Cannot start Eclipse from Unity Launcher
How to pin Eclipse to the Unity launcher?
Is there any rule for when it is better to use genitive case or noun as adjective? I'm not sure if there is any difference in meaning in this example:     The department of accounting       The accounting department   Can I also use both forms in situations like:     The restaurants of Paris / The Paris restaurants      The room window / The window of the room Moderators accepting answers on user's behalf after a certain time period Is drawing multiple cards an atomic action? Is drawing multiple cards an atomic action, or do effects triggered by drawing a card trigger for each card drawn instead?  Consider , which reads:     Whenever a player draws a card, Spiteful Visions deals 1 damage to that player.   If a player were to be compelled to draw more than one card, would that player be dealt the damage all at once, or one at a time? For example, how many times would  need to be activated to prevent all damage?  Furthermore, if there exist additional effects that are triggered by damage dealt in this way, are such effects resolved together atomically or is each resultant effect resolved individually?    How about tutors, or other cards not using the word 'draw', eg:      If you would draw a card, look at the top three cards of your library instead. Put one of those cards into your hand and the rest on the bottom of your library in any order. I've read in several places that one motivation for category theory was to be able to give precise meaning to statements like, "finite dimensional vector spaces are canonically isomorphic to their double duals; they are isomorphic to their duals as well, but not canonically."  I've finally sat down to work through this, and -  Okay, yes, it is easy to see that the "canonical isomorphism" from $V$ to $V^{**}$ is a functor that has a natural isomorphism (in the sense of category theory) to the identity functor.  Also, I see that there is no way that the functor $V\mapsto V^*$ could have a natural isomorphism to the identity functor, because it is contravariant whereas the identity functor is covariant. My question amounts to:     Is contravariance the whole problem?   To elaborate:   I was initially disappointed by the realization that the definition of natural isomorphism doesn't apply to a pair of functors one of which is covariant and the other contravariant, because I was hoping that the lack of a canonical isomorphism $V\rightarrow V^*$ would feel more like a theorem as opposed to an artifact of the inapplicability of a definition.  Then I tried to create a definition of a natural transformation from a covariant functor $F:\mathscr{A}\rightarrow\mathscr{B}$ to a contravariant functor $G:\mathscr{A}\rightarrow\mathscr{B}$. It seems to me that this definition should be that all objects $A\in\mathscr{A}$ get a morphism $m_A:F(A)\rightarrow G(A)$ such that for all morphisms $f:A\rightarrow A'$ of $\mathscr{A}$, the following diagram (in $\mathscr{B}$) commutes:  $$\require{AMScd}\begin{CD} F(A) @&gt;m_A&gt;&gt; G(A)\\ @VF(f)VV @AAG(f)A\\ F(A') @&gt;&gt;m_{A'}&gt; G(A') \end{CD}$$  This is much more stringent a demand on the $m_A$ than the typical definition of a natural transformation.  Indeed, it is asking that $m_A=G(f)\circ m_{A'}\circ F(f)$, regardless of how $f$ or $A'$ may vary. Taking $\mathscr{A}=\mathscr{B}=\text{f.d.Vec}_k$, $F$ the identity functor and $G$ the dualizing functor, it is clear that this definition can never be satisfied unless $m_V$ is the zero map for all $V\in\text{f.d.Vec}_k$ (because take $f$ to be the zero map). In particular, it cannot be satisfied if $m_V$ is required to be an isomorphism.     Is this the right way to understand (categorically) why there is no natural isomorphism $V\rightarrow V^*$?   As an aside, are there any interesting cases of some kind of analog (the above definition or another) of natural transformations from covariant to contravariant functors?  Note: I have read a number of math.SE answers regarding why $V^*$ is not naturally isomorphic to $V$. None that I have found are addressed to what I'm asking here, which is about how categories make the question and answer precise. ( was closest.) Hence my question here. How do remove the CD / DVD install as a source for apt-get packages when installing new features? I'm running a Ubuntu server (9.0.4 'Jaunty') as a VMware image.  It's a real pain on the odd occasion I need to install a new package to have to fish out the install CD-ROM, and make it available to the VMware image so I can continue the package install.  Is there any way to take the original installation media out of the list of source packages - I'm assuming all packages will be available on the internet.  Thanks. Weird sharp vertices with subdivision modifier I have a simple skull model, to which I applied the subdivision modifier. For the most part everything works as expected, except I keep getting these weird sharp vertices and I can't seem to figure out how to flatten them.    I'm using Blender 2.8. Is this some kind of feature I can disable/enable for particular vertices? The distance between the sharp vertices and the gray outline differ.    Any suggestions please? Thank you!  EDIT: I also tried selecting as both - vertexes and edges and then applied Edge->Clear Sharp, but nothing changed. How do I change the command that a launcher item launches? Exact sequence of sheaves with non exact sequence of global sections Let $X$ be some topological space. By $\mathcal{F}_i$ we denote some sheaves of abelian groups on $X$. The sequence of sheaves and morphisms  $$\mathcal{F}_1\longrightarrow \mathcal{F}_2\longrightarrow \mathcal{F}_3\longrightarrow... $$ is said to be exact if for each $x\in X$ the corresponding sequence of stalks $$(\mathcal{F}_1)_x\longrightarrow (\mathcal{F}_2)_x\longrightarrow (\mathcal{F}_3)_x\longrightarrow... $$ is exact. However if the sequence of sheaves is exact than the sequence of global sections is not necessarily exact! (The most famous example is the sequence of sheaves $$0\longrightarrow\mathbb{Z}\hookrightarrow \mathcal{O}\stackrel{\exp}{\longrightarrow} \mathcal{O}^*\longrightarrow0$$ considered as sheaves on $\mathbb{C}-\{0\}$, where $\mathcal{O}$ is a sheaf of holomorphic functions, $\mathcal{O}^*$ is a sheaf of holomorphic functions with no zeros).  So, could you give me some easy examples of such phenomenon ? Is there an elegant way to have performant, natural sorting in a MySQL database?  For example if I have this data set:   Final Fantasy Final Fantasy 4 Final Fantasy 10 Final Fantasy 12 Final Fantasy 12: Chains of Promathia Final Fantasy Adventure Final Fantasy Origins Final Fantasy Tactics   Any other elegant solution than to split up the games' names into their components    Title: "Final Fantasy" Number: "12" Subtitle: "Chains of Promathia"   to make sure that they come out in the right order? (10 after 4, not before 2).  Doing so is a pain in the a** because every now and then there's another game that breaks that mechanism of parsing the game title (e.g. "Warhammer 40,000", "James Bond 007") Prove: If a sequence converges, then every subsequence converges to the same limit. I'm running tests of a variable-size-and-contents test set. Data files are added and removed frequently. I'm looking for an automated way of gathering a file list.  All files are in subdirectories of D; I need the full directory and name added to a text file. However, I only need those files that have a "paired" file, which has the same filename but a different extension (so... different filename, but in a structured way). So, if there is a MyFileName.A and MyFileName.B, then I want D/.../MyFileName added to the file list.  There are .A files without .B files, but no .B files without .A files. If a .A has a .B file, then both files are in the same directory.   Any advice? What is a "year" in Westeros? How to add a class to a given element? I have an element that already has a class: &lt;div class=&quot;someclass&quot;&gt;     &lt;img ... id=&quot;image1&quot; name=&quot;image1&quot; /&gt; &lt;/div&gt;  Now, I want to create a JavaScript function that will add a class to the div (not replace, but add). How can I do that? Compute $\sum_{n=1}^\infty \frac{1}{(n+1)\sqrt[]{n}+n\sqrt[]{n+1}}$ Compute   $\sum_{n=1}^\infty \frac{1}{(n+1)\sqrt[]{n}+n\sqrt[]{n+1}}$ why only square root approach to check number is prime Expanding GCDs Reasoning: $\gcd(a,c) \cdot \gcd(b,c) = \gcd(ab,bc,ac,cc)$ I'm just wondering the reason behind being able to do this:  $$\gcd(a,c) \cdot \gcd(b,c) = \gcd(ab,bc,ac,cc)$$  Is there an elementary proof to the reasoning behind this? I am trying to read a custom (non-standard) CSS property, set in a stylesheet (not the inline style attribute) and get its value. Take this CSS for example:  #someElement {   foo: 'bar'; }   I have managed to get its value with the currentStyle property in IE7:  var element = document.getElementById('someElement'); var val = element.currentStyle.foo;   But currentStyle is MS-specific. So I tried getComputedStyle() in Firefox 3 and Safari 3:  var val = getComputedStyle(element,null).foo;   ...and it returns undefined. Does anyone know a cross-browser way of retreiving a custom CSS property value?  (As you might have noticed, this isn't valid CSS. But it should work as long as the value follows the correct syntax. A better property name would be "-myNameSpace-foo" or something.) What are the rules about using an underscore in a C++ identifier? It's common in C++ to name member variables with some kind of prefix to denote the fact that they're member variables, rather than local variables or parameters. If you've come from an MFC background, you'll probably use m_foo. I've also seen myFoo occasionally.  C# (or possibly just .NET) seems to recommend using just an underscore, as in _foo. Is this allowed by the C++ standard? Is there a systematic way of finding the conjugacy class and/or centralizer of an element? Is there a systematic way of finding the conjugacy class and centralizer of an element? Could the task be simplified if we are working with "special groups" such as $S_n$ or $A_n$? Are there any intuitive approaches? Thanks. Statistics module doesn't show the "Enable access log" checkbox I dont know what to do to show "Enable access log" option.  I activated logging all messages and checked all statistics permissions.  Thanks.