settings. I noticed the white flicker in games like Minecraft but it's barely noticeable so it's not a problem. The white flickering started randomly while I was playing. I've switched out every part of my PC except for the motherboard and processor. I've re-downloaded and re-installed Windows 3 times with different CDs, downloaded all the drivers and tried old and new ones that I could find. It is still flickering. What can be causing this white flashing? | Alright my computer when i play games will flicker white across the screen and some games will even crash immediately after getting in the game, I only have the problem with games that require high graphics, I notice the white flicker in games like Minecraft but its barely noticeable so its not a problem, the white flickering started randomly while I was playing. I've switched out every part of my pc except for the motherboard and Processor. I've redownloaded windows 3 times with different CD's, I've downloaded all the drivers and tried old and new ones with many parts that I could download drivers on. My computer specs; Asus M4a88t-m motherboard Antec BP550 Plus 550W G.SKILL Ripjaws Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) RAM Nividia 550ti 1gb 192bit video card Anthon 2 3.2ghz x3 CPU am3 |
I've seen a proof that shows that rational numbers are not the same infinity as real numbers. I'm curious if there is a proof that shows $\mathbb{R}^1$ and $\mathbb{R}^2$ are the same infinity. If so, is there a way to map from one to the other for all points? | Could any one give an example of a bijective map from $\mathbb{R}^3\rightarrow \mathbb{R}$? Thank you. |
My lan connection is not working after my ubuntu 14.04 asked for routine upgrades of software. Kindly help | While upgrading today, something caused my wireless network manager to disappear. Not even connecting via wired connection. This error is being shown by files: **(nm-applet:2716): WARNING **: Could not initialize NMClient /org/freedesktop/NetworkManager: The name org.freedesktop.NetworkManager was not provided by any .service files (nm-applet:2716): nm-applet-WARNING **: Error connecting to ModemManager: Error calling StartServiceByName for org.freedesktop.ModemManager1: GDBus.Error:org.freedesktop.DBus.Error.Spawn.ExecFailed: Cannot launch daemon, file not found or permissions invalid (nm-applet:2716): nm-applet-WARNING **: Could not find ShellVersion property on org.gnome.Shell after 5 tries (nm-applet:2716): nm-applet-WARNING **: Failed to register as an agent: (2) The name org.freedesktop.NetworkManager was not provided by any .service files Is there a patch I can download through windows and send through to my ubuntu, or is it a case of having to reload everything? I tried running two versions back but still no internet access. |
I am new to Linux and want to restart Ubuntu. Is there a way that I can erase everything, but still keep ubuntu? Somewhat like a factory reset. | I was playing around with some settings, and now I need to reset GNOME to it's defaults - how do I do that? |
If the input: int[] nums= [1,2,3], target=4; why the output res=0; the res has not been accumulated? public int combinationSum4(int[] nums, int target) { int res=0; helper(nums,target,res); return res; } private void helper(int[] nums, int target, int res){ if (target==0) { res++; return; } else if (target<0) return; else { for(int i=0;i<nums.length;i++){ helper(nums, target-nums[i],res); } } } | I always thought Java uses pass-by-reference. However, I've seen a couple of blog posts (for example, ) that claim that it isn't (the blog post says that Java uses pass-by-value). I don't think I understand the distinction they're making. What is the explanation? |
Hi is there any importers for blender 2.79 for importing JSON files? I have found an importer for 2.50 but this doesn't work for 2.79 nor does it work for 2.50 as after installing the addon on blender 2.57 it doesn't let you enable the addon and will not let you check the enable box. It's also a bit strange that blend4web doesn't have an importer as it has an exporter for json... Thanks in advance! | I need to find a way to import some .json models into Blender, and it seems I can't just import them the same way I can import a .obj model. So is there some way to convert a .json model to a .obj model, or another file type Blender can import? I've tried using Blockbench for this, but I think it only works with Minecraft recourse pack .json models, as those are the only models that will ever actually load in it. Thank you to anyone who can help me figure this out. |
When we prove something, we use mathematical symbol ∀ to stand for "for all." Does it make any difference if we use same symbol for "for any."? | In a textbook (on economics, not "pure" mathematics), one definition requires that some condition holds for any $x,\ x' \in X$, and right afterwards another one requires that some other condition holds for all $x,\ x' \in X$. My question: is there a difference between the two (for any, for all)? Though searching for previous questions returns thousands of results for the query "for any" "for all", I couldn't find this specific one. Sorry if I missed it. |
For example I am converting from ECEF to lla using def ecef_to_lla(x, y, z): lla = pyproj.Proj(proj='latlong', ellps='WGS84', datum='WGS84') ecef = pyproj.Proj(proj='geocent', ellps='WGS84', datum='WGS84') lon, lat, alt = pyproj.transform(ecef, lla, x, y, z) return lon, lat, alt I'm not sure how the ellps and datum keywords differ. Documentation points me here: but it's still unclear how they differ? I though a datum was a model of earth, usually an elippsoid with different parameters. So what's the difference between a datum and ellps? | Are the datum and the ellipsoid the same? What is a Datum? The Earth is shaped like a flattened sphere. This shape is called an ellipsoid. A datum is a model of the earth that is used in mapping. The datum consists of a series of numbers that define the shape and size of the ellipsoid and it's orientation in space. A datum is chosen to give the best possible fit to the true shape of the Earth. in this article.... |
Skype is not installing in my Ubuntu. sudo apt-get install skype giving following output. Reading package lists... Done Building dependency tree Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: skype : Depends: ia32-libs (>= 20080808) but it is not going to be installed W: Duplicate sources.list entry http://archive.canonical.com/ubuntu/ maverick/partner amd64 Packages (/var/lib/apt/lists/archive.canonical.com_ubuntu_dists_maverick_partner_binary-amd64_Packages) W: You may want to run apt-get update to correct these problems E: Unable to correct problems, you have held broken packages. please help | I don't usually post on such forums, but I finally gave up on figuring out what's going on here and I need some help. I need to install Adobe Reader. I am running Ubuntu 12.04 Precise x64 on Intel Core 2 Duo: $ uname -a Linux Edison 3.2.0-26-generic #41-Ubuntu SMP Thu Jun 14 17:49:24 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux I get the following error by attempting to "sudo apt-get install acroread": The following packages have unmet dependencies: acroread : Depends: ia32-libs (>= 20080808) but it is not going to be installed Depends: nspluginwrapper but it is not going to be installed E: Unable to correct problems, you have held broken packages. If I try to install "sudo apt-get install ia32-libs", I get: The following packages have unmet dependencies: ia32-libs : Depends: ia32-libs-multiarch E: Unable to correct problems, you have held broken packages. Finally, if I try to install "sudo apt-get install ia32-libs-multiarch", I get: ia32-libs-multiarch:i386 : Depends: bluez-alsa:i386 but it is not going to be installed Depends: libgettextpo0:i386 but it is not going to be installed Depends: gstreamer0.10-plugins-base:i386 but it is not going to be installed Depends: gstreamer0.10-plugins-good:i386 but it is not going to be installed Depends: gtk2-engines:i386 but it is not going to be installed . . . Does anyone have any idea what's going on? |
When I turn on iMac (iMac Intel 21.5" EMC 2428, Model A1311 / Mid 2011) I get the chime and after some time, a blinking question mark inside a folder icon appears. I have tried all combination keys on mac wireless keyboard and Windows USB Keyboard but nothing worked. Then I replaced hard drive for brand new SSD but that didn't change anything. What else I have tried: 1) All combination keys I could think of. On original mac wireless keyboard and Windows USB keyboard. D, N, T, Option, Command + R, Option + Command + P + R, Shift, Command + S, Command + V Whatever combination I use, doesn't make any impact on the boot process and a question mark appears after while. 2) I plug USB Stick with a bootable system and also System on CD but none of the combination keys worked. I'm unable to eject CD using the Eject button on the keyboard. I can only eject using the mouse while starting. 3) I have replaced batteries on the keyboard and when I turn on with side power button I can see a green LED briefly turn on. Caps lock LED doesn't work but I don't remember this working ever. 4) I have removed all but one RAM carrier. I spent the last few days researching the problem but all point to faulty HDD which I already replaced. What could be a problem? Anything else I could try? | Today i format my "OS X El capitan" partition for installing "Yosemite". But due an error in bootable yosemite usb it didn't install on this partition. After some hours when i turned on iMac and hold down "option" key for boot into usb but just blank screen and mouse show. And every time when i turend on iMac it only show flashing folder with question mark. I've tried to resolve it by reseting "NVRAM". But after restarting problem still same. Also I've tried many "Startup key combinations for Mac" but didn't work any combination on startup. Also i have important data in my other one partition. Please can anyone tell me what i do for resolving that issue Without loosing my data? |
The definition of positive definite function is something like: for all nonzero $x\in R^n$ then the quadratic function $V(x)=x^TPx>0$ where $P \in R^n$x$R^n$ is a positive-definite matrix. for example when I am studing the vector $x=[x_1,x_2]^T$ , the quadratice chosen function $V=0.5(x_1^2+x_2^2)>0$ is a positive definite function. But in one textbook I have found that for a system with three state, i.e $x\in R^3$ for example $x=[x_1,x_2,x_3]^T$ if we choose the quadratic function as : $V=0.5(x_1^2+x_2^2)$ then this chosen function is positive semi-definite in $R^3$. I can't understand why the last function is positive semi-definite in $R^3$ and not positive definite? I thought that because it has been taken only two states i.e $x_1,x_2$ and it has been dropped $x_3$. But I didn't understand the idea of that. | I am confused about the difference between positive semi-definite and positive definite. May I understand that positive semi-definite means symmetric and $x'Ax \ge 0$, while positive definite means symmetric and $x'Ax \gt 0$? |
I am using lyx. I am not sure why my tables looks like this The "Table 1" is much smaller compared to my caption and table content. I set the normal size to 10 pt in lyx, and use large in caption and contents. I am not sure how to change the "table 1" into large in lyx. The only preamble I am using is geometry. The document class is elsevier. | My question is about changing the font size. I have to insert two figures side by side. Coming to inserting the captions for the figures individually: Figure 3: blah blah.....................Figure 4: blah blah... I am able to change the font size of "blah blah". What I want to know is how to change the font size of "Figure 3" or "Figure 4", say the figure headers or something. I do not know what they are called to search on-line. |
In the minor illusion spell it defines it's image object must be [...] no larger than a 5-foot cube. This can potentially be interpreted in two ways: 125 cubed feet of object (must have a volume strictly less or equal to 5ft x 5ft x 5ft) No larger than 5ft in any dimension (must fit in a 5ft cube without any transformation) Which is correct? As a potential counter example to #2 being the relevant definition, the Teleport spell has the specific restriction that [...] If you target an object, it must be able to fit enlirely inside a 10 foot cube [...] which is a very different phrasing to [...] is no larger than a 5-foot cube [...] | In follow up to my question , I would like to find out whether this portion implies shapability and what restrictions are placed on shapeability. And can the same logic be applied to a possibly game breaking point? Choose a door, a window, or an area within range that is no larger than a 20 foot cube It seems that this language implies shapability because the wording is "an area". But does no larger than a 20 foot cube mean no measurement can be larger than 20 feet? Or does it mean the area or volume cannot exceed that of a 20 foot cube? We already know the size can be round or rectangular (windows can be either). |
I and my husband are traveling to Italy, Switzerland and Netherlands in June. Our period of stay in Italy and Switzerland is almost the same, with 5N/6D in Switzerland and 6N/7D in Italy. Unfortunately, we are not able to find an appointment date at Italy consulate in SFO before our departure. Our flight and hotel reservations are done. We are wondering if we can take up visa appointment at Swiss consulate in SFO. If not, what are the chances of getting an emergency/expedited appointment at Italy consulate within 20 days of departure. Please help us here and let us know if it's possible to do so. Any suggestions would be appreciated. TIA | My purpose of travel is to attend an academic conference at Amsterdam. I'm also planning to visit Paris before attending the conference. So, my first port of entry is Paris. Where should I apply for my Schengen visa? I want to apply at the French embassy as the processing time is fast. Is this fine? |
Why is this the case? If I remove the local variable within the for loop scope, it will print task 10 for all tasks, instead of 1-10. class Program { public static void DoWork(int i) { Console.WriteLine("Task {0} starting", i); Thread.Sleep(2000); Console.WriteLine("Task {0} finished", i); } static void Main(string[] args) { Task[] Tasks = new Task[10]; for (int i = 0; i < 10; i++) { int taskNum = i; // make a local copy of the loop counter so // that correct task number is passed into // the lambda expression Tasks[i] = Task.Run(() => DoWork(taskNum)); } Task.WaitAll(Tasks); Console.WriteLine("Finished processing. Press a key to end."); Console.ReadKey(); } } | In the two following snippets, is the first one safe or must you do the second one? By safe I mean is each thread guaranteed to call the method on the Foo from the same loop iteration in which the thread was created? Or must you copy the reference to a new variable "local" to each iteration of the loop? var threads = new List<Thread>(); foreach (Foo f in ListOfFoo) { Thread thread = new Thread(() => f.DoSomething()); threads.Add(thread); thread.Start(); } - var threads = new List<Thread>(); foreach (Foo f in ListOfFoo) { Foo f2 = f; Thread thread = new Thread(() => f2.DoSomething()); threads.Add(thread); thread.Start(); } Update: As pointed out in Jon Skeet's answer, this doesn't have anything specifically to do with threading. |
I have this pattern: dir1/dir2/.log.gz dir1/dir2/a.log.gz dir1/dir2/a.py dir1/dir2/*.gzip.tar I want to get filename or path and extension. e.g: (name,extension)=(dir1/dir2/,.log.gz) (name,extension)=(dir1/dir2/a,.log.gz) (name,extension)=(dir1/dir2/a,.py) (name,extension)=(dir1/dir2/,.gzip.tar) I try: re.findall(r'(.*).*\.?(.*)',path) but it doesn't work perfect | Is there a function to extract the extension from a filename? |
I came across this in proving that the $\sqrt{3}$ is irrational | This is a problem from "" (specifically, exercise set 2 #9), which is one of my math texts. Please note that this isn't homework, but I would still appreciate hints rather than a complete answer. The problem reads as follows: If 3p2 = q2, where $p,q \in \mathbb{Z}$, show that 3 is a common divisor of p and q. I am able to show that 3 divides q, simply by rearranging for p2 and showing that $$p^2 \in \mathbb{Z} \Rightarrow q^2/3 \in \mathbb{Z} \Rightarrow 3|q$$ However, I'm not sure how to show that 3 divides p. Edit: Moron left a comment below in which I was prompted to apply the solution to this question as a proof of $\sqrt{3}$'s irrationality. Here's what I came up with... [incorrect solution...] ...is this correct? Edit: The correct solution is provided in the comments below by Bill Dubuque. |
As title goes, without assuming continuum hypothesis, is there a subset of $\mathbb{R}$ with positive measure but not being continuum? That is, Does there exist $A\subseteq \mathbb{R}$ such that $\mu(A)>0$ and $\aleph_0<|A|<2^{\aleph_0}$? I believe that maybe in some system without assuming continuum hypothesis, there exists. And by the regularity of Lebesgue measure, it suffices to deal with compact set. | Let $X\subset \mathbb{R}$ Lebesgue measurable, $|X|<2^{\aleph_0}$, is it true that $X$ is null? Of course I am not assuming the Continuum Hypothesis. EDIT: It might be helpful to know that all Borel measurable sets have cardinality either $\aleph_0$ or $2^{\aleph_0}$. Then a measurable set of cardinality strictly between those two must be Lebesgue but not Borel measurable. |
How to prove $$\lim_{n \rightarrow \infty}\sqrt[n]{n}=1.$$ I have problem in proving this statement at the beginning my textbook says: Suppose $f_{n}=\sqrt[n]{n}=1+h_{n}$ where does this $1+h_{n}$ come from? and what does it mean? if we can write $\sqrt[n]{n}=1+h_{n}$ then $f_{n}=1+h_{n}$ so by defintion of convergence let $\varepsilon\gt0$ be given. There exists a positive integer $K\gt\frac{1}{h_{n}}$ such that $|f_{n}-l|\lt\varepsilon \implies |1+h_{n}-1|\lt\varepsilon\implies h_{n}\lt\varepsilon$...therefore $\sqrt[n]{n}\to 1$....Am i right? | Possible Duplicate: I know that $$\lim_{n\rightarrow\infty}\sqrt[n]n=1$$ and I can imagine that $n$ grows linearly while $n$th root compresses it exponentially and therefore the result is $1$, but how do I calculate it? |
I am travelling from India with the following itinerary: India -> Germany (April 1, 2018- April 21, 2018) = 21 days Germany -> USA (April 21, 2018- June 30, 2018) = 39 days [not Schengen - I already have a 10 year US visa] USA -> Italy (July 1, 2018- July 15, 2018) = 15 days Italy -> Croatia (July 15, 2018- July 17, 2018) = 3 days [not Schengen - but requires a multiple-entry Schengen visa] Croatia -> Germany (July 18, 2018 - July 20, 2018) = 3 days Germany -> India (July 20, 2018) I can see I will need a multiple-entry Schengen visa valid for at least 6 months or so. But I'm confused what the number of days permitted for my "Duration of Stay" in Schengen will be. i.e. What should I seek in duration of stay? Will they grant 90 days or an exact number of days? | I have submitted a Schengen visa application, where my duration of intended stay is 7 days. Now, what could be my duration of visa validity 7 days or 90 days? |
A simple code like this: \documentclass[12pt,a4paper]{article} \usepackage{hyperref} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \begin{document} the first page \clearpage the second page \label{key} \clearpage I want to returen to page \pageref{key}, but return to page 1 when clicking the typeset number "2". \end{document} why does the \pageref workt wrong? | In the following code, the command \label{my} appears on page 4, as well \pageref{my} says "4", but the hyperlink points to the page one. Why is that? \documentclass{book} \usepackage{hyperref} \usepackage{lipsum} \begin{document} % Four pages of text. \lipsum[1-20] % The label is on fourth page. \label{my} % Buggy pageref. It produces the number 4, but the link leads to the first page. \pageref{my} \end{document} |
I posted my meta profile link in chat and my image got defected this is how its looks in my profile as you can see I want that butterfly back :) | In chat certain users image is not showing correctly but when we change 16 to 18 in image src it just works fine please let me know if its dup i tried but couldn't find |
Let's just assume that one flags an answer, and that flag, barring any changes to the original post would be deemed helpful. Now, if the flag is still active and the poster changes their answer to something that is no longer inappropriate, will the flag still be marked as helpful? | Now that it is more transparent how the flagging system works from the flagger's perspective (e.g. we have a flag reputation and stats based on our flagging history) it seems important that the system is fair. With that in mind, what happens when I flag something and then that something gets edited or corrected after-the-fact? Does my flag go away? (This could be abused by trolls) Do I get penalized for an invalid flag even though my original flag was correct? Do I still get credit if their correction doesn't fix the problem? |
I'd like to know how to prove algebraic numbers form a field, i.e., if $a,b$ are algebraic numbers, prove that $ab$ and $a+b$ are also algebraic numbers by finding specific polynomials that satisfy $ab$ and $a+b$. I know there is a way to do this using Kronecker Symbol, but not sure exactly how to do it. Edit: This question is different from the suggested duplicated one in that this question asks for answer to prove that algebraic numbers form a field in unconventional ways such as using Kronecker Symbol. As the result, answers are very different from the one suggested duplicated. So this question deserves remaining open. | Suppose $E/F$ is a field extension and $\alpha, \beta \in E$ are algebraic over $F$. Then it is not too hard to see that when $\alpha$ is nonzero, $1/\alpha$ is also algebraic. If $a_0 + a_1\alpha + \cdots + a_n \alpha^n = 0$, then dividing by $\alpha^{n}$ gives $$a_0\frac{1}{\alpha^n} + a_1\frac{1}{\alpha^{n-1}} + \cdots + a_n = 0.$$ Is there a similar elementary way to show that $\alpha + \beta$ and $\alpha \beta$ are also algebraic (i.e. finding an explicit formula for a polynomial that has $\alpha + \beta$ or $\alpha\beta$ as its root)? The only proof I know for this fact is the one where you show that $F(\alpha, \beta) / F$ is a finite field extension and thus an algebraic extension. |
Let $M$ be a maximum subgroup of $G,$ that is, a proper subgroup of $G$ such that the only subgroups of $G$ that contain $M$ are $M$ and $G.$ It shows that if $M\underline{\lhd}G$ then $[G:M]$ is finite and prime. | I'm having trouble with an exercise in "Introduce to the theory of group" book. This is problem: Let $M$ be a maximal subgroup of $G$. Prove that if $M$ is a normal subgroup of $G$, then $[G: M]$ is finite and equal to a prime. |
I'm trying to make this sample working but it fails every time and displays the bad response. Can you please explain to me why that is the case? Thanks DECLARE @CARACS NVARCHAR(max) = 'DLV, DLC' SELECT CASE WHEN 'DLV' IN (@CARACS) THEN 'GOOD' ELSE 'BAD' END | How do I parameterize a query containing an IN clause with a variable number of arguments, like this one? SELECT * FROM Tags WHERE Name IN ('ruby','rails','scruffy','rubyonrails') ORDER BY Count DESC In this query, the number of arguments could be anywhere from 1 to 5. I would prefer not to use a dedicated stored procedure for this (or XML), but if there is some elegant way specific to , I am open to that. |
I have a Lenovo T480s that I connect to my dock at work every day. Today all of a sudden my monitors remain black after I'm prompted for the encryption key for my disk. Usually, the login prompt should turn up. Booting my machine without the dock works fine. Any ideas to how I can fix this? Any help is appreciated. | I performed the most recent kernel update on my Dell 5290 2-in-1 earlier today. But moments after I plug it into its docking station, the screen flickers, blanks and freezes. The only item left on the screen is the mouse pointer, and it is stuck. If I leave the tablet not plugged in, it runs just fine. It seems to be the docking station that triggers the freeze. That said, I can log into the tablet via ssh even with the screen frozen. So the system is still running. But if I try to reboot the tablet via the reboot command, nothing appears to happen. sudo reboot -f will reboot the system, while sudo reboot will not. Any ideas where I should start looking to identify this problem? |
I am going to be a high school freshman next year and I have acquired a strong interest in physics. I have a mathematical background, upto, but not including, Calculus. I am looking for in depth resources covering classic mechanics enough to move onto more in depth texts on relativity as well as quantum theory. Again, I have a strong math background to all the work leading up to Calculus, and I will be taking Calculus next school year. | I'm a bachelor student majoring in math, and pretty interested in physics. I would like a book to study for classical mechanics, that will prepare me to work through . What books would be good for a beginner? |
After updating Mountain Lion to Mavericks xQuartz and MacPorts throws errors about insufficient permissions. (xQuartz and MacPorts are the latest version) I noticed: $ sudo mkdir /opt/tmp mkdir: /opt/tmp: Permission denied I am on Administrator Account. sudo port install htop Error: Insufficient privileges to write to MacPorts install prefix. I can't even uninstall MacPorts with the command from %% sudo rm -rf \ /opt/local \ /Applications/DarwinPorts \ /Applications/MacPorts \ /Library/LaunchDaemons/org.macports.* \ /Library/Receipts/DarwinPorts*.pkg \ /Library/Receipts/MacPorts*.pkg \ /Library/StartupItems/DarwinPortsStartup \ /Library/Tcl/darwinports1.0 \ /Library/Tcl/macports1.0 \ ~/.macports | I try to install MacPorts and get this $ sudo make install make: getcwd: Permission denied shell-init: error retrieving current directory: getcwd: cannot access parent directories: Permission denied ===> making install in doc job-working-directory: error retrieving current directory: getcwd: cannot access parent directories: Permission denied chdir: error retrieving current directory: getcwd: cannot access parent directories: Permission denied make: getcwd: Permission denied /usr/bin/install -c -d -o root -g admin -m 0755 "/opt/local" shell-init: error retrieving current directory: getcwd: cannot access parent directories: Permission denied install: mkdir /opt: Permission denied make[1]: *** [install] Error 71 make: *** [install] Error 1 I am also not able to $ sudo mkdir /opt mkdir: /opt: Permission denied I can create the directory with open / and then with Finder. I am also able to install MacPorts with the installer .pgk, but then: sudo port install htop Error: Insufficient privileges to write to MacPorts install prefix. |
I filled out a form early November to get a Swiss visa (applying in Singapore but not Singaporean) with my travel dates as 19.12.2017 to 02.01.2018. The first available appointment was on the 1st of December and I took it. During the time in between, my travel dates changed to one week later (both arrival and departure). Now, my travel itinerary and supporting documents all have different dates from the dates on the form. What do I do? I can fill out a new form with the right dates without paying any fees but the online ID on that form will be different. As mentioned in the comments, I haven't got my visa yet - the interview is tomorrow. | I am an Indian student in the UK. If I already had a single entry Schengen visa and I apply again to the French embassy, will I be issued with multiple-entry? If I get the visa, but due to a problem, I cannot travel on the intended dates(ones I mentioned on visa form) and decide to travel a month later, will it cause a problem when I travel next. And if I dont exactly follow the itenary that I submitted with my visa application? As far as dates are concerned. I mean this: Suppose my visa is valid for May-August. When I applied for this visa, my itenary and hotel bookings were for June. But now I decide to travel instead in July. Will there be a problem if I did not take the journey for which I initially applied the visa and take a different journey later instead |
Upgraded to 20.04. Much software is now snaps. I installed both FreeCAD and GnuCash as snaps from the software center, and neither has created a .desktop launcher that can be found, launched, or added to favorites in GNOME. I know I could make them by hand, but am I doing something wrong? I removed the snaps and installed via apt, and the .desktop launchers are now present. Shouldn't snaps also create .desktop launchers? | I installed regular gnome-software to be able to install Flatpaks as well. Right after I did that, all was fine: I could see both "Software" and "Ubuntu software" in the launcher overview and launch either of them. However, after a restart, I could no longer see Ubuntu Software, and installed Snaps weren't present in the menu anymore either. I have since uninstalled gnome-software, un- and re-installed both Ubuntu Software (snap remove snap-store and snap install snap-store) and the Snap app I'm testing with, and restarted, but I still can't see them. Why did that happen? As requested by pomsky: $ ls /var/lib/snapd/desktop/applications/ chromium_chromium.desktop gnome-system-monitor_gnome-system-monitor.desktop keepassxc_keepassxc.desktop mimeinfo.cache signal-desktop_signal-desktop.desktop skype_skypeforlinux.desktop snap-store_snap-store.desktop spotify_spotify.desktop ubports-installer_ubports-installer.desktop and $ echo $XDG_DATA_DIRS /home/vincent/.local/share/flatpak/exports/share/:/var/lib/flatpak/exports/share/:/usr/local/share/:/usr/share/ |
I graduated from my undergraduate program two years ago with a major in Computer Science. During my undergraduate studies, I did research with a professor, and published under the university's affiliation; (Department of Computer Science, Uni Name). I am currently working in a company which I will refer to as G. I recently worked on a research idea during my weekends which led to an accepted paper in a conference. I would publish with G as an affiliation, except G has a ridiculous 3 month process to allow an employee to use them as an affiliation in a research paper, while the deadline for modifying personal information in the accepted paper is in a month. My question is, can I add my undergraduate school as my affiliation? The work was in no way or form sponsored by G or my undergraduate school. | Recently my paper is reviewed (by a professor from independent third party) and accepted by a journal. But, my employer allows me to publish this paper only without its name there. Publishing house is expecting affiliation for each author, i.e. I can not leave affiliation as blank. What should I write as the affiliation? |
I want to get a json from a url. As an example I want to get the json of this url: And how do I do this in JavaScript now! | I need to do an request in JavaScript. What's the best way to do that? I need to do this in a Mac OS X dashcode widget. |
Let $A$ be a 4$\times$ 7 real matrix and B be a 7$\times$4 real matrix such that $AB=I_4$, where $I_4$ is the $4 \times 4$ identity matrix.Which of the followings are true? $\DeclareMathOperator{\rank}{rank}$ $\rank(A)=4$ $\rank(B)=7$ nullity$(B)=0$ $BA=I_7$ I know $B$ is a 7$\times$4 matrix ,then its row rank and column rank are same. rank(B) $\leq$ 4. So (2) is false, but I have no idea about others.please help. Thanks. | Let $A$ be a $4 \times 7$ real matrix and $B$ be a $7 \times 4$ real matrix such that $AB=I_4$. Which of the following are true? 1) rank$(A)=4$ 2) rank$(B)=7$ 3) nullity$(B)=0$ 4) $BA=I_7$. My attempt: $4=\operatorname{rank}(AB) \leq \min\{{\operatorname{rank}(A),\operatorname{rank}(B)}\}$. So $\operatorname{rank}(A)$ must be $4$. It shows that 1) is true 2) is false by Dimension theorem How to check 3) and 4) ? |
I was trying to get my NTFS drive to work today and I discovered that the diskutil thinks I have two local hard drive. This phenomenon is not occurred on my Macbook Pro. Do anyone know why? Here is what it shows: | I looked at the details provided in my system report/storage and I noticed that it appears I have a hard drive of 499.05GB and an additional SSD drive of 499.42GB. Does this mean I have 1TB of data? I only have 139GB available so do I have 500GB 'hiding' somewhere? (If so where??) I am unsure how to interpret this information- why does it list both storage types? Is it duplicating the information? Macintosh HD: Available: 139.8 GB (139,800,666,112 bytes) Capacity: 499.05 GB (499,046,809,600 bytes) Mount Point: / File System: Journaled HFS+ Writable: Yes Ignore Ownership: No BSD Name: disk1 Volume UUID: EF0908C8-XXXX-XXXX-XXXX-XXXX80333709 Logical Volume: Revertible: Yes (unlock and decryption required) Encrypted: Yes Encryption Type: AES-XTS Locked: No LV UUID: 8CC9C88D-XXXX-XXXX-XXXX-XXXX2002329B Logical Volume Group: Name: Macintosh HD Size: 499.42 GB (499,418,034,176 bytes) Free Space: 18.9 MB (18,903,040 bytes) LVG UUID: EE040070-XXXX-XXXX-XXXX-XXXXA83B309 Physical Volumes: disk0s2: #is this a second disk? Device Name: APPLE SSD SM0512G Media Name: APPLE SSD SM0512G Media Size: 499.42 GB (499,418,034,176 bytes) Medium Type: SSD Protocol: PCI Internal: Yes Partition Map Type: GPT(GUID Partition Table) #does this mean its partitioned? Status: Online S.M.A.R.T. Status: Verified PV UUID: A1391405-XXXX-XXXX-XXXX-XXX2E8FCDF3 |
I want to develop an application in java to capture video from webcam and store it onto a particular location.Can anyone provide me the working code? What type(usb,ip etc..) of webcam is the best in order to develop the application. Please help me. how to proceed? | How can I continuously capture images from a webcam? I want to experiment with object recognition (by maybe using java media framework). I was thinking of creating two threads one thread: Node 1: capture live image Node 2: save image as "1.jpg" Node 3: wait 5 seconds Node 4: repeat... other thread: Node 1: wait until image is captured Node 2: using the "1.jpg" get colors from every pixle Node 3: save data in arrays Node 4: repeat... |
According to relativity, gravity is not a force, and an item doesn't fall, so much as travel through a straight line (geodesic) through space time which is warped. Because the geodesics converge, it gives the impressions that items fall. This I understand, but I'm having trouble relating this to magnetism. Like gravity, it would make sense that magnetism isn't some magical invisible force that spans space pulling items together, but rather that it is another warpage of space-time. This warpage must be different from gravity. For one, similar polls repel each other (thus the geodesics of similar polls must diverge rather than converge). That's not hard to fathom. But here's where I'm really getting confused. Unlike gravity, magnets only attract certain types of elements (iron, etc), whereas it does not effect things like glass, etc. So the question is why do some types objects respect this 'warpage', whereas others do not? How does charge relate to the geodesics of space-time? | For gravity, we have General Relativity, which is a geometric theory for gravitation. Is there a similar analog for Electromagnetism? |
It would help if there is a way to toggle the underlining on and off programmatically, assigning the command to a button to enable me to toggle with a single click. It is a pain to go through the menus every time I want to do it currently. How do I do this? | What macro could turn ON/OFF some proofing settings? (Unfortunately macro recording doesn't record the setting change) I'm looking for a way to turn ON/OFF 2 proofing settings (at the same time): check spelling as you type mark grammar errors as you type |
I just reinstalled mountain lion and seem to have lost git in the process. I tried following this post : but although I can cd into /usr/local/git I get /usr/bin:/bin:/usr/sbin:/sbin:/usr/local/binwhen I echo $PATH How can I change the path so I can go back to using git? Sorry if this is an obvious question, I'm fairly new to git/terminal commands. Update: I tried as suggested in another post and it seems to be working again: sudo -s mkdir -p /usr/local/bin ln -s /usr/local/git/bin/git /usr/local/bin/git exit | I just upgraded to OS X Lion and now cannot initialize Git where it used to work fine: $ git add . -bash: git: command not found I'm new to Git and to programming, so I'm sure it's a quick fix, any help is greatly appreciated. Thanks guys! |
How can I use a meta query like this: >>>>>> KEY_X Conditional IS ABSOLUTELY REQUIRED <<<<<<<<<< array( 'key' => 'Key_X', 'value' => 'Value_for_X' ), >>>>>> KEY_Y **OR** KEY_Z ARE REQUIRED / AT LEAST ONE <<<<<<<<<< array( 'key' => 'Key_Y', 'value' => 'Value_for_X' ), array( 'key' => 'Key_Z', 'value' => 'Value_for_Z' ) So the first one is an absolute must, and then one or the other is required (at least one). Thank you so much! Ciprian | I'm trying to do some filtering for some posts in WP_Query, but I can't seem to get the right condition. Basically what I wanna do, is get posts that have the custom field event_data (sorted by this field) and among those posts to select only those who have one of these other fields filled in event_doc1, event_doc2, event_doc3, main_doc. The code is below. $metaCondition = array( 'relation' => 'OR', array( 'key' => 'main_doc', 'value' => 0, 'compare' => '!=', 'type' => 'NUMBER' ), array( 'key' => 'event_doc1', 'value' => 0, 'compare' => '!=', 'type' => 'NUMBER' ), array( 'key' => 'event_doc2', 'value' => 0, 'compare' => '!=', 'type' => 'NUMBER' ), array( 'key' => 'event_doc3', 'value' => 0, 'compare' => '!=', 'type' => 'NUMBER' ) ); $query = array( 'numberposts' => 4, 'orderby' => 'meta_value', 'meta_key' => 'event_data', 'order' => 'ASC', 'meta_query' => $metaCondition ); Thanks in advance to everone! |
My computer is less than 6 months old and ever since I got it the power supply sometimes makes a whining noise. Even when the computer is off. It's a 600W ATX Corrsair. Is there anything I can do about it? I've got it plugged into a UPS. | I have many different AC adapters and power supplies for a variety of devices, ranging from small 5V/1A USB chargers to laptop power adapters and desktop PSUs. However, I often hear a whining noise from some of these power supplies. This happens most often when they are not connected to a device or otherwise in use, and stop making noise when I connect a load to it such as by plugging in a device that is not fully charged. Why do some AC adapters and power supplies make this whining noise? Why do some not make this noise? Is there anything I can do to suppress it? |
Let $x_n$ be a sequence of real numbers such that the subsequences subsequences $(x_{2n})$, $(x_{2n+1})$ and $(x_{3n})$ converge. Prove that $x_n$ converge. I want to prove that all the subsequences that converge, converge to the same point. In other words, I want to prove that their limit is the same. (If not, $x_n$ doesn't converge) Though, I don't know how to go about to proving $\lim(x_{2n})=\lim(x_{2n+1})$. | I don't know how to begin this. My thoughts are that since there are three convergent subsequences, we could use some knowledge about their limits to construct our convergent sequence but I'm not sure how to prove $x_n$ also converges. Is there a property of metric spaces I should use, or something about Bolzano-Weierstrass theorem (for metric spaces)? EDIT: As noted in a comment I am not allowed to assume they all converge to the same limit. |
In solid mode my character has all their details and colors on, but when I switch to render, the character goes completely black regardless of the light. How do I fix this? | I don't know why but now, when i go in material preview or rendered (in solid mode it works fine), my object is entirely gray, or invisible idk, because it has the same color of the background. I've been working for days on this project without having this issue, it suddenly showed up. I tried opening other old projects and suddenly they all do the same so i guess it is some blender program setting that applies for all the projects, but idk how it happened cuz i didn't change anything :/, anyone got any tips? |
I am using a script called conv-script that I found on AskUbuntu . It looks like this #!/bin/sh readarray -t files < wma-files.txt for file in "${files[@]}"; do out=${file%.wma}.mp3 probe=`avprobe -show_streams "$file" 2>/dev/null` rate=`echo "$probe" | grep "^bit_rate" | sed "s:.*=\(.*\)[0-9][0-9][0-9][.].*:\1:" | head -1` ffmpeg -i "$file" -ab "$rate"k "$out" && rm "$file" done I have ran sudo chmod +x ./conv-script and then I try and execute it with sudo ./conv-script After doing so I get an error sudo: ./conv-script: command not found I am unsure what I am doing wrong as I can see the file in the current working directory and I have set it to be executable. One thing I thought it might be was the first line of my script is wrong, but I have another script with the same shebang and it executes fine. When I use the shebang in the original #!/usr/bin/env bash I get the same thing. Thanks for the help EDIT: output of file conv-script conv-script: a /usr/bin/env bash script, ASCII text executable output of stat conv-script File: ‘conv-script’ Size: 325 Blocks: 64 IO Block: 32768 regular file Device: 821h/2081d Inode: 82004 Links: 1 Access: (0644/-rw-r--r--) Uid: ( 1000/ kalenpw) Gid: ( 1000/ kalenpw) Access: 2016-05-17 16:40:43.000000000 -0600 Modify: 2016-05-17 14:33:31.000000000 -0600 Change: 2016-05-17 14:33:32.000000000 -0600 Birth: - | I have a script that I need to execute on an NTFS partition. The script's permission is set to 600. I attempted to modify the permissions by running chmod 755 script.sh, which doesn't report a failure or anything - but it also doesn't change the permissions on the file: $ stat script.sh File: `script.sh' Size: 297070 Blocks: 584 IO Block: 4096 regular file Device: 811h/2065d Inode: 35515 Links: 1 Access: (0600/-rw-------) Uid: ( 1000/ xxxxxx) Gid: ( 1000/ xxxxxx) Access: 2010-09-30 14:05:16.041621000 -0700 Modify: 2010-09-30 14:05:05.070157000 -0700 Change: 2010-09-30 14:05:05.070475000 -0700 $ chmod 755 script.sh $ stat script.sh File: `script.sh' Size: 297070 Blocks: 584 IO Block: 4096 regular file Device: 811h/2065d Inode: 35515 Links: 1 Access: (0600/-rw-------) Uid: ( 1000/ xxxxxx) Gid: ( 1000/ xxxxxx) Access: 2010-09-30 14:05:16.041621000 -0700 Modify: 2010-09-30 14:05:05.070157000 -0700 Change: 2010-09-30 14:05:05.070475000 -0700 As you can see, it remains unchanged. |
I've got the error message said "cannot have instance property or field initializers in structs" and wonder if there is any technical reason for this? Why doesn't a compiler behave like an initialization happens in a constructor? | In .NET, a value type (C# struct) can't have a constructor with no parameters. According to this is mandated by the CLI specification. What happens is that for every value-type a default constructor is created (by the compiler?) which initialized all members to zero (or null). Why is it disallowed to define such a default constructor? One trivial use is for rational numbers: public struct Rational { private long numerator; private long denominator; public Rational(long num, long denom) { /* Todo: Find GCD etc. */ } public Rational(long num) { numerator = num; denominator = 1; } public Rational() // This is not allowed { numerator = 0; denominator = 1; } } Using current version of C#, a default Rational is 0/0 which is not so cool. PS: Will default parameters help solve this for C# 4.0 or will the CLR-defined default constructor be called? answered: To use your example, what would you want to happen when someone did: Rational[] fractions = new Rational[1000]; Should it run through your constructor 1000 times? Sure it should, that's why I wrote the default constructor in the first place. The CLR should use the default zeroing constructor when no explicit default constructor is defined; that way you only pay for what you use. Then if I want a container of 1000 non-default Rationals (and want to optimize away the 1000 constructions) I will use a List<Rational> rather than an array. This reason, in my mind, is not strong enough to prevent definition of a default constructor. |
I ve been assigned the following problem: How can we prove by induction that for every $x,y > 0$ and $n \in N$ it is true that: $$\frac{x^n+y^n}{2} \geq \bigg(\frac{x+y}{2}\bigg)^n$$ I have established a base of $n=1$ so that $\frac{x+y}{2} = \frac{x+y}{2}$ and have assumed that the statement is true for any natural $k$ but am having problem proving that it is true for $k+1$. Any help is appreciated! | Can you help me to prove that $$(x+y)^n\leq 2^{n-1}(x^n+y^n)$$ for $n\ge1$ and $x,y\ge0$. I tried by induction, but I didn't get a result. |
If you you will get a list of answers: However, if you then you get a list of questions: Searches tagged is:answer should only return answers. The is:answer flag should take priority, and anything related to the question should be inherited from the parent question (like using question_id field for answers in the ). This way we could, for instance, . This currently returns nothing while will provide us with what we want. | Some users on Stack Overflow have been spending a bit of time that really need to be closed. This is working out very well, I'm hoping we can cut out some noise for them when they execute these types of searches. Suppose we have the query: And we want to refine it so that we only see open questions. Adding closed:0 to that seems like it should filter out questions that have already been closed, but in reality it doesn't because answers can't be closed. This seems easy to fix if closed:[0-1] applies to the parent question when is:answer is toggled. |
For my research I am looking into the relationship between an outcome (Y) and a predictor (X) as follows: $$Y = X + e$$ where $e$ is the error term. Because there might be reverse causality I am employing a 2 stage estimation strategy. My first stage being: $$X = Z + u$$ where $u$ is an error term. Now I was all concerned about the exclusion restriction and came up with a series of robustness checks. Instead the main critique I received concerned reverse causality in the first stage. Of course I looked into this when I started this project and as far as I am aware there is two conditions that should be met for the instrument to be valid: relevance: Z should be correlated with X, or $corr(Z,X)= 0$; exogeneity: Z should not be correlated with unobserved factors influencing Y, or $corr(Z,e)\neq 0$. Am I overlooking something? Or are there recent developments that I am not aware of maybe? Any guidance much appreciated! | The standard scheme of instrumental variable in terms of causality (->) is: Z -> X -> Y Where Z is an instrument, X an endogenous variable, and Y a response. Is it possible, that following relations: Z <- X ->Y Z <-> X ->Y are also valid? While correlation between instrument and variable is satisfied, how may I think of exclusion restriction in such cases? NOTE: The notation <-> is not explicit and might lead to different understandings of the problem. Still, the answers highlight this issue and use it to show important aspects of the problem. When reading, please proceed with caution about this part of the question. |
I've checked questions like: They don't really address my problem. I will be in Montreal for 4 months. I'm looking for a SIM card. Most of the plans I saw are with commitment of at least one year or so. The most important part of the plan is data (for Skype calls and apps for messaging). 3 to 5 GB/month would be perfect. What are the best options I have? | Next month I am traveling to country X, where I would need Y minutes of calls, Z text messages and most importantly Q megabytes of data. How can I find the cheapest/most reliable SIM card for my needs? |
Recently I have been issued a tourism Schengen visa to France valid until end of October. Also I applied for a student visa to Italy for a master's program that starts in September. It seems there will be overlapping weeks between the two visas yet they are of different types (one is type C the other is type D). Would that cause a problem and force me to cancel one visa or the other? | I have an existing used Schengen visa from the 21-July-2015 to 20-July-2016 issued by Belgium. I recently applied for a Schengen visa from Germany & was issued a visa from the 19-July-2016 to 18-July-2017. As you can see, there's an overlap of 19th & 20th of June. Would this cause an issue when I'm traveling? The agents at VFS assured me that this wouldn't be an issue but can someone please confirm? |
I have $23k in student loans and pay $400/mo on them. I have about $2500 left over after my bills each month. I have a 401k and am already contributing the maximum on it. Does it make sense to spend my excess income to reduce my student loan debt to $0 to free up my $400 each month, or should I find some kind of investment to put it in? My wife also has similar student loan debt and I was thinking of tackling hers after mine. From my little understanding of the stock market it doesn't seem like it had been performing too well lately. Looking for advice on how to proceed to utilize my excess income and maximize my returns. Thanks in advance. | I have been reading the top posts here, and the recommendations for what to invest in are often similar. What I'd like to know, in as simply of terms as possible, is what the consensus is on priority of these investments. I am new to this, but here are some of the obvious options: Paying off credit card debt Paying off mortgage / student loans 401k up to employer match 401k past employer match IRA Emergency fund Other important investments that I have missed Clearly this will vary person to person, but if you were asked to put an ordered recommendation on a highway billboard, what would it be? (For example: Pay off credit debt Emergency fund for 6 months 401k up to match ... ) |
Let $M$ be a finitely generated Artinian module over a commutative ring $A$. Why is $A/\mathrm{ann}(M)$ Artinian? | It is easy to show that if $M$ is a Noetherian $R$-module then $R/\mbox{ann}(M)$ is a Noetherian ring. Is there a similar (or dual) result for Artinian modules? |
I try to type correct password. but it say "Sorry Try again" I try to type so long time. But nothing happen. Why? | When I'm about to install a program in the terminal it wants the password: [sudo] password for xxx: But when I start to type my password nothing happens. What should I do? |
For example, how do I find the cheapest tickets from any place in India to any place in either of England, Germany, Netherlands, Spain. Hope the questions makes sense? | Several airline and trip planning sites will allow you to check "I am flexible with my dates" or a similar option. Is there any way to also search more broadly for location? For example, if you wanted to leave from YYZ or YKF and arrive at any airport in California, can a search for such flights be done somehow? I ask because when I plan plane trips, I want the lowest price. I'm OK with leaving a day or two later if I save $200 (same with the return trip). There are 3 airports within 80 km of me, I'll leave from the one with the cheapest flight. And I'm also OK with changing the trip to spend time exploring San Francisco instead of lying on the beach near San Diego, and that sort of thing. Normally this would take dozens of searches, but I'd like to see it all at once. |
Have a look at the bottom of . You can see that the code formatting continues even after the end of the answer. This is because the elements <pre> and <code> are unclosed for some reason, . Note also how the three last lines of the code block are not visible. Here's a picture from my browser (Firefox 28.0): To me, seems fine, so the question is - what is causing this glitch? | Here's the link: If you scroll down to the answer that starts like this... Just showing the answer of Pandincus with "of the shelf" code and some explanation: You need two solutions for this example ( I know it could be done via one also ; ), let the advanced students present it ... So here is the DDL SQL for the table : You'll see that the user/timestamp information for that question is encapsulated in a code block. Edit: Added image in case someone edits the post. |
Is this dependency injection if I change the below code class Needer { Needed obj; AnotherNeeded obj2; public Needer() { obj = new Neede(); obj2 = new AnotherNeede(); } } To this code class Needer { Needed obj; AnotherNeeded obj2; public Needer(Needed param1, AnotherNeeded param2) { obj = param1; obj2 = param2; } } | There have been several questions already posted with specific questions about , such as when to use it and what frameworks are there for it. However, What is dependency injection and when/why should or shouldn't it be used? |
Here the last column is my response variable. I have four predictors that are ordinal. How best to code them to preserve their "ordinal" properties? | I've got some ordinal variables b and a and a categorized variable c. I would like to fit a multinomial logit regression from the library car. I tried to ignore the ordinal scale. I have the following data: a<-c( 3, 4, 4, 4, 3, 4, 3, 3, 4, 2, 2, 4, 3, 3, 3, 1, 3, 2, 2, 3, 3, 1, 3, 2, 2, 3, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 3, 3, 2, 2, 3, 1, 2, 2, 2, 2, 3, 2, 3, 4, 4, 3, 3, 2, 2, 3, 3, 3, 2, 1, 1, 1, 1, 1, 1, 2, 3, 4, 3, 3, 4, 3, 4, 3, 2, 3, 3, 3, 3, 3, 4, 3, 4, 3, 3, 2, 3, 3, 3, 3, 2, 2, 3, 3, 3, 2, 3, 2, 3, 1, 2, 2, 1, 1, 4, 3, 3, 2, 2, 2, 2, 2, 2, 3, 4, 4, 4, 3, 3, 3, 3, 3, 4, 4, 3, 3, 2, 3, 3, 3, 3, 4, 3, 4, 2, 2, 3, 3, 3, 2, 2, 3, 2, 4, 2, 2, 2, 2, 2, 1, 2, 2, 1, 1, 3, 4, 3, 3, 2, 3, 3, 3, 3, 2, 3, 3, 3, 2, 1) c<-c(5 ,3 ,4 ,3 ,4 ,4 ,2 ,2 ,3 ,4 ,2 ,5, 3, 5, 4 ,3 ,2 ,4 ,4 ,4, 4 ,4, 4, 2 ,3, 4 ,2 ,3 ,3 ,3 ,4 ,3 ,3 ,2 ,2 ,3 ,3 ,3 ,3 ,4 ,2 ,4 ,3, 3, 3, 4, 4, 3, 3 ,2 ,3 ,3 ,3 ,3, 4 ,4, 4, 3, 2, 2 ,4 ,4 ,3 ,3 ,2 ,2 ,1 ,2 ,2 ,2 ,1 ,2 ,5 ,2 ,3 ,3 ,2, 4 ,3 ,1 ,2 ,3 ,2 ,3 ,3 ,3 ,3 ,3 ,3 ,2 ,2 ,2 ,2 ,3 ,2 ,4 ,3, 3 ,2 ,3, 2, 4, 3, 3, 3 ,3 ,4 ,2 ,2 ,4 ,3 ,3 ,3 ,3 ,3 ,2 ,3, 3 ,3, 3, 4 ,4 ,4 ,1 ,3 ,3 ,3 ,4 ,4 ,4 ,3 ,2 ,4 ,4 ,2 ,4 ,4 ,4 ,4 ,2 ,3 ,3, 2, 2 ,3 ,2 ,3 ,4 ,5 ,2, 3 ,3 ,2 ,3 ,2 ,2 ,3 ,2 ,2 ,4 ,4 ,3 ,3 ,2, 4 ,4 ,2 ,4 ,3 ,4, 4, 3 ,2 ,3) b<-c(3 ,2, 2, 2, 3, 2, 3, 3, 4, 1, 2, 2, 4, 2, 3, 1, 3, 1, 2, 4, 2, 1, 3, 2, 2, 2, 1, 3, 3, 3, 2, 2, 2, 2, 1, 3, 1, 3, 2, 3, 1 ,3 ,3 ,2, 2, 3, 1, 3, 2, 2, 2, 2, 2, 2, 3, 4, 3, 3, 2, 1, 4, 3 ,3 ,2 ,2, 1, 2, 2, 2, 2, 1, 2, 5, 3, 3, 4, 3, 4, 1, 2, 3, 3, 3, 3, 2, 3, 3, 3, 3, 2, 3, 2, 2, 3, 2 ,4 ,2 ,3 ,2 ,2 ,2 ,4 ,2 ,2 ,2 ,2 ,2 ,2, 1, 5 ,4 ,3 ,2, 2 ,2 ,2 ,2 ,4 ,2 ,2 ,4 ,3 ,3 ,1 ,2 ,2 ,2 ,2 ,2 ,2, 2, 2, 2, 2, 2 ,2 ,2 ,2 ,2 ,2 ,2, 2, 2, 2 ,2 ,2 ,2 ,2 ,5 ,4 ,3 ,2 ,1 ,1 ,1 ,4 ,3 ,2 ,2 ,3 ,3 ,3 ,2 ,2 ,2 ,2 ,2, 3, 2 ,2 ,2 ,2 ,2 ,1) now I ignored the ordinal scale and treated them as factors to fit the multinomial logit regression require(car) a<-as.factor(a) b<-as.factor(b) c<-as.factor(c) multinom(formula = a ~ b + c) Call: multinom(formula = a ~ b + c) Coefficients: (Intercept) b2 b3 b4 b5 c2 c3 c4 c5 2 0.3410779 1.009797 41.80056 45.22081 -13.02923 -0.5229982 0.9216514 0.2170273 -18.03928 3 -1.4697131 2.698228 44.91938 47.04268 -16.24570 -0.7341395 0.7088424 1.2495310 20.70641 4 -46.0095393 33.603384 75.13911 79.00502 56.91264 -7.4198320 13.0220759 14.2526951 33.85774 Std. Errors: (Intercept) b2 b3 b4 b5 c2 c3 c4 c5 2 1.2654428 0.6530052 0.4659520 0.5495402 NaN 1.337075e+00 1.4180126 1.4993079 8.028986e-16 3 1.6649206 0.9361438 0.5123106 0.5879588 2.446562e-15 1.640462e+00 1.7003411 1.7558418 8.601766e-01 4 0.3399454 0.4767032 0.3699569 0.4144527 3.321501e-11 6.973173e-08 0.6549144 0.6953767 8.601766e-01 Residual Deviance: 328.1614 AIC: 382.1614 I think I found the mistake....the column b5 is empty for a1 and a2. table(b,c,a) , , a = 1 c b 1 2 3 4 5 1 0 3 2 2 0 2 1 7 1 0 0 3 0 0 0 0 0 4 0 0 0 0 0 5 0 0 0 0 0 , , a = 2 c b 1 2 3 4 5 1 1 5 2 2 0 2 1 12 21 4 0 3 0 1 6 1 0 4 0 2 1 1 0 5 0 0 0 0 0 But do you know how to solve this problem? |
I need to create similar table using LaTeX: I have tried to use tabular and \multicolumn, but every time I get something wrong. Could someone help me? \documentclass{article} \begin{document} \begin{tabular}{ | l | l | l | l | l | l | l | l | l | l | l | l | l | l | l | l | } \hline \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ \\ \hline \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ \\ \hline \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ & \ \\ \hline NAME & L & & & M & & & N & & & O & & & K & & \\ \hline & L1 & L2 & L3 & M1 & M2 & M3 & N1 & N2 & N3 & O1 & O2 & O3 & K1 & K2 & K3 \\ \hline A & 31 & 11 & 22 & 5 & 1 & 5 & 5 & 1 & 5 & 2 & 0 & 0 & 4 & 2 & 0 \\ \hline B & 11 & 10 & 4 & 23 & 6 & NA & 8 & 0 & 2 & 1 & 0 & 1 & 1 & 1 & 1 \\ \hline C & 7 & 4 & 2 & 3 & 1 & NA & 2 & 3 & 1 & 2 & 3 & 1 & 4 & 2 & 1 \\ \hline D & 21 & 8 & 9 & 29 & 3 & 15 & 22 & 3 & 2 & 6 & 0 & 0 & 3 & 4 & 0 \\ \hline \end{tabular} \end{document} | When combining multirow and multicolumn in the same cell of a table I am getting extra vertical lines: \documentclass[plain]{article} \usepackage{multirow} \pagestyle{empty} \begin{document} \begin{tabular}{|l|l|l|l|}\hline \multirow{10}{*}{numeric literals} & \multirow{5}{*}{integers} & in decimal & \verb|8743| \\ \cline{3-4} & & \multirow{2}{*}{in octal} & \verb|0o7464| \\ \cline{4-4} & & & \verb|0O103| \\ \cline{3-4} & & \multirow{2}{*}{in hexadecimal} & \verb|0x5A0FF| \\ \cline{4-4} & & & \verb|0xE0F2| \\ \cline{2-4} & \multirow{5}{*}{fractionals} & \multirow{5}{*}{in decimal} & \verb|140.58| \\ \cline{4-4} & & & \verb|8.04e7| \\ \cline{4-4} & & & \verb|0.347E+12| \\ \cline{4-4} & & & \verb|5.47E-12| \\ \cline{4-4} & & & \verb|47e22| \\ \cline{1-4} \multicolumn{3}{|l|}{\multirow{3}{*}{char literals}} & \verb|'H'| \\ \cline{4-4} & & & \verb|'\n'| \\ \cline{4-4} & & & \verb|'\x65'| \\ \cline{1-4} \multicolumn{3}{|l|}{\multirow{2}{*}{string literals}} & \verb|"bom dia"| \\ \cline{4-4} & & & \verb|"ouro preto\nmg"| \\ \cline{1-4} \end{tabular} \end{document} Notice the vertical lines in the char literals and string literals cells (which should span three columns). How can they be avoided? |
sudo: /etc/sudoers is mode 0777, should be 0440 sudo: no valid sudoers source found, quitting sudo: unable to initialize policy plugin I have Ubuntu Server 12.04.4 LTS and this sudo problem, i cant use sudo command, please help everyone, how to fix this sudo error. Please Help! | I am getting sudo errors, how do I fix this error? sudo: /etc/sudoers is mode 0777, should be 0440 sudo: no valid sudoers sources found, quitting |
If there aren't pointers exposed to implement in java does Nullpointer exception need to be changed to Nullreference exception? | Was this an oversight? Or is it to do with the JVM? |
I downvoted an answer 17 seconds after it was posted, and left. I came back 17 minutes later (what a coincidence) and the post had been edited, but the system didn't let me undo my vote. I believe it was because the edits took place during the grace period and weren't registered. Is that so? I wish I were able to remove my downvote. | A little background: I do not know what the specifics are, but I've noticed that a quick edit after a post will often times not result in an edit being posted. It's as if there was no edit. Edit: According to Bart this amount of time is five minutes. The problem: A user made a really bad post (said that ~ in C# wrt integers was used for deconstruction). I down-voted said post. Post quickly disappeared (I guess poster realized they screwed up and took back the post). Later, I come back and see my down vote but the answer is now correct (that ~ is the bitwise complement operator). I try to get rid of my down vote because it is no longer appropriate. However, it has been about half an hour and there is no edit posted (presumably the poster made an edit within the non-posting edit window) so I can't take my vote back. Suggested solution: If post gets edited (even within the non-post edit window) mark all the votes as changeable. I would guess that this would either involve an update on a table of votes or adding a column for last edit time which is not bypassed by the grace period. I realize that this may be an entirely non-trivial change, but unless the non-posting of edits is somehow changed to make sure the edit was trivial it seems this is necessary. |
Suppose we have $T_i,i=1..n$ i.i.d. with unknown distribution and we want to estimate $E[T]$. Note that in this setting we are not estimating E[T] as a parameter of a parameter-dependent family of distributions, therefore it is difficult to attach a meaning to a likelyhood function: $L[E[T]]=P(T_i|E[T])$ as it would be done when for example estimating $\mu$ from maximum likelyhood, knowing that the underlying distribution is Gaussian. Again what we would probably do is computing $\overline{T}=\frac{1}{n}\sum_i T_i$. And we would be sure that the estimator would be consistent and its variance would go to zero. For example we have trivially: $E[\overline{T}]=E[T_i]$ and: $\sigma^2[\overline{T}]=O(1/n)$ supposing that $T_i$ has finite variance. Here is the question: can we prove that $\overline{T}$ is optimal in some way? To me conceptes from MLE estimators or sufficient statistics are a bit difficult to apply, since $E[T]$ is not a parameter of the distribution but maybe I am missing something? Can we "derive" the sample mean estimator to be optimal according to some criterion in the general case and without making assumptions on the underlying distributions ? | While learning about Random variables I came across the mean of random variable X. The definition says that the expected value of random variable E(X) = Mean of Random variable X I am not able to understand why is that so. Can any one please help me with it |
I am cooking a pork butt roast sous vide. I am following this recipe. My bag had no or very little air in it after sealing and when the cooking started. Since cooking for a few hours the meat has shrunk considerably in size within the bag. But the bag also has new air in it. Enough to make it float. I am worried I could have bad bacteria and make my guests sick. Here is more of my thoughts: 1) According to some articles I have read this could simply be vapor. At 165F the meat is hot enough to release some water to vapor. 2) Maybe while coming to temperature some bacteria did grow, but at 165F, that bacteria is now dead. Even though the air remains, the meat is safe to eat. The dead bacteria and/or their waste are not harmful. 3) I grew a bunch of bacteria and this is not safe to eat. Here are some pictures: FYI, This was the only other SO post I found: | I am making this for pulled pork, planning to do 24 hours at 75 deg C. After coming home from work, I discovered I did not suck the air out properly and there is a big bubble in the bag, causing it to float to the top and for the top of the meat to be not submerged properly. I have now put a bowl on top of it to weigh it down for the next 12 hours. Will it still be safe to eat? Will it taste good? |
I am asking about the probability that the number of Fermat primes is infinite. There is a lot of things similar to the case of Mersenne primes. But it was conjectured that the number of Mersenne primes is infinite and the number of Fermat primes is finite. | A Mersenne prime is a prime of the form $2^n-1$. A Fermat prime is a prime of the form $2^n+1$. Despite the two being superficially very similar, it is conjectured that there are infinitely many Mersenne primes but only finitely many Fermat primes. Is there an intuition that can help me appreciate the nature of that seemingly paradoxical difference? |
JVMS heap usage and GC is working as expected but we are still observing more than 90% MEM usage in Linux top command. Please advise. | This is a about how Unix operating systems report memory usage. Similar Questions: I have production server that is running Debian 6.0.6 Squeeze #uname -a Linux debsrv 2.6.32-5-xen-amd64 #1 SMP Sun Sep 23 13:49:30 UTC 2012 x86_64 GNU/Linux Every day cron executes backup script as root: #crontab -e 0 5 * * * /root/sites_backup.sh > /dev/null 2>&1 #nano /root/sites_backup.sh #!/bin/bash str=`date +%Y-%m-%d-%H-%M-%S` tar pzcf /home/backups/sites/mysite-$str.tar.gz /var/sites/mysite/public_html/www mysqldump -u mysite -pmypass mysite | gzip -9 > /home/backups/sites/mysite-$str.sql.gz cd /home/backups/sites/ sha512sum mysite-$str* > /home/backups/sites/mysite-$str.tar.gz.DIGESTS cd ~ Everything works perfectly, but I notice that Munin's memory graph shows increase of cache and buffers after backup. Then I just download backup files and delete them. After deletion Munin's memory graph returns cache and buffers to the state that was before backup. Here's Munin graph: Externally hosted image was a dead link. |
I am building a simple message app, at the moment I would like to view the users image next to their text. I am trying to get the users image from the firebase database. However, whenever I try to getValue() of the an image the app crashes. If I choose to replace imageURI with an image link, then I see it works with that link. 08-27 23:14:02.392 4817-4817/com.myproj.blogapp E/UncaughtException: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference at com.myproj.blogapp.MessageAdapter$1.onDataChange(MessageAdapter.java:79) at com.google.android.gms.internal.to.zza(Unknown Source) at com.google.android.gms.internal.vj.zzHX(Unknown Source) at com.google.android.gms.internal.vp.run(Unknown Source) at android.os.Handler.handleCallback(Handler.java:739) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:145) at android.app.ActivityThread.main(ActivityThread.java:5938) at java.lang.reflect.Method.invoke(Native Method) at java.lang.reflect.Method.invoke(Method.java:372) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1400) @Override public void onBindViewHolder(final MessageViewHolder viewHolder, final int index) { final Message c = messagesList.get(index); final String sender = c.getFrom(); databaseReference = FirebaseDatabase.getInstance().getReference().child("Users").child(sender); databaseReference.addValueEventListener(new ValueEventListener() { @Override public void onDataChange(DataSnapshot dataSnapshot) { imageUrl = dataSnapshot.child("image").getValue().toString(); //error on this line viewHolder.setUserimage(context,imageUrl); String name = dataSnapshot.child("name").getValue().toString(); viewHolder.displayName.setText(name); } @Override public void onCancelled(DatabaseError databaseError) { } }); viewHolder.messageText.setText(c.getMessage()); viewHolder.time.setText(EpochtimeToDateAndTimeString(c.getTime())); } | What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them? What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely? |
I'm just trying to make an icosahedron. I know I need to reduce the subdivisions of the default mesh to 1, but the UI has changed and I can't find where to do that. | The tutorial I read is based on 2.79. So I'm not sure if it's still the same name in 2.8. But I can't find anything providing similar functionalities. |
I want to plastic type gloss and reflection of light on it. Please help to add those effect. | I'm pretty new to this and this is my first question here, any help would be greatly appreciated. So basically what I want to achieve is a floor material as seen in this photo... ...the reflections are very crisp but dim. With a glossy shader I get the following results: First picture: reflections are blurry Second picture: roughness of the material looks right but reflection is bright red Third picture: If tinted in any other color than white, it seems to produce the result I want. Reflection is sharp and gets tinted blue. What I need is the reflection to be tinted white. Thanks for any help. |
Where are folks storing and sharing their Python geoprocessing scripts? For example, I know that has some shared scripts. ESRI is phasing-out , which is still really handy, and directing people to the . What other repositories are available for sharing geoprocessing scripts? | I will be writing scripts for ArcGIS Desktop in Python with ArcPy. Is there a community or open source project where code and models can be shared? |
This could be an interesting Question. I Found and iPhone 5S, I handed it into the police. After 2 Months they returned the Phone, no one claimed it. I have a Sticker on the back of the phone with police details on it. So in our country, that is proof of ownership. I am now the new owner of this phone. BUT.....It is a brick, as the security has been enabled. I have a start up screen that looks like a brand new phone and I must enter an iCloud account and password. I do not have this information. I have contacted Apple Help USA, They say I need a court summons ??? WHAT!!! I contacted Apple technical Support, ( basically they said NO ) SO. the Question is.... Is there a way around this? ( I am happy to send a photo with the police details on it. To prove ownership.) Thanks Anthony | I bought a used iPhone 4. The previous owner re-set the phone, but did not remove the device from their iCloud. It is asking me for their iCloud information when I try to set-up the phone. I don't have contact with the previous owner anymore. Is there a way to remove the device from their iCloud so I can use a new one? |
I labeled my lemma with \label{lem1} and referred to it later using \autoref{lem1}. However, what was printed was "Theorem 2.1" where it should really say "Lemma 2.1". How do I fix this? \documentclass[a4paper, 12pt, twoside]{thesis} \usepackage{verbatim} \usepackage{amssymb,amsmath} \usepackage{amsthm,amsfonts,amscd,amsrefs} \newtheoremstyle{component}{}{}{}{}{\itshape}{.}{.5em}{\thmnote{#3}#1} \theoremstyle{component} \newtheorem*{component}{} \begin{document} \begin{lemma} \label{lem1} This is a lemma. \end{lemma} By \autoref{lem1}, we have.. \end{document} | When I define amsthm theorem environments with shared counters, autoref messes up the names of the references. For example, in the output below, we should have "Definition 2" instead of "Theorem 2". \documentclass{article} \usepackage{amsthm} \usepackage{hyperref} \theoremstyle{theorem} \newtheorem{theorem}{Theorem} \theoremstyle{definition} \newtheorem{definition}[theorem]{Definition} \begin{document} \begin{theorem} \label{wonderful-theorem} This is a wonderful theorem. \end{theorem} \begin{definition} \label{awesome-definition} This is an awesome definition. \end{definition} Look at the wonderful \autoref{wonderful-theorem} and the awesome \autoref{awesome-definition}. \end{document} |
Let's say free electrons are contained in a small cloud because of electrostatic forces confining them. Now, if those walls vanish, the cloud will expand very fast because of the coulomb force inducing repulsion between alike charges. I suppose there is now a current in the shape of a radially expanding flux, centered around the center of mass of the electron cloud. If one checks a small area of the sphere surrounding the cloud before its expansion, once the cloud starts expanding, a number of negative charges will move through it, so we have coulombs per second, i.e. amperes. What does that mean for the magnetic field created by this varying electric field? Since the magnetic field is encircling the axis of the current, i.e. it is perpendicular to its direction, I would expect the ampere effect, i.e. that parallel wires with same sign current attracts each other. But that would seem to mean the lines of the electrons moving away from the center will contract and make the sphere collapse. What is the real consequence of such a setting? A slowing down, like an inductor resists current change? Possibly a rebound or even an oscillating cloud? EDIT: Someone explains to me how a question already assuming the correct answer is a duplicate. I understand it answers my question yes, but not as a duplicate. | We now ask about the magnetic field produced by the currents in this situation. Suppose we draw some loop $\Gamma$ on a sphere of radius $r,$ as shown in Fig. 18–1. There is some current through this loop, so we might expect to find a magnetic field circulating in the direction shown. But we are already in difficulty. How can the $\boldsymbol B$ have any particular direction on the sphere? A different choice of $\Gamma$ would allow us to conclude that its direction is exactly opposite to that shown. So how can there be any circulation of $\boldsymbol B$ around the currents? This is an excerpt from Feynman's Lectures on Physics; here he explains how there exists no magnetic field for a spherically symmetric current & that he proves later using Maxwell's third equation including the term $\frac{\partial \boldsymbol E}{\partial t}$. But I've not understood his reasoning; how by changing $\Gamma$, the direction of the magnetic field be different? I'm failing to visualise it. So, could anyone please help me explain how by changing the loop, the direction of the magnetic field be reversed? |
I have the following problem Let $n$ be a natural number. What is the sum of $1+2+3+...+(n-1)+n$ I'm not 100% certain what would be a correct way of calculating it. What I've done so far is look at the first and second first and last term. $1+n$ and $2+(n-1)$. So I have $2n-1+2+3+...$. So that means the sum is $∞$ | Apparently $1+2+3+4+\ldots+n = \dfrac{n\times(n+1)}2$. How? What's the proof? Or maybe it is self apparent just looking at the above? PS: This problem is known as "The sum of the first $n$ positive integers". |
Is there a good practice to follow when creating a design in Photoshop so that it's easy to change colors later on? For example, if it's possible to create a color swatch where I reference a color slot in my swatch instead of the color code. So PS would know that in that layer I'm using the color slot #3 from my swatch. When I later change the color in slot #3 then all places referencing that color would update. | I'm looking for a way to use one color in multiple different layers, and then be able to change that color in all the layers in one single place. Lets say that I have four layers using #ffffff. Now I want to know what my design looks like with #ffff00 instead. How can I do this without manually changing all four layers? I can add that adjustment layer on hue/saturation is not really what I'm looking for. What I need is something like "change all #ffffff to #ffff00." |
I only need a couple of sentences to explain, but I don't know how to word it, please help! I do not need an algebraic proof, just a sentence or two to explain why the output is always even. | This is what I have so far, but I don't feel like its a full explanation The even function gets rid of the negation Since $ h(x) $ is even then $ h(x)=h(-x) for \ all \ x \ $ $ f(x) = g(h(x)) $ $ f(-x) = g(h(-x)) = g(h(x)) \ or \ g(-(-h(x))) = g(h(x)) $ therefore $ f(x) $ is even Thanks in advance!! |
I would like to show that polynomial $x^3-xy^2+y+1$ is irreducible over $\mathbb{Q}(x)[y]$. I thought I could find the roots in using $\dfrac{-b\pm\sqrt{b^2-4ac}}{2a}$, but I found that the two roots are $\frac{-1±\sqrt{4x^4+4x+1}}{-2x}$. These two roots couldn't be in $\mathbb{Q}(x)$. Is anyone could help me to solve this problem? | I know that $\mathbb{Q}[y][x]=\mathbb{Q}[y,x]$; thus, we can see this polynomial as a polynomial with variable $x$ and with coefficients in $\mathbb{Q}[y]$. Someone explains to me that we could use Gauss's Lemma to reduce to proving irreducibility over the $\mathbb{Q}(x)[y]$ where $\mathbb{Q}(x)$ is the fraction field and after apply Eisenstein for the prime $y+1$. I am blocked for a while on this problem. Could anyone solve this problem? |
I've been trying to find the name of a movie. It was a horror from the 80's most likely. There was a bad guy that would transform into a werewolf like creature. The protagonist was a young male about 18 years old. I only caught the last 20-30 minutes of the movie. The boy and his family (no dad that I remember) were hiding out in a cabin in the woods. He was preparing for the bad guy to arrive by making molotov cocktails and other homemade weapons. He also wields a lever action rifle. Eventually, the bad guy shows up in his car, transforms, some molotov cocktails were thrown, the werewolf is injured, and the kid tracks him into the woods and kills him. Anyone have any idea what movie this is? | For years I've been trying to find this movie I saw on TV once. I only saw the end. It featured a teenage boy (about 18 years old) and his family hiding out in a cabin. The kid is making molotov cocktails and preparing for something. Sure enough two bad guys show up and I think one of them had a golden pistol. They start fighting and one of the guys turns into a werewolf type creature. The kid wounds it and tracks it through the woods to finish it off with his lever action rifle. Anyone know the name of this movie? I saw this probably mid to late 90s. I'm guessing it was an 80's American film. It was live action. |
Can you give any examples? How does this relate to the Taylor series? Is it trye that all analytic functions are smooth, but not all smooth functions are analytic? | I saw the following (“roughly speaking”, like the author says) definition of a Lie group in ‘Group theory in Physics’, by Wu-Ki Tung: “Roughly speaking, a Lie group is an infinite group whose elements can be parametrized smoothly and analytically.” After this, I was asking myself if I really already know the difference between these terms. Because, what I know about 1 - analytic: if we say that a function is analytic at a point it means that its derivative is defined at this point and at the points of its neighborhood; 2 – continuous: a function is continuous at a point if you can write a neighborhood of this point where this function is still defined (and this is why those three conditions we learn in Calculus, including that one with the limit); 3 – smooth: I am not sure, but I think it is related to the differentiability of the function. I think this may be a silly question, but I would thank you for answering |
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