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In The Name of the Doctor, we are technically seeing a saved version of River Song from the Library, meaning she's definitely dead. If this is so, where in the timeline does the Doctor tell her his name? This obviously must have been before the events of Silence in the Library (from River's timeline point of view). However, she seems to be making no appearance in the 50th anniversary special, so where (when) does the occasion occur when the Doctor tells River his name, or is this something which hasn't been disclosed yet?
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In series 6, The Doctor lies that he told River his name (which River falsifies in the end of the episode). Yet in The Name of The Doctor she knows The Doctor's real name and even opens The Doctor's tomb with it. Also, The Tenth Doctor says that there was only one situation where he could possibly tell her his name. What of it? So where, when & how exactly does River come to know The Doctor's name?
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Let $f: \mathbb{R} \to \mathbb{R}$ be continuous at $0$ and $f(x+y) = f(x) + f(y)$ for all $x, y$ in $\mathbb{R}$. Show that there is a real number $c$ such that $f(x) = cx$. I'm not sure about how to do show this, I can tell that $f(0) = 0$ and that from continuity at $0$ we get $|f(x)| < \epsilon$ for $x$ in some delta neighborhood of $0$. Can anyone help me with this please. Edit: please note that the function is only continuous at $0$ so Cauchy functional equation properties can't be used here.
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The asks about functions $f \colon \mathbb R \to \mathbb R$ such that $$f(x+y)=f(x)+f(y).$$ It is a very well-known functional equation, which appears in various areas of mathematics ranging from exercises in freshman classes to constructing useful counterexamples for some advanced questions. Solutions of this equation are often called . Also a few other equations related to this equation are often studied. (Equations which can be easily transformed to Cauchy functional equation or can be solved by using similar methods.) Is there some overview of basic facts about Cauchy equation and related functional equations - preferably available online?
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Should I use Video options or Video's options when referring to a few video properties that can be edited?
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I am firmly convinced he is innocent and his accusation is the result of the police conspiracy. I am firmly convinced he is innocent and his accusation is the result of the police's conspiracy. Which sentence do you think is a better choice?
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NOTE: this question was previously marked as a duplicate. It's subtly different, though: the asked what the difference is between the two syntaxes; whereas I know there's no difference in meaning, and I'm asking in that case why Java allows both. Why does Java allow both int x[]; and int[] x; when I declare an array? The latter makes much more sense: the variable is called x, not x[], and its type is int[], not int. Why not just enforce this? Allowing two different syntaxes seems just to invite confusion and inconsistency. It even appears to make it possible to declare a two-dimensional array as int[] x[]; which is bordering on unreadable. Is it something borrowed from C? (Why would C do it that way round, anyway?)
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I have recently been thinking about the difference between the two ways of defining an array: int[] array int array[] Is there a difference?
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Input: file with sorted lines Output: file with 'unique' lines that match adjacent lines if we are to remove all digits Example Input abbylove2007 abbylove2008 abbylove2012 AbbyLove2014 abby1994lover abby2007lover abbylovesaal2018 abbylovesbsb2003 Output abbylove2007 abby1994lover Here abbylove2007 and abby1994lover are left since there are more than one adjacent line that matches abbylove\d+ and abby\d+lover
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Input: file with sorted lines Output: file with (first or any) unique line ids from the input file Example Input abbylove abbylove abbylove abbylover abbylover abbylovesyou abbylovesyou abbylsmith abbylsmith abbylyn abbylynn Output 1 4 6 8 10 11 0-indexed also OK. How to create such an output? I don't find such an option in shell uniq and sort commands. Updated. I'm trying to find unique adjacent lines from a file that differs only in years, that they contain. For example, I'd like to filter the file abbylove2016 abbylove2017 abbylove2018 abb1999ylover abb2005ylover abbyloves2001you abbyloves2006you abbylsm1980ith abbylsm2010ith abbylyn2002 abbylynn1999 and get only abbylove2016 abb1999ylover abbyloves2001you abbylsm1980ith abbylyn2002 abbylynn1999 I thought removing years could help...
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I moved some mp3s to my iPhone using AirDrop expecting they would be available in the Music app, but I can't seem to find them. Where can I find them on my phone? There was no error or anything saying the files didn't go through. It appears as if they have been copied to my phone.
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Where do AirDrop files go when I transfer them between an iPad, iPhone and iPod? I AirDropped some Google Docs from my iPad to my iPhone but nothing happened; where did my files go? The file was a list of tools.
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As noted in , kerning, spacing, and tracking are turned off by default in microtype. Why is that? Are there good arguments against using it? What would be the pros and cons of activating it? Now that we're at it, what are the pros and cons of the other options (protrusion, expansion, =auto)?
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According to the microtype manual, Kerning, Spacing and Tracking are not enabled by default in pdftex (>= 1.4). What are the reasons for this?
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I want to prove the law of excluded middle: $A$ Thus $B ∨ ¬B$ under Copi's logic system.('A' means any premise. I want to derive the law of excluded middle from any premise, not means no premise) Copi system is constructed by 19 rules. 9 rules of inference: modus ponens(MP), modus tollens(MT), hypothetical syllogism(HS), disjunctive syllogism(DS), constructive dilemma(CD), simplification(Simp), conjunction(Conj), addition(Add), absorption(Abs) 10 rules of replacement: De Morgan's rule(DM), Commutativity(Com), Associativity(Assoc), Distrivution(Dist), Double Negation(DN), transposition(Trans), Material implication(Impl), Material equivalence(Equiv), exportation(Exp), Tautology(Taut) I do not want to use conditional proof and indirect proof(reductio ad absurdum). Can I prove the above statement using only 19 rules?
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I'm taking a course from Stanford in Logic. I'm stuck with an exercise where I'm doing some proof. The Fitch system I'm given only allows $ \land $ introduction and elimination $ \lor $ introduction and elimination $ \to $ introduction and elimination $ \equiv $ introduction and elimination $ \lnot$ introduction and $ \lnot \lnot $ elimination but not $ \bot $ introduction and elimination I've been struggling to prove the law of excluded middle (``p ∨ ¬p`) within this system. All of the proofs I've seen online make use of $\bot$ elimination to prove it by contradiction: | ~(p | ~p) (assumption) | | p (assumption) | | p | ~p (or introduction) | | $\bot$ | | | ~p (assumption) | | p | ~p (or introduction) | | $\bot$ | | (p | ~p) (proof by contradiction) Since I can't use $\bot$ elimination, I was trying to do this with $ \lnot$ introduction: | ~(p | ~p) (assumption) | | ??? | ~(p | ~p) => x | | | ??? | ~(p | ~p) => ~x | p | ~p (not introduction) but I just can't get it. I can't figure out how to get x and ~x. Is this provable without $\bot$ elimination? If so, what are the steps? Background: What I'm ultimately trying to prove is : Given p ⇒ q, use the Fitch System to prove ¬p ∨ q. I'm able to prove that p ⇒ ¬p ∨ q and that ¬p ⇒ ¬p ∨ q, but I need to be able to plug p ∨ ¬p into the proof to be able to do 'or elimination'.
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Show that $\mathbb{Q}(\sqrt{2 +\sqrt{2}})$ is a cyclic quartic field i.e. is a galois extension of degree 4 with cyclic galois group with some elementary algebra, $x - \sqrt{2 +\sqrt{2}} = 0 \implies x^2 = 2+\sqrt{2} \implies (x^2 - 2)^2 = 2 \implies x^4-4x^2+2=0$ is the minimal polynomial and is Eisenstein at 2 so irreducible which gives seperable. and the roots of $x^4-4x^2+2=0$ are $\pm \sqrt{2 \pm \sqrt{2}}$ again found with elementary algebra. So the splitting field is clearly a degree 4 extension. Now I've confused myself a bit trying to work out all the automorphisms since the polynomial is seperable I know $\mid AUT(\mathbb{Q}(\sqrt{2 +\sqrt{2}})/\mathbb{Q}\mid = [\mathbb{Q}(\sqrt{2 +\sqrt{2}}) : \mathbb{Q}]$ so there are 4. So it needs to be ismorphic to $\mathbb{Z}_4$ I think the only automorphisms are id, $\sigma : \sqrt{2 +\sqrt{2}} \mapsto -\sqrt{2 +\sqrt{2}}, \tau : \sqrt{2 -\sqrt{2}} \mapsto -\sqrt{2 +\sqrt{2}} $
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So I want to show that $\mathbb{Q}(\sqrt{2+\sqrt{2}})$ is Galois over $\mathbb{Q}$ and determine its Galois group. My thoughts are as follows: Define $\alpha := \sqrt{2+\sqrt{2}}$. Then it is easily shown that $\alpha$ satisfies $\alpha^4-4\alpha^2+2=0$. Define $f(x) := x^4-4x^2+2$. Then $f$ is irreducible over $\mathbb{Q}$ by Eisenstein with $p=2$. So we have that $f$ is the irreducible polynomial for $\alpha$ over $\mathbb{Q}$. Further $|\mathbb{Q}(\alpha):\mathbb{Q}|=4$. For $\mathbb{Q}({\alpha})$ to be Galois, it must contain all roots of $f$. Define $K=\mathbb{Q}(\alpha)$ for convenience. Define $\alpha := \alpha_1$. Since $f$ has only even powers, we know that $-\alpha := \alpha_2$ is a root, and therefore contained in $K$ since $K$ is a field. We note that the other two roots are $\alpha_3=\sqrt{2-\sqrt{2}}$ and $\alpha_4=-\sqrt{2-\sqrt{2}}$. So in order to show $K$ is Galois, it must be shown that $\alpha_3$ and $\alpha_4$ lie in $K$. Now $\alpha_1^2=2+\sqrt2$ and so $\sqrt2 \in K$. Thus $-\sqrt2 \in K$ since $K$ is a field. Can somebody explain why $\alpha_3$ and $\alpha_4$ lie in $K$? Next we are to determine the Galois group of $K$. Assuming $K$ is Galois, since it has degree $4$ over $\mathbb{Q}$ (shown earlier), we know that its Galois group has size $4$. There are only two groups of size $4$, namely $V_4$ and $C_4$, the Klein four group and the cyclic group of order $4$. How do we determine which of these choice is in fact the Galois Group?
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okay so i understand that List is an interface that ArrayList implements but what's the actual point of doing it ? what pros do i get from naming it as List not ArrayList ? first example ArrayList<String> x= new ArrayList<String>(); second example List<String> x= new ArrayList<String>(); what'd be a real life example where it's better to use either ?
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I have seen this mentioned a few times and I am not clear on what it means. When and why would you do this? I know what interfaces do, but the fact I am not clear on this makes me think I am missing out on using them correctly. Is it just so if you were to do: IInterface classRef = new ObjectWhatever() You could use any class that implements IInterface? When would you need to do that? The only thing I can think of is if you have a method and you are unsure of what object will be passed except for it implementing IInterface. I cannot think how often you would need to do that. Also, how could you write a method that takes in an object that implements an interface? Is that possible?
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Question My thought: As far as the given equality is concerned, I can prove that the relation is true by calculating some general mathematics proving by L.H.S = R.H.S method(given in the picture below) But I am curious if there is any specific formula of combinatorics which can fetch this equality.(without using this general LHS-RHS method) Please help me into this.
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While thinking about I found out that this equality might be useful there: $$n\cdot 1 + (n-1)\cdot 2 + \dots + 2\cdot (n-1) + 1\cdot n = \frac{n(n+1)(n+2)}6$$ To rewrite it in a more compact way: $$\sum_{k=1}^n k(n+1-k)=\frac{n(n+1)(n+2)}6.$$ This equality is relatively easy to prove: $$\sum_{k=1}^n k(n+1-k)= (n+1)\sum_{k=1}^n k - \sum_{k=1}^n k^2 = (n+1) \frac{n(n+1)}2 - \frac{n(n+1)(2n+1)}6 = n(n+1) \left(\frac{n+1}2-\frac{2n+1}6\right) = n(n+1)\frac{3(n+1)-(2n+1)}6 = \frac{n(n+1)(n+2)}6.$$ (We only used the known formulas for the and the .) Are there some other nice proofs of this equality? (Induction, combinatorial arguments, visual proofs, ...) EDIT: Now I found another question which asks about the same identity: (I have tried to search before posting. But the answers posted here so far gave me some new ideas for good keywords to search which lead me to finding that question.) The questions are, in my opinion, not exact duplicates since the other question asks specifically about combinatorial proofs and my question does not have that restriction. But I agree that this is a very minor distinction. In any case, if you think that one of them should be closed as a duplicate, then you can vote to close. I will refrain from voting to close/reopen on this question. (If one of the two questions is voted to be a duplicate of the other one, they probably cannot be merged, since the summation variables are off by one.)
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What is the maximum value of $x^2+y^2$, where $(x,y)$ are solutions to: $$2x^2+5xy+3y^2=2$$ and $$6x^2+8xy+4y^2=3$$ Note: Calculus is not allowed. I tried everything I could but whenever I got for example or $x^2+y^2=f(y)$ or $f(x)$ the function $f$ would always be a concave up parabola, so I could not find a maximum for either variable. And by the way I know that you can solve for $x$ and $y$ using the quadratic formula and get $4$ different solutions but I am looking for less messy way. I've asked this question , but I didn't get the nice answer I wanted. Thanks. This question came from a math competition from the Math Honor Society, Mu Alpha Theta.
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What is the maximum value of $x^2+y^2$, where $(x,y)$ are solutions to $2x^2+5xy+3y^2=2$ and $6x^2+8xy+4y^2=3$. (calculus is not allowed). I tried everything I could but whenever I got for example $or$ $x^2+y^2=f(y)$ or $f(x)$ the function $f$ would always be a concave up parabola, so I could not find a maximum for either variable. However, I also don't see how you could solve it if you leave both variables on one side. And by the way I know that you can solve for $x$ and $y$ using the quadratic formula and get $4$ different solutions but I am looking for a much more efficient way than that. This question came from a math competition from the Math Honor Society, Mu Alpha Theta.
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Is there any way I can 'undo' the factorial operation? JUst like you can do squares and square roots, can you do factorials and factorial roots (for lack of a better term)? Here is an example: 5! = 120. Is there a way I can work out the number that must be factorialed (??) to give the answer 120?
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I don't want to do this through trial and error, and the best way I have found so far was to start dividing from 1. $n! = \text {a really big number}$ Ex. $n! = 9999999$ Is there a way to approximate n or solve for n through a formula of some sort? Update (Here is my attempt): Stirling's Approximation: $$n! \approx \sqrt{2 \pi n} \left( \dfrac{n}{e} \right ) ^ n$$ So taking the log: $(2\cdot \pi\cdot n)^{1/2} \cdot n^n \cdot e^{-n}$ $(2\cdot \pi)^{1/2} \cdot n^{1/2} \cdot n^n \cdot e^{-n}$ $.5\log (2\pi) + .5\log n + n\log n \cdot -n \log e$ $.5\log (2\pi) + \log n(.5+n) - n$ Now to solve for n: $.5\log (2\pi) + \log n(.5+n) - n = r$ $\log n(.5+n) - n = r - .5 \log (2\pi)$ Now I am a little caught up here.
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I have a PC which overheats and shuts down without warning. I installed lm-controls and fancontrol. I ran sensors detect and said yes to all questions. I typed sudo service kmod start When I try pwmconfig, I get There are no pwm-capable sensor modules installed When I typed sensors, I saw the CPU was already over 80 Celsius. So I turned it off. sensors: coretemp-isa-0000 Adapter:ISA adapter Core 0: + 84.0°C (high = +80.0C, crit = +90.0C) Core 1: + 82.0°C (high = +80.0C, crit = +90.0C) After this, I got lost. I found instructions about how to configure the PC so that such a temperature triggers such and such an action, but this is not really what I want: too complicated. I would like a way to set up all fans at maximum speed, and I don't mind having to type this command each time I turn on this machine. Never mind the temperature, turn them on at full speed from the moment the PC starts working, then maybe it will stay on a little longer... For the moment, it crashes after half an hour, or one hour, depending upon what I'm doing. To manage do-release-upgrade, I had to bring the pc outside when the temperature was around zero. What shall I do during summer?
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I'm trying to control the fan speed of my MSI GS60-2PC laptop on Ubuntu 16.04. But pwmconfig reports that There are no pwm-capable sensors modules installed I'm pretty sure these fans can be controlled, because some utilies on Windows can control them. What I've done I've run sensors-detect (as root) like this: yes | sensors-detect It seems to only detect "coretemp". . Then pwmconfig (as root): pwmconfig And There are no pwm-capable sensors modules installed. I've tried the following things, which didn't work: Adding to grub (and then rebooting): acpi_osi=Linux Adding to grub (and then rebooting): acpi_osi=!Windows 2012 Adding to grub (and then rebooting): acpi_enforce_resources=lax What I get when I run the sensors command acpitz-virtual-0 Adapter: Virtual device temp1: +27.8°C (crit = +105.0°C) temp2: +29.8°C (crit = +105.0°C) temp3: +50.0°C (crit = +100.0°C) coretemp-isa-0000 Adapter: ISA adapter Physical id 0: +48.0°C (high = +84.0°C, crit = +100.0°C) Core 0: +48.0°C (high = +84.0°C, crit = +100.0°C) Core 1: +44.0°C (high = +84.0°C, crit = +100.0°C) Core 2: +46.0°C (high = +84.0°C, crit = +100.0°C) Core 3: +44.0°C (high = +84.0°C, crit = +100.0°C) EDIT:
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Using induction, I have to show that $\forall n \in \mathbb{N}, n \ge 3$ the equation: $$\dfrac{1}{x_1} + \dfrac{1}{x_2} + ... + \dfrac{1}{x_n} = 1$$ has a solution $(x_1, x_2, ..., x_n) \in (\mathbb{N^*}, \mathbb{N^*}, ... \mathbb{N^*})$ (so a solution of all non-zero natural numbers) such that $$x_1 < x_2 < ... < x_n$$ I don't even see how I could prove the base case. If we have: $$p(3) : \dfrac{1}{x_1} + \dfrac{1}{x_2} + \dfrac{1}{x_3} = 1$$ I don't see the $3$ natural numbers that satisfy the equation and at the same time satisfy the condition $x_1 < x_2 < x_3$. So I can't even prove the base case, let alone imply $p(k + 1)$ if I assume $p(k)$ true. Even if I get the equation to a common denominator and multiply, I get: $$x_1 x_2 + x_1x_3 + x_2 x_3 = x_1 x_2 x_3$$ So it didn't really get any more obvious. I thought that these might be the second and third Vieta's formulas for a $3$rd degree polynomial, but I don't see how I could construct a polynomial that has all $3$ of its roots natural and satisfy the condition $x_1 < x_2 < x_3$. Besides, the exercise clearly says that this should be proved using induction.
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I have a hard induction problem here that I feel completly lost on. For every $n\ge3$ there is n different positive integer $a_1,...,a_n$ so that $\frac{1}{a_1}+\frac{1}{a_2}+...+\frac{1}{a_n}=1$. There is only one possible solution for $n=3 $ $\frac{1}{2}+\frac{1}{3}+\frac{1}{6}=1$ for $n=4$ there is 2 possible solutions and they both start with $\frac{1}{2}$. $\frac{1}{2}+\frac{1}{3}+\frac{1}{8}+\frac{1}{24}$ and $\frac{1}{2}+\frac{1}{4}+\frac{1}{5}+\frac{1}{20}$. I think the first one is the one. For $n=5$ there is alot of different possible solutions but it have to start with at least $\frac 13$ I think it have to start with $\frac 12+\frac13$ and then be some kind of sum answer for the last $\frac16$ based on $n$. But I don't know I have tried finding a pattern but not getting anywhere anymore. Any tips on how to tackle a problem like this?
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The green banner next to my reputation counter showed I gained 39 reputation since I last visited the reputation tab. When I look at the reputation events this is not true, I gained 40 reputation. The culprit is easily deductable in this instance, the "removed" downvote is not calculated correctly into the total.
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I noticed that, when I downvote an answer that subsequently gets deleted, the reputation tab in my profile shows a change of -1, even though it's unchanged from when I last checked. Here's a screenshot showing what I mean: The highlighted events that occurred since I last checked are circled; I received an upvote, and downvoted two posts that were removed. Yet, the tab shows a change of 8, when it should be 10.
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Suppose X, Z are normally distributed random variables and independent ($X$ follows $N(\mu,\sigma^{2})$ and $Z$ follows $N(0,\sigma_{z}^{2})$), and that Y=X+Z. What is E[X|Y>c], where c is just a constant - how do you derive this?
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Suppose I have a bivariate normal $(x,y)\sim \mathcal N(0,\Sigma)$ . Is there an easy formula for the expectation $\mathrm E(x\mid y>0)$ ?
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I have two collections: Group = { users: [Array_of_User] } User = { name: _string_ } I'm listing groups ans I'm trying to know in the template if a user is in the groups: mytemplate.js Template.mytemplate.helpers({ groups: function(){ return Groups.find(); }, currentUsername: 'test' }); mytemplate.html <template name="main"> <ul> {{#each groups}} <li> {{#if [the group contains currentUsername] }} contains {{else}} doesn't contain {{/if}} </li> {{/each}} </ul> </template> The question is: what can I put on the helpers and instead of [the group contains currentUsername] to make it work? Also, I'm not saying this is the way to do it. I'm open to any suggestions even if it means I have to change a lot.
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What is the most concise and efficient way to find out if a JavaScript array contains a value? This is the only way I know to do it: function contains(a, obj) { for (var i = 0; i < a.length; i++) { if (a[i] === obj) { return true; } } return false; } Is there a better and more concise way to accomplish this?
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Could it be true: John's paintings of his cat were auctioned. = Some paintings made and owned by John depicting his cat were auctioned.
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I'm not sure of the right place to ask this, but I got confused trying to understand how the computer will interpret the sentence: This is my picture. In actual sense, the real owner of the picture should be the photographer not the person who was photographed... or am I getting something wrong? So, it seems the confusing thing about 'picture' is determining who the real owner of the picture is. So is there a special category for these kind of nouns or an official clarification somewhere? Thanks
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I am a physics student and don't know very much about dark matter nor cosmology. But today I went to a talk in which the speaker showed us this image (or a very similar one): showing how the predictions of the standard model of cosmology having to do with background radiation vary when the ratio of dark matter is modified. I don't know what is the meaning of that plot but it seem that varying the ratio of dark mater produces a very important change in it. My question is: how is that something that does not interact with electromagnetic radiation (as dark matter) has such a drastic effect in CMB?
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After the data from the cosmic microwave background has been collected by WMAP or Planck, what types of analysis is needed to conduct in order to deduce the cold dark matter density and the distribution of matter in the universe? In other words - How the CMB anisotropy measurements giving us evidence for the existence of dark matter/energy? (Any further explanation on the analysis of data is also welcomed.)
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For any sets $A$, $B$, $C$; $(A\cap B)\cup C= A\cap (B\cup C)$ I understand that this means that (A and B) or C = A and (B or C), but how would you prove or disprove these set identities. Any help would be appreciated, Thanks
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I have a set identity: $(A \cap B) \cup C = A \cap (B \cup C)$ if and only if $C \subset A$. I started with Venn diagrams and here is the result: It is evident that set identity is correct. So I started to prove it algebraic: 1) According to distributive law: $(A \cap B) \cup C = (A \cup C) \cap (B \cup C)$ 2) ... I stuck a little. Because $C$ is a subset of $A$. I thought of pulling out: $(B \cup C)$ but it seems wrong step to me. How to prove this identity having in mind that $C \subset A$? Updated Venn diagram for $C ⊈ A$
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How can we prove that if : $n+1|n!+1$ then $n$ is a prime number. My try: I try to do contrapositive: If $n$ is composite then $n+1 \nmid n!+1$ and then to get that if $n$ is composite so $n+1=ab$ when $2 \le a \le n $ so that $a|n+1$ but here I don't have idea how to continue, is this the good way?
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... namely that if $n > 1$ and $(n − 1)!\equiv−1\pmod{n}$, then $n$ is prime. This is for a number theory class I'm in at Penn State. My idea is to follow accordingly, but I can't get it concretely.. Reason by contradiction, suppose that $n$ is not prime. Then $n = ab$, where $1 < a, b < n$ In particular $(n-1)! = ai$ for some $i\in\Bbb{Z}$. $\\$ If $(n-1)! = nj - 1$ for some $j\in\Bbb{Z}$ then it follows that a probably doesn't divide $-1$?
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I want to put output information of my program to a folder. if given folder does not exist, then the program should create a new folder with folder name as given in the program. Is this possible? If yes, please let me know how. Suppose I have given folder path like "C:\Program Files\alex" and alex folder doesn't exist then program should create alex folder and should put output information in the alex folder.
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What is the most elegant way to check if the directory a file is going to be written to exists, and if not, create the directory using Python? Here is what I tried: import os file_path = "/my/directory/filename.txt" directory = os.path.dirname(file_path) try: os.stat(directory) except: os.mkdir(directory) f = file(filename) Somehow, I missed os.path.exists (thanks kanja, Blair, and Douglas). This is what I have now: def ensure_dir(file_path): directory = os.path.dirname(file_path) if not os.path.exists(directory): os.makedirs(directory) Is there a flag for "open", that makes this happen automatically?
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One of my friend is coming to India from US. He bought himself a laptop and a camera which he is using their. Also I requested him to get a Nexus 5 phone for me. Is it possible to bring this phone with sealed box in India without any trouble?
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I bought two smart phones for my father and sister in Europe. Will the customs officer in India (Chennai) give any trouble if I carry two new unopened smart phones with the box in my hand luggage? Also, i'm a student, does this give me any advantage over it?
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I figured out how to use Touch ID for . But when I edit /etc/hosts with my Sublime Text, I still get this window: How can I use Touch ID for messages like this? 😀
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How can I use Touch ID for messages like this?
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There are some questions which were written with my (mainly used) pseudonymous account, but contain some identifiable information, so it would be great if this account could take ownership. As and both merging accounts and dissociating yourself from a question is possible, too, would the Stack Exchange team be willing to change the ownership of these posts?
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I accidentally posted a question without being logged in. Is there a way to associate that question with my account? For more information, visit "" in the . a.k.a. How can you link a registered account to a cookie-based account? a.k.a. How do I merge an unregistered account with a registered account a.k.a. Merging users a.k.a. How do I associate anonymous questions I’ve asked with my registered account? a.k.a. Is there a way to claim an unregistered user? (in case anyone searches with those terms)
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So I've got a brand new laptop for college and it's an Asus Zenbook 14'' with Intel i7 10th gen, and a graphic card- Intel Iris Plus Graphics. Besides running surprisingly slow on i7 processor, Blender won't let me render my animations on the GPU and only works with the CPU. I've tried to search in the Preferences window but I didn't find anything helpful there. What should I do in order to use the GPU?
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I want to enable GPU rendering, but there is no option in User Preferences > System: Why is this? How can I get cycles to render using my GPU?
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I am new to programming and I have basic HTML skills. I am creating a basic web site and I have information in a paragraph and the information is separated by <br> tags. I am looking to add a "copy to clipboard" button and function so that the 16 lines of information are saved to the clipboard. <p> this is the 1st line<br> this is the 2nd line<br> ... this is the 16th line [copy to clipboard] <p>
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What is the best way to copy text to the clipboard (multi-browser)? I have tried: function copyToClipboard(text) { if (window.clipboardData) { // Internet Explorer window.clipboardData.setData("Text", text); } else { unsafeWindow.netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect"); const clipboardHelper = Components.classes["@mozilla.org/widget/clipboardhelper;1"].getService(Components.interfaces.nsIClipboardHelper); clipboardHelper.copyString(text); } } But in Internet Explorer it gives a syntax error. In Firefox, it says unsafeWindow is not defined. A nice trick without using :
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Trying to remember the title of a short story about a robot who survives several generations of a family, and at one point stows away on a spaceship. It was an older story — I want to say pre-1970 — part of an anthology. There was some reason why he stowed away. Maybe he was trying to get home? His longevity figured into the plot somehow. He might have been facing obsolescence.
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I'm looking for a short story from about 50 years ago about a robot who escapes after being slated to be melted down and discovers while in hiding that it has evolved to have some supernatural powers.
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Let $V$ be a finite-dimensional vector space over $F$ with $char(F) = 0$ and $ T: V \rightarrow V $ a linear map. Suppose that $Tr(T^n)=0$ for all $n≥1.$ Show that $T$ nilpotent. I have seen a proof that uses the Fitting's lemma. I believe there should be some straight-forward proof from scratch. Could you help me with some suggestions? Thanks so much.
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Let $A$ be an $n\times n$ complex nilpotent matrix. Then we know that because all eigenvalues of $A$ must be $0$, it follows that $\text{tr}(A^n)=0$ for all positive integers $n$. What I would like to show is the converse, that is, if $\text{tr}(A^n)=0$ for all positive integers $n$, then $A$ is nilpotent. I tried to show that $0$ must be an eigenvalue of $A$, then try to show that all other eigenvalues must be equal to 0. However, I am stuck at the point where I need to show that $\det(A)=0$. May I know of the approach to show that $A$ is nilpotent?
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In 1988 I read a short story about a science fiction author who wrote a new novel and turned it in to his publisher. His publisher turned it down, saying they could not print plagiarized books. The author is confused, knowing it took him a long time to write it. The publisher tells him this book was written a long time ago by another author, and he goes and checks it out, finding to his astonishment that his book, word for word, already exists. He starts work on another book and when it is finished, his publisher turns it down, too, telling him to stop passing off another guy's work as his own. They give him the title of the "original" novel and he looks it up to find that this book, too, exists word for word. Since he is a sci fi author, it occurs to him that a time traveler may be stealing his work, so he writes a new book and pretends to go to sleep, catching a guy who sneaks into his house at night to steal the manuscript. Turns out, the guy is a time traveler who is going to the future, stealing his books, returning to the past and publishing the manuscripts as his own. We had to read this in high school for science fiction class and take a test on it, but I haven't been able to remember the title or author.
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I can't remember the name of the story, and couldn't find anything on Google searches either. The story is about a science fiction writer whose story gets rejected by the publisher because it's word-by-word identical to another story published years ago. The writer then writes another story only to find out that the same author also published this story around the same time as the other one. Our writer then writes a story about a man who uses a time machine to read other people's work in the future and then publishes it in his time. Only to find out that this story was also published by the same guy years ago. The story I'm trying to find out was in the form of letter correspondence between the writer and the publisher. So, does anyone know its title?
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I had Win8 installed on my computer and needed to install Ubuntu, so I took a distro and created a live usb pen and installed it. Everything went fine, well not at first because my computer comes with secure boot, but in the end it was done 0 errors. I have grub working now with ubuntu and windows 8 options. I ran boot-repair to fix my problem and it just added another windows 8 option to boot (one on sda3 another on sda4). So the probem is: in either windows 8 grub options, it starts to load normally, then when it should appear the login screen, a blue screen comes up and says a problem occurred and it reboots. I hope you can help, thank you for your time! Ps.: I had the exact same problem when I was trying to install Ubuntu and I solved it by deleting the partitions where I was supposed to install Ubuntu. Now I don't want to do it because Ubuntu is now successfully installed in those partitions (ext4 + swap)
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I installed Windows on my computer, followed by an installation of Ubuntu. However, now I'm unable to boot into my Windows install. What can I do to fix this?
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Human beings have evolved from their ancestors to their modern forms adapting many changes in structure and I would assume that every change has a significance. So, what is the cause of our hair turning white at old age? Was it meant for frightening away predators at old age when our body is weak? Or what is it actually?
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A vast majority of humans get at least some grey hair as they age. As far as I know this applies to both genders and all races. Presumably this means that at least some grey haired humans have noticeable reproductive advantage, or maybe they had it in the recent past. Theoretically, because this feature is so prevalent, there must be a strong evolutionary pressure to keep it. Am I right? If so, what is it?
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I'm new to Latex and I was wondering if it is possible to look up the documentation of tex packages in the terminal like with man pages? I find myself frequently having to look up stuff online that I think is very basic, like for the titlepage environment. I would ideally love to have a "man" page for this open while working on the document. Any help is appreciated.
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Where could I find the Tikz Manual version 3.0.1a as a PDF file ? More generally, how do I find the documentation for a package.
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While saving the information to the database field the settings were as follows: character set: latin1 collation: latin1_swedish_ci Once the users updated the information,i noticed that many information were saved as "?????????????? ??????????????? ???? ?????" (Question marks) to the database. English(language) information were saved without questions marks. All other languages were saved with question marks. Now i have changed the character set to utf8 and all the languages are saved properly. The problem is that i need to recover the information which is saved as question marks. eg:"?????????????? ??????????????? ???? ?????" XAMPP Version: 5.6.19 Navicat version 11.0.17 Database server Server version: 10.1.10-MariaDB - mariadb.org binary distribution Web server Apache/2.4.17 (Win32) OpenSSL/1.0.2d PHP/5.6.19 PHP version: 5.6.19 phpMyAdmin Version information: 4.5.1 Please help me to get the original data.
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I'm setting up a new server and want to support UTF-8 fully in my web application. I have tried this in the past on existing servers and always seem to end up having to fall back to ISO-8859-1. Where exactly do I need to set the encoding/charsets? I'm aware that I need to configure Apache, MySQL, and PHP to do this — is there some standard checklist I can follow, or perhaps troubleshoot where the mismatches occur? This is for a new Linux server, running MySQL 5, PHP, 5 and Apache 2.
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I can see why there is only one element in $GF(p) \setminus \{0\}$ of order 2. But I'm not sure why I can claim that this would be the same element and only element for $GF(p^r)$.
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In field of characteristic $p$, where $p$ is prime, why can $x^2=1$ only have the two solutions $1$ and $-1$? Is it just because that polynomial only has degree 2?
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Alice and Bob want to agree on a bit $0$ or $1$. Both know it would be fair to pick that at random, but there's no way they could meet to throw a dice and no third party they could trust. Are there known protocols that allow either side to prove that they did not manipulate the outcome? My idea is: Both randomly (or not - but that would be in their best interest) pick $0$ or $1$, write it down, put it in an envelope and send it to the other person. Then the XOR of both bits could not have been manipulated unfairly by either party. The problem I see with that: How can Alice prove to Bob that she did not open his envolope before making her choice? Maybe one could instead choose an initial string $n$ and use the first $k$ with $f^k(n) < a$ as the chosen value. Now if $f$ is a cryptographic hashing function and $a$ is small Alice would have taken a long time if she were to predict $k$ before sending her own choice.
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Several people are playing a game with random events and require a way to produce a random number. (Such as dice rolls or a lottery.) Can this be done such that each player has the power to be reasonably sure that the random number was fairly selected, without having to trust anyone else? This question stems from a discussion in comments to my answer on the . I came up with a protocol but someone else spotted a flaw. This site seems more appropriate. Please feel free to make use of my answer to that question.
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My project is in codeigniter, i am sending mails in it with following code snippet, its working fine, just problem is that mail are going into spam folder of users, why this is happening, please suggest me the changes in following code snippet. My Code Snippet: $subject = 'Test Subject'; $config['protocol'] = 'smtp'; $config['smtp_host'] = "localhost"; $config['smtp_port'] = "25"; $config['charset'] = 'utf-8'; $config['wordwrap'] = TRUE; $config['mailtype'] = 'html'; $config['bcc_batch_mode'] = TRUE; $config['crlf'] = '\r\n'; $config['newline'] = '\r\n'; $this->email->initialize($config); $this -> load -> library('email'); $msg = "Test Message"; $this -> email -> from('[email protected]','Domain Name'); $this -> email -> to('[email protected]'); $this -> email -> subject($subject); $this -> email -> message($msg); $this -> email -> send(); What is settings to prevent mail from spam folders??
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This is a tricky one and I've always relied on techniques, such as permission-based emails (i.e. only sending to people you have permission to send to) and not using blatantly spamish terminology. Of late, some of the emails I send out programmatically have started being shuffled into people's spam folder automatically and I'm wondering what I can do about it. This is despite the fact that these particular emails are not ones that humans would mark as spam, specifically, they are emails that contain license keys that people have paid good money for, so I don't think they're going to consider them spam I figure this is a big topic in which I am essentially an ignorant simpleton.
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I have signed up for SO using my google account and have also used Facebook to sign in too. But due to some change in policies my company has decided to block Google accounts(only search is available) and Facebook. How can I log into my same SO account without Google Sign In? Can I use OpenID and how?
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I no longer use the service that I originally used to register, and would like to change the service I use to log in, or at least add a second account. Is this possible? How do I change my login provider or associate a backup method to log in? For more information, see "" in the .
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Each Stack Exchange site has the same kind of style. How are these styles maintained in a uniform fashion? Is there some sort of base template that each site shares and overrides as necessary? And similarly, how does each site implement the notification system? Is each site responsible for implementing it, or is there an underlying framework that is utilized? I'm gearing up to implement a system that has base functionality shared across multiple sites, so I'm very interested to hear how it's been done before.
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What tools and technologies are used to build the Stack Exchange Network? See also:
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In running an ad campaign through a DSP, we get clicks and CTR as a measure of performance, from the ads to the landing page or advertiser website. How do these clicks that our DSP reports, correlate to the amount of users/sessions/visits that the advertiser sees in their Google analytics platform for their website? and why are there usually large discrepancies?
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After a month of ads with Google Ads Shopping campaigns and continuously identifying, day after day, a significant discrepancy of clicks on Google Ads and Sessions in Google Analytics (as well as another analytics tool that brings numbers very close to analytics's numbers), I contacted Google Support. For more than 3 weeks, after numerous interactions and different/contradictory suggestions/explanations/solutions, it finally seems that my case has taken a direction towards the solution, but the result that has been passed to me, despite having convinced me that it is the which may actually be the cause of the problem, was not satisfactory to me. I was really disappointed with the procedure Google Support provided me, and would like more explanations and information from the community. What I got last through Google's support was this: "There are two methods for logging out of a session: a session can be opened on the same day or on several days, weeks or months. Expiration by time: After 30 minutes of inactivity At midnight Campaign Change: If a user enters through a campaign, he leaves and then comes back through another campaign. Why is there a discrepancy between clicks and sessions? I have separated this from the help center that explains specifically what we said in connection If you've noticed one of the following discrepancies between clicks and sessions, use the to identify and resolve issues. As well as reporting the discrepancy between clicks and sessions up to 20% is considerable. " Among the Google help links passed by the support, it has not been clear to me whether a 20% less discrepancy in the number of sessions in relation to clicks is normal or if only when the session number is higher (the phrase "A single user can open multiple sessions" suggests that it is only normal when the number of sessions is higher). But if it's really normal that the number of sessions is 20% less than the number of clicks, I'm led to think of the possibilities: 1 - Analytics fails as a tool to count 100% the number of sessions (accessed by the same person or by different people). Once when a click occurs, the user is taken to the site and must count as a session. If it is normal for analytics to compute 20% fewer sessions than clicks, soon the analytics fail to compute all the sessions. 2 - Google uses this explanation to be able to charge up to 20% more clicks than clicks that actually occurred from its users. I do not like to believe in either hypothesis, first to rely on Google Analytics as a tool to identify sessions and because their numbers are very similar to that of a third analysis tool used (built by my ecommerce platform), and also for not believing that a company like Google would lend itself to deliberately charging 20% more clicks from its customers. So I turn to the community so maybe someone will bring me a third alternative that I have not been able to identify and/or a totally different explanation from the one I received from the support (as they have done so many times over the course of those weeks).
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My code currently filling up a HashSet with an object of Class Coin. private HashSet<Coin> walletcoin; public Wallet(int WalletSize) { walletcoin = new HashSet<Coin>(); for(int i = 0; i < WalletSize; i++){ walletcoin.add(new Coin()); } } This seems to be working fine. Class Coin: public class Coin { public Coin(){ } } The second method is currently trying to remove a Coin object from the HashSet. public int removeCoin() { Coin toremove = new Coin(); if(walletcoin.contains(toremove)) { if(walletcoin.remove(toremove)) { return 1; } } return 7; } I have created a new object of Class coin, to try to search against the HashSet. Currently after testing the program skips straight to the final return statement and does not go through the if statements. How would I be able to modify my code in order for the if statements to correctly work, and remove one of the type Coin elements from the HashSet.
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What issues / pitfalls must be considered when overriding equals and hashCode?
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I want to use TestNg in my learning project. While using TestNg framework, i am getting NullPointer Excetion. I think problem is in WebDriver object declaration part. But i don't know how i can implement the same. Can any one help me on the same? Please find the code below, package in.prolearn.testcases; import java.util.concurrent.TimeUnit; import org.openqa.selenium.WebDriver; import org.testng.annotations.BeforeMethod; import org.testng.annotations.BeforeTest; import org.testng.annotations.Test; import in.prolearn.pages.HomePage; import in.prolearn.pages.SearchResultPage; import in.prolearn.utility.BrowserSelection; public class VerifySnapDealSelection { WebDriver driver = null; @BeforeTest public void preCondition(){ driver = BrowserSelection.browserSelection("Chrome"); BrowserSelection.openBrowser("https://www.snapdeal.com/"); } HomePage hp = new HomePage(driver); SearchResultPage srp = new SearchResultPage(driver); @Test public void NavigateToSearchCategoryPage() throws InterruptedException{ hp.menuSelectionGeneric("Computers & Gaming"); Thread.sleep(5000); hp.subMenuSelectionGeneric("External Hard Drives"); Thread.sleep(5000); } @Test public void SearchResultPageValidation() throws InterruptedException{ srp.FirstcapacitySelection("1 TB"); Thread.sleep(5000); driver.manage().timeouts().implicitlyWait(20, TimeUnit.SECONDS); srp.FirstcapacitySelection("2 TB"); Thread.sleep(5000); srp.verifySelectedItem("1 TB"); srp.verifySelectedItem("2 TB"); Thread.sleep(5000); srp.DeleteSelectedItem("2 TB"); Thread.sleep(5000); srp.VerifycapacitySelection("2 TB", "false"); srp.VerifyItem("1 TB", "1TB"); srp.DeleteSelectedItem("1 TB"); Thread.sleep(5000); srp.VerifycapacitySelection("1 TB", "false"); } }
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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?
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I am stuck at this problem for long time: Prove that if $f:\mathbb{R}\to\mathbb{R}$ is some real-valued function, Then $|f(\mathbb{N})|\leq\aleph_0$. In other words, prove that there exists a one-to-one function from $f(\mathbb{N})=\{f(n)|n\in\mathbb{N}\}$ to $\mathbb{N}$. If $f(\mathbb{N})$ is finite then it is clear that $|f(\mathbb{N})|\leq\aleph_0$, But if $f(\mathbb{N})$ is infinite then I got stuck. Thanks for any hint/help.
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Hi everyone I'd like to know if the following reasoning is correct, any suggestion would be great. Thanks. Proposition: Let $Y$ be a set and let $f: \mathbb{N}\rightarrow Y$ be a function. Then $f[\mathbb{N}]$ is at most countable. Proof: If $Y$ is finite the result follows, this is because$f[\mathbb{N}]\subset Y$ and any subset of a finite set is finite and has at most the size of the set in which is contained. We may assume that the set $Y$ is infinite. We set $A:= \{\,n\in\mathbb{N}:f(i)\not=f(n) \,\,\text{ for any }i< n\, \}$. And we define the function $g:A \rightarrow f[\mathbb{N}]$ as the restriction of $f$ in $A$. We claim that the function $g$ is a bijective map. From the definition of $A$ we already know that the map is $1:1$. We will show that also is onto. Let $y\in f[\mathbb{N}]$. Suppose for the sake of contradiction that there is no $n\in A$ such that $g(n)=y$. Since $y$ lies in the image of $f$, then there is some $j\in \mathbb{N}$ for which $y=f(j)$. Then either $f(j)\not= f(i)$ for any $i<j$ or there exists some $i<j$ such that $f(j)= f(i)$. For the former, $j$ lies in $A$ (by its definition). For the latter, the set $\{\, n\in \mathbb{N}: f(j)=f(n)\, \text{and }\,n\not=j \}$ is non empty, and hence has a minimum element. Let $m$ be its minimum element. Then $f(m)\not=f(n)$ for any $n<m$ and thus $\,m\in A$ but $g(m)=f(m)= f(j)=y$. Thus any case leads to a contradiction. The result follows by reductio ad absurdum. Hence $f$ is surjective and injective, i.e., a bijective map. Since there is a bijection between $A$ and the images of the natural numbers under $f$, both have the same cardinality. Also we already know that $A\subset \mathbb{N}$ and any set of the natural numbers is denumerable, thus $f[\mathbb{N}]$ is countable. $\Box$
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I am making an adventure world that is players versus monsters. I understand adventure mode doesn't allow players to break blocks, but not monsters. I would like to keep creepers, but it seems to do this I would have to build every thing out of obsidian and bedrock so the creeper explosions don't ruin my paths and rooms! So, what command might be used to make every block in the world unbreakable instead?
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Please note that these are NOT acceptable solutions: Completely disabling monsters (peaceful mode) Completely removing creepers Completely disabling explosions (TNT + Creepers) Disabling creeper explosions More exactly, I want the creepers to be able to spawn and explode, but without doing their terrain damage (they should still be doing health damage to the players). I'm fine with the use of mods but I'd prefer a built-in solution if possible.
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Why an open tube at both ends suffers resonance when subjected to a sound that propagates through the air with length of where $L / 2$? I already know the methodology to calculate the harmonics in an open tube. So, I'm not expecting an answer that is based on the calculations. I want to know why this phenomenon occurs from the molecular point of view of the air, taking into account that air could be considered as an ideal gas whose molecules have no interaction with each other.
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How can standing waves be produced in an open organ pipe even though both of its ends are open? Can someone explain with more clarity?
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I want to create a systemd service that starts N identical copies of a process (as in, same arguments for each copy), and restarts any of them if they crash. It is okay if N is hardcoded in the service file. Google suggests that templated/instantiated services can do this, but the examples I find are all of the form systemctl start myservice@someid, repeated for each process, which is not what I want. I want to be able to do systemctl start myservice and have it start all processes and keep them alive. How do I do this correctly? (I am porting this service from upstart, which requires two files to achieve this effect, one parent instantiating multiple children. That would be okay, albeit not ideal)
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At my organization, we have a number of queue consuming worker processes. We're currently using SupervisorD to manage them, but would like to use SystemD if possible for certain advantages therein. I'm fairly experienced with writing custom units, but I don't immediately have an analog in SystemD land for this. In the a parameter called numprocs is detailed which allows one to set the number of processes they'd like to be started with the service. If I want 30 processes started, it's a one-line change. Is there a setting in SystemD units that will allow me to specify how many of these processes I'd like started?
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I found the titular question Let $A$ be a $10\times 10$ matrix and $A^{10,000} = 0$. Show $A^{10} = 0$ On a practice qualifier. I am very rusty on linear algebra and could not remember any specific theories other than maybe finding the characteristic polynomial of $A^{10}$ and reasoning that if it is not equal to the $\lambda^{10}$ then the characteristic polynomial of $A^{10,000}$ is certainly not equal to $\lambda^{10,000}$ but drew a blank when trying to rationalize why this would be so and why it would matter. So maybe that is a dead end. Then I saw this post which included many unique ways of solving that (possibly similar) question. So what are some possible proofs for this question? Ideally I would start completely reviewing linear-algebra but I am catching up on a lot of subjects and won't have the time to dive deep into it until the summer. In the mean time I'd like to do a little targeting refreshing on practice qualifiers like this one. Thank you for any help! p.s. I included an abstract algebra tag because that is where I have the strongest background so feel free to use generalized theorems and techniques from abstract algebra along with any linear-algebra proofs you like.
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I want to use the fact that for a $(n \times n)$ nilpotent matrix $A$, we have that $A^n=0$, but we haven't yet introduced the minimal polynomials -if we had, I know how to prove this. The definition for a nilpotent matrix is that there exists some $k\in \mathbb{N}$ such that $A^k=0$. Any ideas?
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While developing a React app, I needed to use some environment variables. The way to do it is by using this syntax: REACT_APP_NOT_SECRET_CODE=abcdef npm start My first question is: How does that work? I don't know this linux thing, what's happening behind the scenes? My second question is: How to I make more scalable? say I have file that looks like that MY_VAR_1=123 MY_VAR_2=23332 MY_VAR_3=3232 How do I inject it to the npm process? I tried cat .env | npm start But it doesn't work I guess after I understand the linux syntax I get be in a better position to use a file instead of inline data. Thanks
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When I run this command: https_proxy=http://myproxy.com/ aws [aws-param] the proxy is picked up by the aws command line tool. However - when I do this: https_proxy=http://myproxy.com/ aws [aws-param] the aws command doesn't pick up the proxy. To me, they're the same from a unix point of view. Is this something about the way python reads environment variables? My question is: Why does an inline variable definition work but a previous line does not for an aws command?
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The spell description states: For the duration, you sense the presence of magic within 30 feet of you. If you sense magic in this way, you can use your action to see a faint aura around any visible creature or object in the area that bears magic, and you learn its school of magic, if any. In question it is said that detect magic can reveal the presence of a sorcerer. What about other classes, like clerics (whose magic has a divine origin), or wizards?
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Inspired by a recent question about discerning divine and arcane spellcasters, of like to hear the case for and against detecting spellcasters of either style with . I think you can detect whether someone has prepared spells, based on this language: For the duration, you sense the presence of magic within 30 feet of you. If you sense magic in this way, you can use your action to see a faint aura around any visible creature or object in the area that bears magic, and you learn its school of magic, if any. (emphasis mine) Preparing spells is described as having the spell "fixed in mind" (). I'd argue that qualifies as bearing magic, and opens the door to using detect magic to identify spellcasters with currently prepared spells. What do you think?
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Can anyone tell what of kind of insect is in this image ? They have been showing up in my room for the past month; never happened before that. The room is generally hot during daytime. Thanks
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I have been seeing them more and more frequently indoors. I am currently in the Midwest United States, weather has been unusually warm for December, and there are many trees nearby. Can someone please help identify this? The pictures are of the same bug, but from different angles.
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I need to reinstall 18.04 (due to ongoing problems) and was wondering as to the best way to partition. I have a 1TB HD. I want a separate /home directory so I was wondering what's the best way to go about it to allow enough space for /boot, /, etc.? Right now my /home directory is 173.8 GB. Can I let Ubuntu take care of the other sizes when I get to the "Something Else" screen? EDIT: I don't believe the question is a copy as I would have skipped that answer in a search as it also deals with Windoze.
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This is not a question on or but is a question on access rights and how not to let them bite you in the lower abdomen... ;-) This question will not help you how to make partitions on your disk, but will tell you what to do in , depending on your personal use case, so choose one of the following: Note: The above questions can also be used with multiple disks, but the examples in the answers are given for one disk.
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a) Given a set $S$ with the $n$ elements, find the number of ordered pairs $(A,B)$ such that i) $A \subseteq B \subseteq S$ ii) $A \subset B \subseteq S$ b) Let n be a positive integer and S a set of size n. How many relations $\approx$ on S are there that are: i. an equivalence relation and a partial ordering? ii. an equivalence relation and a total ordering? Normally the topic that I ask about I have a general understanding of (Calculus) but I am having a really tough time with Discrete Maths... Any idea what I should do here?
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Find total number of relations that are equivalence as well as partial order set. Assume set contains total $n$ elements. My attempt: As equivalence relation has property reflexive, symmetric and transitive and POSET has property reflexive, antisymmetric and transitive. Symmetric and antisymmetric will cancle each other except reflexive relation and transitive relation can case antisymmetric, so it's also absent on resultant relation. Therefore, all diagonal element should be present to satisfy conditions of equivalence as well as POSET. So, it's independent of number of total number of element of set and answer will be $1$. Can you explain in formal way, please?
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Is "The crowd are loving this." acceptable grammar? I think it should be "The crowd is loving this." Does it matter if it's a UK newspaper?
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I'd say Microsoft have a way of bending the rules and I know that McLaren have won the championship. While this sounds strange, I believe it is correct English (sorry, I'm not native). But when it's a small company, would you still use it this way? Is a company always plural, or are small companies singular? I.e., would you say Bakery Johnson makes fine bread or Bakery Johnson make fine bread? Is it My book seller, Woody's, have moved or is it has moved?
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I just downloaded ubuntu to my Dell laptop and I'm about 6 hrs new to this system. On my girlfriends windows 7 laptop I burnt the movie frozen to a dvd-rw and put it in the xbox, ps4, and a portable dvd player but none of them worked. Since I am new to this ubuntu I am wondering what type of programs will I need and how can burn working movies to a dvd-rw that works in most movie players like xbox, ps4, or most dvd players.
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I have several .dvd files which were created using . To export the videos from OpenShot, I used the DV-NTSC widescreen and DV-PAL Widescreen property. Can anyone tell me how I can burn these *.dvd files into a DVD that can be played with my external Sony CD/DVD 5.1 Player which is connected to a TV?
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How does a white hole form in nature if it were to exist? No knowledge of general relativity or advanced mathematics but doing a researching a physics project and need a basic explanation.
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How do form? Why are they called the "time-reversed" versions of a black hole? What's an "eternal" black hole? How come a white hole is only encountered if you remove the star from the space-time surrounding the black hole? Why is it that if you add any matter to the area that the white hole disappears? Any explanation greatly appreciated.
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Is has been established that Logan . And, as can be seen from the trailers and , it takes place in desert terrain in Oklahoma, Texas, and Mexico. So most things are old and dusty. But, for example, the cars and objects in the gas station store don't appear to have been modified to appear to be from our future. Besides the obviously sci-fi elements (cybernetic mutants and their weapons, for example, which in the X-Men universe are not necessarily futuristic) is there anything else that would indicate that this is 12 years into the future? Edit: Follow on question:
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This is a follow up to Logan in Mexico, Texas, Oklahoma and other wilderness locations. Besides the obviously sci-fi elements (cybernetic mutants and their weapons, medical technology, etc, for example, which in the X-Men universe are not necessarily futuristic) what else is there in the appearance of film that would indicate that this is 12 years into the future? This is a question about -- the appearance of things, people, and settings, indepedent of the story elements. I.e. we agree it takes place in the future; the question is about what visual elements there are that were influenced by that story element -- and, for the purpose of this question, that are different than present day real-world things.
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This is a math question I'm supposed to do, I know the limit does not exist(it's mentioned in the question) but I can't find any 2 paths that gives me any other answer than 0. Please if you can answer this, help me out Thanks
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I'm trying to find $2$ paths through $(0,0)$ to show that $\lim_{(x,y) \to (0,0)}\dfrac{xy^2}{x^2 + y^4}$ does not exist. I only manage to use path $y=x$ but can't find second one. Any thoughts on which path to choose to show that this limit doesn't exist? Thanks!
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I'm studying the following circuit The image is explicit but as you can see the input measured in the upper terminal is a square wave with \$E_c\$ and \$-E_c\$ as levels. Now I also had no trouble understanding that if \$R_B \leq \beta R_C\$ when the square wave is in the positive half-cycle we have saturation and when it is on the negative half-cycle we have cutoff situation. Now in saturation we will (because the junction voltages are zero) an output voltage of zero. That is correct with the figure. However when we are in cutoff, applying KVL to the output mesh leads us to $$U_{CE}=-E_c$$ because currents can be neglected. That however is not concordant with the figure which shows $$U_{CE}=E_c$$ Why is that? What am I missing?
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I'm studying the following circuit The image is explicit but as you can see the input measured in the upper terminal is a square wave with \$E_c\$ and \$-E_c\$ as levels. Now I also had no trouble understanding that if \$R_B \leq \beta R_C\$ when the square wave is in the positive half-cycle we have saturation and when it is on the negative half-cycle we have cutoff situation. Now in saturation we will (because the junction voltages are zero) an output voltage of zero. That is correct with the figure. However when we are in cutoff, applying KVL to the output mesh leads us to $$U_{CE}=-E_c$$ because currents can be neglected. That however is not concordant with the figure which shows $$U_{CE}=E_c$$ Why is that? What am I missing?
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I'm working on a project. We have two balloons, connected by a hose with a valve.We know when we open the valve, by according to internal pressure of each balloon, air goes form the higher pressure balloon to lower pressure balloon. I want to know the relation between internal pressure of the balloons and the flow rate between these two balloons. Pay attention, I don't want the air transfer direction, I want the FLOW RATE. Thanks.
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Last day , when i was working on two interconnected balloons , a question was kicking my brains !!! This is the explanation of the question: First , suppose a system that composed of two spherical membranes filled with air (two balloons have different initial volumes {means that the pressure inside which balloons are different} and the air pressure is 1 a.t.m) . We connect them with hollow tube and a valve. When we open the valve , one of them shrinks and the other one expands (It depends on their pressure) . So how can we get the velocity of the flowing air between two balloons? (Consider everything but if you have reasons for not considering one of them -for example the ratio of friction in the tube- Don't consider them and just tell me the reason) Thanks
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This paradox is very common it seems, in which A sees B's clock running slow and B sees A's clock running slow. Here is the question a little more concretely. Let's say B flies by A's spaceship. If B's clock advances $t$, then in that time A's clock advances $\gamma t$ through time dilation (This is easily shown if there is a light clock next to B). Now from A's perspective (assume there is a light clock next to A), during that same time interval, he sees B's clock run slower and thus this time interval must be $\gamma^2 t$. Equating the time intervals gives $t = \gamma^2 t$ and $\gamma = 1$, which is clearly wrong. How is this reconciled?
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I read a lot about the classical twin paradox recently. What confuses me is that some authors claim that it can be resolved within , others say that you need . Now, what is true (and why)?
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I have a device with an input rating of 23 to 56V DC with a maximum current of 0.5 amperes. Is it possible to supply this device with a power supply with an output rating of 48V DC with 1.0 ampere?
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Power supplies are available in a wide range of voltage and current ratings. If I have a device that has specific voltage and current ratings, how do those relate to the power ratings I need to specify? What if I don't know the device's specs, but am replacing a previous power supply with particular ratings? Is it OK to go lower voltage, or should it always be higher? What about current? I don't want a 10 A supply to damage my 1 A device.
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I would like to use both insert and remove in the same sentence. However, I would like to know how I will use the prepositions because the verbs have different prepositions into/from. There are some posts about this issue; however, mine is a little bit different because there is an object after my verbs as seen below. This method either inserts or removes some parameters from queries. What is the correct way of writing this sentence? I am not sure because both insert and remove needs some parameters. This method either inserts into or removes some parameters from queries. I think the above does not sound well, or This method either inserts or removes some parameters into or from queries. Thanks
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Examples: Data can be imported to and exported from the application. Data can be imported and exported from the application. Data can be imported to the application and exported from it. The manager defined the products that should be added to and removed from the store. The manager defined the products that should be added and removed from the store. The manager defined the products that should be added to the store and removed from it. I assume that the third sentence is correct in my examples. My question is whether the two other sentences are correct.
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What is the difference between Math.Floor() and Math.Truncate() in .NET? e.g. Math.Floor(5.4) = 5 Math.Truncate(5.4) = 5 – subramani
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What is the difference between and in .NET?
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I came across the phrase absent fraud in I searched for its meaning on Google but didn't find anything. What does absent fraud mean? I can’t help but empathize with an employee being fired and will ask multiple questions before any termination. Was there one bad act or a series? Did they have feedback and a chance to change? Was it performance or personality? Absent fraud or transgression, is there a different job in the organization the employee could succeed at? How do we tell them and what, if any, severance is offered? What help can we offer in finding another job more suited to their skills? How can we preserve their dignity?
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In the following sentence of today’s Time magazine’s article titled "Obama's Afghanistan problem: Neither Karzai nor the Taliban like the 'Reconciliation' Script," the word absent appears to be used as a preposition having the sense of ‘without.’ “Karzai's independent power base is minimal, as is his ability to influence the outcome of his country's civil war absent direct U.S. involvement. And that gives neither Karzai nor the Taliban much incentive to cut a deal with the other.” As I don’t think I’ve seen case ‘absent’ being used in this way, I consulted OALD. It defines ‘absent’ only as a noun and verb. The Cambridge online dictionary also defines it as an adjective meaning ‘not in the place where you are expected to be, especially at school or work.’ Is it natural to use ‘absent’ as a preposition as used above? For example, would you casually say ‘It won’t go well absent your help’ in your daily conversation? Is it the same with the usage pattern of ‘short of’?
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Let $f:\mathbb{R} \rightarrow \mathbb{R}$ be a function such that $f(x+y)=f(x)+f(y)$. If $f$ is continuous at zero how can I prove that is continuous in $\mathbb{R}$.
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The asks about functions $f \colon \mathbb R \to \mathbb R$ such that $$f(x+y)=f(x)+f(y).$$ It is a very well-known functional equation, which appears in various areas of mathematics ranging from exercises in freshman classes to constructing useful counterexamples for some advanced questions. Solutions of this equation are often called . Also a few other equations related to this equation are often studied. (Equations which can be easily transformed to Cauchy functional equation or can be solved by using similar methods.) Is there some overview of basic facts about Cauchy equation and related functional equations - preferably available online?
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Let $k > 2$ be an integer. Is there a finite non-abelian group with exactly $k$ conjugacy classes? The only group with $1$ conjugacy class is the trivial group, and the only group with exactly $2$ conjugacy classes is the group of order $2$, so the restriction $k>2$ is necessary. (The symmetric group $S_3$ has $3$ conjugacy classes, and is the only such non-abelian group.) For small values of $k$, the number of non-abelian groups with exactly $k$ conjugacy classes are . I had originally come to this question for square-free values of $k$, but upon thinking about it, I realised that there was an even more basic form of the question, whose answer I did not know and could not find, as stated above. I thought that it might be possible to construct a group of the form $G = A\rtimes B$, with $A$ abelian of order $k$, and $B\leq\operatorname{Aut}(A)$ so that $G$ has exactly $k$ conjugacy classes, but I was unable to come up with a general argument. It does not always work for cyclic $A\cong C_k$.
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Given an integer $n\geq 1$, it is known that there are only finitely many finite groups with exactly $n$ conjugacy classes. Question: For $n\geq 3$, does there exists a finite non-abelian group, with exactly $n$ conjugacy classes?
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Well, I was wondering about the real age of our universe, I found that it's estimated to be $13.8\times 10^9$ years. Is it an approximation, or laws behind this age?
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Many times I have read statements like, "the age of the universe is 14 billion years" . For example this wikipedia page . Now, my question is, which observers' are these time intervals? According to whom 14 billion years?
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I got a shiny Rayquaza over Wondertrade. I noticed it didn't have the blue pentagon next to it. I've been told that's the sign of a hacked pokemon. Will it hurt my game in anyway because I have it?
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On the Pokemon status screen, underneath the Pokemon and to the left of the custom markings, is a small blue pentagon: This doesn't seem to be present on Pokemon obtained through the Pokemon Transporter from Gen V: I've looked into it myself, and popular opinion seems to be that it's either some kind of "Legitimate Pokemon" mark or simply to indicate that the Pokemon originates from Gen VI. The latter seems far more likely to me, but do we know for sure what this blue hexagon means?
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If $G, H$ are groups and $G$ is isomorphic to $H$, prove the following: If $G$ has an element of order $n$, then $H$ has an element of order $n$, and If each element of $G$ has finite order, then each element of $H$ has finite order. For both, isn't there a theorem that states the exact thing? If this is straight definition, what am I suppose to prove?
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Let's say $f$ is an isomorphism $f:G \rightarrow G'$, where $G$ and $G'$ are multiplicative groups. Then for $x\in G$, if $f(x) = x' \in G'$. Do we have always have $\text{ord}(x) = \text{ord}(x')$? Why?
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In this code i have implemented My own list model AbstractListModel to be able to add and remove elements to list adding works removing also, but i want here the elements to be added and removed like this: "add John", John is added to the list, same with removing. I splited string by delimeter and added it to my array of strings but it does not work, so here is my question how to add elements and remove by the delimeter. import java.awt.*; import java.util.*; import javax.swing.*; class MyListModel extends AbstractListModel<String> { ArrayList<String> list = new ArrayList<>(); public int getSize() { return list.size(); } public String getElementAt(int index) { return list.get(index); } public int getIndexOfItem(String searchTerm) { int z = 0; for (int i=0;i < list.size();i++) { if (list.get(i).equals(searchTerm)){ z = i; } } return z; } public void add(String item) { list.add(item); fireIntervalAdded(this, list.size() - 1, list.size() - 1); } public boolean remove(String name) { boolean success = false; int size = list.size(); for (int i=0;i < size;i++) { if (this.getElementAt(i).equals(name)) { this.remove(i); size--; success = true; } } return success; } public void remove(int index) { list.remove(index); fireIntervalRemoved(this, index, index); } public boolean isEmpty() { boolean empty = false; if (this.getSize() == 0) { empty = true; } return empty; } } public class JListl extends JFrame { public JListl() { MyListModel ml = new MyListModel(); JList list = new JList(ml); add(new JScrollPane(list)); TextField tf = new TextField(); add(tf, BorderLayout.SOUTH); this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); this.setTitle("JList Renderer Example"); this.setSize(250, 400); this.setLocationRelativeTo(null); this.setVisible(true); tf.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent e) { //here is the problem String[] a = tf.getText().split("\\s+"); // ml.add(a[1]); if(a[0]=="add"){ tf.setSelectionStart(4); tf.setSelectionEnd(a[1].length()); ml.add(a[1]); System.out.println(a[1]); }else if(a[0]=="del"){ ml.remove(a[1]); } } }); } public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { @Override public void run() { new JListl(); } }); } }
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I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug. Is == bad? When should it and should it not be used? What's the difference?
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Let $b>a>0$ and $f$ continuous. Prove that $$\lim_{\varepsilon\to 0^+}\int_{a\varepsilon}^{b\varepsilon}\dfrac{f(x)}{x}\ \text{d}x=f(0)\ln(b/a).$$ My Try. Solving the integral by parts. Let $u=f(x)$ and $dv=1/x\ dx$. Then, $du=f'(x)dx$ and $v=\ln x$. So, $$\begin{align*} \lim_{\varepsilon\to 0^+}\int_{a\varepsilon}^{b\varepsilon}\dfrac{f(x)}{x}\ \text{d}x&=\lim_{\varepsilon\to 0^+}(f(x)\ln x|_{a\varepsilon}^{b\varepsilon}-\int_{a\varepsilon}^{b\varepsilon}f'(x)\ln x\ \text{d}x)\\ &=\lim_{\varepsilon\to 0^+}(f(b\epsilon)ln(b\epsilon)-f(a\epsilon)\ln(a\epsilon))-\lim_{\epsilon\to 0^+}\int_{a\varepsilon}^{b\varepsilon}f'(x)\ln x\ \text{d}x\\ &=f(0)\ln(b/a)-\lim_{\epsilon\to 0^+}\int_{a\varepsilon}^{b\varepsilon}f'(x)\ln x\ \text{d}x.\end{align*}$$ and there in that last part I got stuck. How can I prove that the integral that remains is 0 or remove it from there?
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Let $f:[0, 1] \rightarrow \mathbb{R}$ a continuous function. If $a>0$, show that: $$ f(0)\ln(\frac{b}{a})=\lim_{\epsilon\rightarrow 0}\int_{\epsilon a}^{\epsilon b} \frac{f(x)}{x}dx$$ Tried using Riemann sum, but did not succeed.
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I was wondering on where the origins of the word tar to mean thank you came from. I have reached tar and have come up with this definition Tar is a dark brown or black viscous liquid of hydrocarbons and free carbon, obtained from a wide variety of organic materials through destructive distillation. How does this relate to being thankful?
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Where does the expression "ta" come from? Wikipedia has only to say: "ta!", slang, Exclam. Thank you! {Informal}, an expression of gratitude but no additional information or links about its genesis. I have only ever heard it from englishmen and -women. Is it used anywhere else in the world? How did it come about? What is its history?
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Lets say that I have 3,200 observations that I want to use for training a neural network model, and I want to set the batch size to 32. The number of minibatches used in every epoch for updating the weights is therefore 100. How will my data be divided during minibatching? Assuming I have datapoints $x_{1}, x_{2}, ... , x_{3200}$ - will minibatch slice the data as it is, and use the same slices in every epoch? e.g. $$ Epoch 1: minibatch1: [x_{1}, x_{2}, ... , x_{32}], minibatch2: [x_{33}, x_{34}, ... , x_{64}] \\ Epoch 2: minibatch1: [x_{1}, x_{2}, ... , x_{32}], minibatch2: [x_{33}, x_{34}, ... , x_{64}]\\ Epoch 40: minibatch1: [x_{1}, x_{2}, ... , x_{32}], minibatch2: [x_{33}, x_{34}, ... , x_{64}] $$ Or are the slices shuffled in every epoch, such that there are different combinations of observations in every minibatch in every training epoch? e.g. $$ Epoch 1: minibatch1: [x_{67}, x_{2891}, ... , x_{930}], minibatch2: [x_{102}, x_{7}, ... , x_{1241}] \\ Epoch 2: minibatch1: [x_{3174}, x_{15}, ... , x_{412}], minibatch2: [x_{753}, x_{2447}, ... , x_{1630}]\\ Epoch 40: minibatch1: [x_{456}, x_{73}, ... , x_{1984}], minibatch2: [x_{29}, x_{675}, ... , x_{2354}] $$
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I saw some related question regarding to the fact is one should use sampling with resampling or without when using minibatch. However my question is different. Let's assume that I use sampling witouth replacement. Meaning that for each epoch one training example can only belong one 'batch size' group. I want to know if one should only resample the training data (into the different batch size) only 1 time or before to start to update the parameters before each epoch. For instance suppose I have 20 'batch size' group. Suppose at the first iteration I have sampled picture A in group 2 and picture B in group 4. If so should picture A always stay in group 2 and picture B in group 4. Or should I resample it before to start a new epoch (e.g. at epoch 2 put picture B in group 6 and picture B in group 20).
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I just downloaded the media9.zip package and unzipped it to a subdirectory of C:\texlive. But I don't know where to go from here. The documentation says: "MiKTeX and TeXLive users should run the package manager for installation", but I don't see anything in the folder tree with names resembling 'package manager' or 'installation'.
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I need to install a new TeX/LaTeX/ConTeXt package on my computer. I'm running Ubuntu/Fedora/Slackware/Some-Version-Of Linux. What are the possible ways to do this? Note: We get a number of questions that essentially reduce to this one; it was felt a good idea to have one question-and-answer that can cover all the standard methods. See for the discussion. The question-and-answer are CW so that more information can be easily added. If you have information to add, please do so. If you are unsure, leave a comment here or (preferably) in . Comments on the question and answer will be periodically removed to ensure that the information is clear.
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My use case guarantees that all plaintext values are unique. In this case, is it safe to use a fixed IV with AES-GCM to carry our encryption/decryption?
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I understand that initialization vectors (IV) should not be used twice when using AES/GCM. I am using a counter as an initialization vector. Every time I send out a new packet (I am developing an UDP based protocol that needs packet encryption) I increment the counter and use it as IV. However, since I will generally need that protocol to transfer files and to send for very very extended periods of time, in principle for very large files it is conceivable to send more than $2^{32}$ packets, or over the years it is conceivable to send out $2^{32}$ keepalives. To keep the IVs always unique, I would probably need to use a 64 bits integer, but that is 4 bytes more of overhead per packet, that can sum up to quite large quantities which I would like to avoid if not strictly necessary. So I wonder: how bad it is to reuse the IVs with AES/GCM? Can I have an idea of how dangerous that can be? I mean: if as soon as I repeat an IV once I get immediately so easily exposed to an attack that I could just give out my key publicly, then I have to take countermeasures. However, if that becomes dangerous only when I use the same IV a lot of times, that is completely another thing.
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I've just cloned a full functioning website with its database. But on localhost: The index page shows a white page When I go to the login page, it shows a login form with basic HTML, without CSS styles, and no template. When I try to log in, it redirects me to , which I am not allowed to access. I've tried to compare another page just now and it isn't white, but it doesn't show what it needs to show too. It shows the following code. [t001_01_main.tpl.php] var addthis_config = addthis_config||{}; addthis_config.ui_email_note = 'verbind: test setting E-mail text'; */?> I'm running the localhost on a Macbook Pro without MAMP. Other Drupal installations work fine. I have tried putting the following code, but it gives the same result. error_reporting(-1); // Have PHP complain about absolutely everything $conf['error_level'] = 2; // Show all messages on your screen, 2 = ERROR_REPORTING_DISPLAY_ALL. ini_set('display_errors', TRUE); // These lines just give you content on WSOD pages. ini_set('display_startup_errors', TRUE); I've looked into WPOD, but I can't access anything on the site. In /etc/apache2 there isn't any error.log file. The problem isn't with one page; the user page is plain HTML and when logging in my site keeps redirecting to https:// (like said in the second paragraph). So many solutions found about WPOD can't be tried because I can't login. The Drupal version of this project is 7.36, php version of my localhost is 5.6.19 I've tried updating the drupal version to 7.51 I've tried using php 5.4 (oldest version I have installed) There are no new errors in the watchdog table Live site works like a charm , other local websites that I've imported to localhost allso work
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How can I see the error messages when the site I am working on gets a white screen?
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I installed Ubuntu but Windows is still there. My old Ubuntu CD won't work on the ASUS Desktop as there's no CD drive. How do I completely remove Windows?
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Hello can someone give me short tutorial how to: Remove Windows 7 from my dual boot system (Ubuntu/Windows7) Let me use free space as new partition for data (so I don't need to extend Ubuntu itself here) Remove windows 7 option from boot screen Update: Thanks to Lekensteyn answer I successfully deleted windows. Now I created new partition (formatted to ext4), but I can not use it. I cannot copy files there, only as root. Also when booting, Ubuntu complains it didn't find /windows partition (of course it didn't, I removed it). I feel like I should update some tables or what, any ideas?
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A) No, I didn't miss you. B) Yes, I didn't miss you. C) No, I did miss you. D) Yes, I did miss you. According to my common sense perfect answers can be C) and B) only, and reason behind it is- "didn't" is used/asked in the question, so if the person answering the question agrees with the person asking the question he will probably say "Yes, I didn't miss you," and if he does not agree he should answer "No, I did miss you." I have checked online everywhere and all four are treated as correct. So, just asking to the experts present here for their views on this, in any context of English language or usage. EDIT1 : Actually i was hoping that the SPEAKER Of QUESTION can tweak the question to get the desired answers only( only (B), and (C) in my case).But, the English seems to be weak to me after reading all the answers and responses from the experts,as the SPEAKER OF ANSWER totally has the control of the responses and he can speak any of the all four answers A,B,C,D. What if the question asked was : Do you miss me a little? OR Did you miss me a little? OR SIMPLY Did you miss me? I guess again all the previous answers A,B,C,D are correct. ;-)
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The Germans have doch and the French have si as a word that means "yes" in response to a negative question, such as: Don't you want some ice-cream? Yes [I do]! In English, we only have yes (as far as I know) and further clarification is required in order to be unambiguous. Did we ever have such a word in English and, if so, what happened to it? If not, given the French and Germanic influences on English, any idea why not?
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I recently listened to a podcast in which the narrator described an unresolved obstacle as a "problem that needed solved." My initial assumption was that he had meant to say "problem that needed to be solved," but had misspoken. However, he used the same phrase again later. I had never encountered this phrase before, so I did a google search for the exact phrase and found a surprisingly diverse set of results including user comments, professional web content, and books. I am now curious. Is this, seemingly grammatically incorrect, phrase commonly used in certain regions or is there some other known origin?
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In the (and possibly elsewhere), the following construction is possible: This car needs washed. (=needs to be washed) The room needs cleaned. (=needs to be cleaned) It appears that, if a verb like needs is followed by a passive construction in the infinitive, the "to be" portion is left out. This construction sounds so unnatural to my ear that I have no intuition as to the extent to which it can be extended to other words and contexts. If anyone here is a native speaker of this dialect of English, perhaps they can help to explain the limits on its use. My basic question is: how productive is this particular construction among those who use it? To be more specific, can this construction be used with any verb (if that verb can be immediately followed by a passive construction, of course)? That is, would (any of) the following be acceptable, for example? At this restaurant, we always wait seated. (=wait to be seated) My kid hates picked last in sports. (=hates to be picked) We all want loved. (=want to be loved) If this construction is restricted, then which verbs can be used, aside from need? Edit: What I am really hoping for here is that there is someone who happens across this question that can say, "I actively use this construction, and here's what I can and can't say."
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It's when you know you're gonna do something that you shouldn't but you do it anyways, like dropping something even though you had no intention of dropping it but the thought of dropping it crossed your mind and you consciously decided not to drop the thing but you did anyways. The thought process is pretty much "I know I shouldn't do this but I'm going to even though I don't want to". Might be a medical term, maybe there isn't even a word for it. Best use I can think of is: "The patient has been suffering from ____ for a long time" I'm seeking the word or definition for the act of doing said thing even though you don't want to and made a conscious decision not to but still do. It's not a compulsion, but more of a momentary dissonance(?) between your brain and your body about what to do. Not sure if this will clarify it enough.
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I am reading Of Mice and Men, and I am trying to come up with a word that describes how George manages to shoot Lennie at the end of the book. I have come up with Self Discipline, and Overcoming Weakness, but none of those really seem to suffice. Any suggestions would be great!
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When I clicked on the Questions button, it showed a new tab named interesting with a list of questions. But I then couldn't locate it again. Is it possible to get the list of interesting questions?
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One day I directed to SO and was met with the awesome Interesting page, which I really like. But when I travel away from it, I have to re-enter the query string to get it back. Is there a plan to make this tab visible so I can click to it anytime?
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I'm always trying edit to make my questions better, but it seems it's not working so well. Could you give me some advice on how I can improve my questions? ... Well, I'm banned again, help... I've delete some of my poor questions.
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If you are reading this, you may have been affected by one of our post quality bans. If so, it is important that you to understand what has happened and how to regain the permissions that you lost. While trying to ask a question, one could see: We are no longer accepting questions from this account. See to learn more. Likewise, for answers: We are no longer accepting answers from this account. See to learn more. Why am I getting this message? Are deleted posts taken into account too? Is a question/answer ban the same as a suspension? How do I avoid getting a question ban? How long do I have to wait before I can post again? What can I do to release the ban? How can I reactivate my account? Can I simply create a new account? I'll just ask somewhere else on the SE network, and they'll migrate my question to the correct site! Will a ban on one Stack Exchange site affect my standing on other sites in the network? Does this apply to meta sites too? My account is in good standing. Why am I still blocked?
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Let us assume I have some equation like \documentclass{article} \usepackage{cmbright} \usepackage{amsmath} \usepackage{bm} % boldmath % ******** \begin{document} bold not working: \begin{equation} X_\mathbf{n} \end{equation} Let us try bold here: \begin{equation} p_{\bm{n}} \end{equation} \end{document} The problem with that command is, that it changes the font from sans to serif. Strange, isnt it? It leads also to a lot of confusion. Any ideas?
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I would like to use bold symbols in superscript equations. To do so, I use \displaystyle as in \documentclass{standalone} \usepackage{amsmath} \begin{document} $e^{\mathbf{A}t}=e^{\displaystyle \mathbf{A}t}=e^{{\displaystyle \mathbf{A}}t}$ \end{document} The corresponding output is: The first exponential is exactly what I'm looking for. Now, if I add the cmbright package, the corresponding code \documentclass{standalone} \usepackage{amsmath} \usepackage{cmbright} \begin{document} $e^{\mathbf{A}t}=e^{\displaystyle \mathbf{A}t}=e^{{\displaystyle \mathbf{A}}t}$ \end{document} yields: As one can see, in the left exponential the A symbol is not bold, and the other symbols are larger (as expected with \displaystyle). I guess there is a pretty simple explanation about cmbright but I am not aware of it. Any clues to get the bold symbol AND the normal size with cmbright?
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Phase velocity is defined as $v_p=\frac{\omega}{k}$ and is described in various textbooks as being the speed at which the phase of a wave propagates. If you have a wave train that is modulated by an envelope, then while the group velocity gives you the speed of the envelope the phase velocity gives you the speed of the wave within the envelope. Do $v_p$ and $v_g$ have any meaning if we are only considering one sinusoidal wave and not a superposition of such waves? I have been told that the speed of a single sinusoidal wave is its phase velocity, and that phase velocity is what we're really referring to when we talk about a wave's speed. However, how can phase velocity be greater than light if this is the case? The standard response seems to be that the group velocity is what determines the rate of information transfer, and it is this velocity that cannot exceed $c$. However, in special relativity a simple limit is set on the speed of any particle, and photons must travel only at speed $c$. If $v_p>c$ then does this not mean that the physical wave within the envelope is superluminal, and so the photons that comprise it are also superluminal?
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I understand that information cannot be transmitted at a velocity greater than speed of light. I think of this in terms of the radio broadcast: the station sends out carrier frequencies $\omega_c$ but the actual content is carried in the modulated wave, the sidebands $\omega_c\pm\omega_m$. The modulation envelop has its group velocity and this is the speed at which information is being transmitted. We also know, for example, that x-rays in glass have a phase velocity which is greater than the speed of light in vacuum. My question is, what exactly is it that is travelling faster than the speed of light? EDIT: I know it couldn't be anything physical as its superluminal. My problem is, what is it that has absolutely no information content yet we associate a velocity with it.
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computer: MacBook Pro (13-inch, Mid 2012) - 1TB SSD - Intel HD Graphics 4000 1536 MB - 8 GB 1600 MHz DDR3 - 2.9 GHz Dual-Core Intel Core i7 Currently, have one monitor setup using a thunderbolt to HDMI adapter all good there, but how can I add another external monitor? The second monitor has a VGA, DisplayPort, HDMI, and USB 2 port. Both monitors are HP. What's the cheapest way to run two external monitors in this situation? I would prefer an HDMI cable method since I already have two of these. I will not have my MacBook open when using two monitors. Thank you in advance for your time and help!
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How do I find out the number, type, resolution & refresh rate of additional monitors I can attach to my MacBook or MacBook Pro? This is an attempt at a canonical QA, as per the Meta QA - to try prevent the myriad "same but different" questions we get on every possible combination of computers, cable & monitors There are perfectly good resources out there that Ask Different should not have to duplicate the efforts of.
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Salam/Hi, I have two winform, 1 named as "fudafrm" another is "loginfrm".I want to control tabs or close 3,5 and 8 tab which is located in fudafrm through loginfrm,when Id and password is correct. fudafrm is this: AND loginfrm is : I tried thees code in loginfrm: (wrong codes) if (txt_userid.Text == "user" && txt_password.Text == "user") { Form f1 = new fudafrm(); TabControl.TabPageCollection("tabpage3").hide(); TabControl.TabPageCollection("tabpage5").hide(); TabControl.TabPageCollection("tabpage8").hide(); this.Hide(); } else { MessageBox.Show("Invalid User Name & password","Error"); } kindly help me for controlling tabs through other forms. I am using windows form C# visual studio 2010.
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How to hide TabPage from TabControl in WinForms 2.0?
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Theorem: Let $V$ be a linear space and $V_{0}$ is its subspace. Also let $p$ be a finite convex functional in $V$ and $l_{0}$ is linear functional in $V_{0}$. While $l_{0}(v)\le p(v),v\in V_{0}$ Then exists linear functional $l$ defined in $V$, which is extension of functional $l_{0}$ and $l(v)\le p(v),v\in V$ Stein's proof in functional analysis page$_{21}$ : ...... Well-order all vectors in $V$ that do not belongs to $V_0$ , and denote this ordering by $\lt$ . Among these vectors we call a vector $v$ "extendable"if the linear functional $l_0$ has an extension of the kind desired to the subspace spanned by $V_0 , v$ and all vectors $\lt v$ . What we want to prove is in effect that all vectors not in $V_0$ are extendable . ...... Since we can not apply well-ordering principle to find the largest element in $V$ . If we have proved all vectors not in $V_0$ is extendable , then how to show $V$ is extendable ?
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In the 4th book of Stein and Shakarchi, the statement of the Hahn-Banach theorem is as follows: Suppose $V_0$ is a linear subspace of $V$ and $p$ is a real sub-linear function on $V$, and that we are given a linear functional $l_0$ on $V_0$ that satisfies $$l_0(v)\leq p(v) ~\forall ~v\in V_0$$ Then $l_0$ can be extended to a linear functional $l$ on $V$ that satisfies $$l(v) \leq p(v)~ \forall ~ v \in V$$ The proof given is as follows: We have already proved that if $l_0$ can be extended to a subspace W, then it can also be extended to the subspace $W+ w$ for any vector $w$. We well order all the vectors in $V$ that do not belong to $V_0$, and denote this ordering by $<$. Among these vectors, we call a vector $v$ extendable if the linear functional $l_0$ has an extension of the kind desired to the subspace spanned by $V_0.v$ and all the vectors $<v$. What we want to prove is in effect that all vectors not in $V_0$ are extendable. Assume the contrary, then because of the well-ordering we can find the smallest $v_1$ that is not extendable. Now if $V_0'$ is the space spanned by $V_0$ and all the vectors $<v_1$,then by assumption $l_0$ extends to $V_0'$. The previous step, with $V_0'$ in place of $V_0$ allows us then to extend $l_0$ to the subspace spanned by $V_0'$ and $v_1$, reaching a contradiction. This proves the theorem. Firstly, how does proving that all vectors not in $V_0$ are extendable imply that an extension exists for the whole space? We know that for any $v \notin V_0$ there exists a valid extension, say $l_v$ for the space spanned by $V_0,v$ and all vectors $<v$. Say we define $l(v):=l_v(v)$. Now we take an arbitrary $w>v$. Couldn't it happen that $l_w(v) \ne l_v(v)$. In this case how can one define $l$? Will it help if we change the definition of "extendable" to something like: A vector $v \notin V_0$ is called extendable if $l_0$ has an extension of the kind desired to the relevant subspace which is equal to the already defined functionals $l_w~ \forall w<v$ in the relevant subspaces? Also, how does one get the statement :"Now if $V_0'$ is the space spanned by $V_0$ and all the vectors $<v_1$,then by assumption $l_0$ extends to $V_0'$."
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In the example from the title, is it mandatory to use that? The original sentence I picked up was from a checkbox marked Confirm you are not a spammer which I thought should be Confirm that you are not a spammer though I have seen a lot of usage without that after searching around.
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Consider the following use case: Please check the username and password are correct. Please check that the username and password are correct. In this case, I would say that that is required because it feels more natural to me and so the flow is better. However, is the lack of that wrong in this case? The question boils down to: when is that optional? See . A quick summary: That is optional if the pronoun is the object. That is required if the pronoun is the subject. I think that we fall into the second case: that is required because the relative pronoun is the subject. But I'm not sure if I'm interpreting these rules correctly. Can someone please advise?
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I could not find a dedicated photo-editing section, hence posting here. Apologies if wrong place. Query: I have thousands of photos, which I need to show time/date/custom-text on all photos. Editing all individuals photos will be impossible! Is there any way to do this in batch-mode?
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Is there any utility which will read a photo's date and time from its EXIF data and embed it into the corner of the photo?
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I'm sure variations on this come up a lot, but I was specifically interested in a response to a claim made by a particular article: The article is aiming to disprove the idea that an 'observer' collapsing a wave function has anything to do with consciousness or human observers. At one point it argues that the reason an electron in the double slit experiment has its wave function collapsed when detected before entering one slit or the other is due to the photons fired at it to detect its position having momentum and physically interacting with it. The author uses the analogy of tennis balls being fired into a dark room and using a tennis racquet to detect them - the method of detection causes a change in their behaviour. Now in this instance that's all well and good, but firing photons is not the only means of detecting something. In the Schrödinger's cat thought experiment, for instance, a Geiger counter is used. As far as I understand it, these simply detect passively rather than firing out photons with momentum. I know many people disagree with the wave function collapse theory and prefer decoherence (which I'm still wrapping my head around) but I'm interested to know if this is something that's explained within collapse theory or if it's something that's seen as disproving it.
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I'm working off the article, . I think it's well-written, but I'm not convinced about this part: So what is causing the change in the particle’s behaviour? In the example given above, when electrons are fired at a fluorescent screen, when we bombard the electrons with photons the interaction changes the state of the system catastrophically as, despite lacking mass, photons do carry momentum. Here the author strongly implicates the momentum of photons as being responsible for the collapse. But is that correct to say? I have read that the verified that obscuring which-way information restores wave-like behavior. So it feels to me it's more about some "outer" state (perhaps well-characterized as "information") that we don't yet understand that collapses the system, not per se the photon-electron interaction. Or am I wrong, and in fact for example, the process of obscuring in the quantum eraser experiments somehow "undoes" the photon-electron interaction or restores the quantum state through another interaction?
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I would like to know how I can loop through pages with a specific template name. I have several pages where the admin can select a template name of SALE. I want to display all content with this template name via the loop. Any ideas are much appreciated!
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I want to know if it's possible to get the ID of a page with a specific template. Is this possible to get the ID of a page that assigned to "page-special.php"?
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Need help guys about this form, saving data to database is good my problem is I can't save files in database don't know what to change do I need to add var file or add <form id=''> really don't know what todo and I don't have any idea on how to save files using ajax form and I'm not really good in jQuery/ajax. please help. <textarea class='message' cols ='30' rows ='5' id = 'message'></textarea> <form method="post" enctype="multipart/form-data"> <label for="fileToUpload"><img src="img icon.png" title="Attach Image"> </label> <input id="fileToUpload" name="fileToUpload" type="file" onchange="document.getElementById('file').value = this.value.split('\\').pop().split('/').pop()"/> <input type="text" name="file" id="file" class="file"> <button class="submit" id="submit" name="submit" >Comment</button> </form> <script> $('.submit').click(function(){ var name = '<?php echo $row['name'];?>'; var message = $('.message').val(); if(message.length>1){ $.ajax({ url:'upload.php?id=<?php echo $id;?>', data:'name='+name+'&message='+message, type:'post', success:function() { $('.message').val(''); listComments(); alert('Post Message'); } }) }else{ alert('PLEASE DO RIGHT A MESSAGE BEFORE SENDING'); } }) </script> upload.php <?php $id = $_GET['id']; $name = $_SESSION['u_uname']; $file = $_FILES['fileToUpload']['name']; $target_dir = "uploads/"; $target_file = $target_dir . basename($_FILES["fileToUpload"]["name"]); $message = mysqli_real_escape_string($conn,$_POST['message']); $daterep = date('Y-m-d H:i:s'); $qry = "INSERT INTO forum_answer (topicid,name,message,daterep,file) VALUES ('$id','$name','$message','$daterep','$target_file')"; $log = mysqli_query($conn,$qry); move_uploaded_file($_FILES['fileToUpload']['tmp_name'],$target_dir.$file); ?>
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I would like to upload a file asynchronously with jQuery. $(document).ready(function () { $("#uploadbutton").click(function () { var filename = $("#file").val(); $.ajax({ type: "POST", url: "addFile.do", enctype: 'multipart/form-data', data: { file: filename }, success: function () { alert("Data Uploaded: "); } }); }); }); <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/2.2.0/jquery.min.js"></script> <span>File</span> <input type="file" id="file" name="file" size="10"/> <input id="uploadbutton" type="button" value="Upload"/> Instead of the file being uploaded, I am only getting the filename. What can I do to fix this problem?
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I'm facing with the Fatal error: Maximum execution time of 30 seconds exceeded. I'm trying to catch this error and show the error message to user but it seems that "try...catch..." in PHP can't handle this. I have tried to use "register_shutdown_function" but not success, the script continue to run and display blank page. $max_execution_time = ini_get("max_execution_time"); ini_set('display_errors', false); ini_set("max_execution_time", $max_execution_time * 0.8); register_shutdown_function([$this, 'shutdownHandler']); ... function shutdownHandler() { $error = error_get_last(); if (($error['type'] === E_ERROR) || ($error['type'] === E_USER_ERROR)) { ... } } Would anyone help me in this case?
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I can use set_error_handler() to catch most PHP errors, but it doesn't work for fatal (E_ERROR) errors, such as calling a function that doesn't exist. Is there another way to catch these errors? I am trying to call mail() for all errors and am running PHP 5.2.3.
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I have a program in Java (with a swing gui), and I would like only 1 instance ever to exist. If it attempted to open another instance of the program I would like the current instance to be brought to the foreground. How do I do this? Thanks in advance.
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Sometime I see many application such as msn, windows media player etc that are single instance applications (when user executes while application is running a new application instance will not created). In C#, I use Mutex class for this but I don't know how to do this in Java.
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Is it a subject? Also, what sort of sentence is this?
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I read the following definition for , but the many syntactical terms (based on Latin) confound me: accusative and nominative absolute. a construction in English, especially colloquial English, consisting of a pronoun in the accusative case joined with a predicate that does not include a finite verb and otherwise identical with the nominative absolute (as him being my friend in “him being my friend, I granted his request”) I first heard this at 54:31 in .
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Though I'm also interested in general slang words, I'm more specifically asking for slang used in D&D 3.5e. While looking at the comments of a question, I saw someone introducing BAB as abbreviation for Base Attack Bonus to the person asking the question. Though I'm familiar with some of the most common jargon, like the standard STR CON DEX INT WIS CHA, I would like to know what other jargon terms are used. Is there a list somewhere with common and somewhat uncommon jargon in (tabletop) RPGs, specifically for D&D?
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Words like 'campaign', 'system', 'dX', etc. Is there a good web resource with them all on a single page?
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A few days ago my screen turned completly white and I was not able to do anything. I had to kill my PC with the power-button and restart it. Everything worked fine so I thought is was just some kind of system-crash. But 5 minutes ago it happened again. I killed my PC again but it would not start for a few minutes. Only the fans started turning, but I could not even hear the high pitched sound (which I think comes from the BIOS booting). Now suddenly my PC was able to boot again and showed me this message in black on White while booting: "The Anti-Virus Software you have installed on your computer is now cleaning up.. Successfully done" (translated by me). I googled a bit and found out there is ransomware going round that does exactly that. So may I be infested? Even this message that my anti-virus program is cleaning up sounded pretty suspicious..
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What should I do if my Windows computer seems to be infected with a virus or malware? What are the symptoms of an infection? What should I do after noticing an infection? What can I do to get rid of it? how to prevent from infection by malware? This question comes up frequently, and the suggested solutions are usually the same. This community wiki is an attempt to serve as the definitive, most comprehensive answer possible. Feel free to add your contributions via edits.
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Recent news reported about the discovery of a "Prime Conspiracy" which can be read about . In summary, researchers have discovered that the last digit of prime numbers have a greater predictability than random. The cited example is that primes ending in 9, have a 65% chance of the next prime ending in 1. I am curious if any thought has been generated around the impact this might have to cryptography, namely popular encryption methods like RSA?
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reports: Two mathematicians have uncovered a simple, previously unnoticed property of prime numbers [...]. Prime numbers, it seems, have decided preferences about the final digits of the primes that immediately follow them. Among the first billion prime numbers, for instance, a prime ending in 9 is almost 65 percent more likely to be followed by a prime ending in 1 than another prime ending in 9. Do these insights make breaking keys based on primes more mathematically plausible in a shorter amount of time?
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A sequence $\{x_n\}$ is given by $x_n= a_n-\sqrt{2n}$ and $a_n$ is given by $a_1=1$ and $a_n=a_{n-1}+\frac{1}{a_{n-1}}$. Please help. I could not find a way out.
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Today, we had a math class, where we had to show, that $a_{100} > 14$ for $$a_0 = 1;\qquad a_{n+1} = a_n + a_n^{-1}$$ Apart from this task, I asked myself: Is there a closed form for this sequence? Since I didn't find an answer by myself, can somebody tell me, whether such a closed form exists, and if yes what it is?
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