How to get OSM API key in QGIS?
Add an API key to QGIS for QOSM layer
Is it possible to get back your deleted Terraria character? Can Blender render pngs with the background transparent? Classify all groups with order $pq$, $p$ is not equal to $q$ I am reading the following material:  . At page 5, there is a proof classifying all groups with order $pq$(they are all primes and $p$ is not equal to $q$). I am lost in the last two sentence, which claims the semidirect product are all isomorphic. Could someone help me to understand it? Thanks! How can I require an optional Perl module if installed? I have Perl code which relies on Term::ReadKey to get the terminal width. My installation is missing this module, so I want to provide a default if the module isn't present rather than throw an exception. How can I conditionally use an optional module, without knowing ahead of time whether it is available. # but only if the module is installed and exists use Term::ReadKey; ...  How can I accomplish this? How do I know if an ability is magical? Often confusion arises when the  spell is used, an  is worn, or the 's anti-magic ray is employed, whether a given character's ability will still function.   The spell does give you some guidelines on how to adjudicate the effects of the loss of magic but says very little about how to determine what is affected.  In short, how do I tell if an ability is magical? Java string to date conversion Transforming Differential Equation to a Kummer's Equation I'm trying to transform an equation of the form $$ yw^{\prime\prime}(y) - [b - ay] w^\prime(y) - [d + ey]w(y) = 0 $$ into the form of a Kummer's or confluent hypergeometric differential equation: $$ y w^{\prime\prime}(y) + [f - y] w^\prime(y) + g w(y)  = 0 $$ I know it may have something to do with merging two of the singularities of the original equation, and maybe doing something with $y$, making it $\frac{y}{b}$ and taking b to infinity, but I don't know and can't find the details for this process, and for my equation specifically. There's not too much difference between the two but just enough so that I can't get it. Thanks in advance for any help! I'm trying to print types like off_t and size_t.  What is the correct placeholder for printf() that is portable?  Or is there a completely different way to print those variables? Arc length parameterization lying on a sphere Validate inputs that are not inside a form with jQuery Validation plugin How can I validate some inputs that are not inside a form tag?  All the samples I found have a form tag, but I want to validate some inputs that are not inside a form. Expected Value of the maximum of two exponentially distributed random variables I want to find the expected value of $\text{max}\{X,Y\}$ where $X$ ist $\text{exp}(\lambda)$-distributed and $Y$ ist $\text{exp}(\eta)$-distributed. X and Y are independent. I figured out how to do this for the minimum of $n$ variables, but i struggle with doing it for 2 with the maximum.  (The context in which this was given is waiting for the later of two trains, with their arrival times being exp-distributed).  Thanks! How much effect does the Bernoulli effect have on lift? I understand that the Bernoulli effect is a flawed explanation for the cause of lift, and does not cause much at all, but how much?   Is there any experimental data on the force caused by the Bernoulli effect? Maybe implicitly through data of the pressure difference between the top and underside of an aeroplane's wings. After that, I assume I could (crudely approximating the pressure to be acting perpendicularly to the flight direction) use $\Delta P A$ to work out the net force on the plane.    Perhaps there is another way to quantitatively analyse the extent to which the Bernoulli effect causes lift.  Edit: see  short cartoon (content similar to Mike Dunlavey's answer). Can I convert a C# string value to an escaped string literal? In C#, can I convert a string value to a string literal, the way I would see it in code? I would like to replace tabs, newlines, etc. with their escape sequences. If this code: Console.WriteLine(someString);  produces: Hello World!  I want this code: Console.WriteLine(ToLiteral(someString));  to produce: \tHello\r\n\tWorld!\r\n Putting altered social media logo icons on my website, can I get sued? I would say most websites with a somewhat thought-through graphical design use social media icons (i.e Twitter, Facebook, YouTube, etc) which are altered to fit the theme and design of the site.  Now, my boss insist we only use the ones provided by say Facebook or Twitter themselves (in fear of getting sued or lose credibility), but sometimes it just doesn't look very good on the site.   What is the common practice for these things? What do you risk by using an altered logo? What should I tell my boss?  I'll provide a few examples, what'd happen if I put any of these on a site? Yesterday I upgraded my Ubuntu 18.10 to Ubuntu 19.04, and after the restart, the trash icon and my Desktop files have disappeared from the UI. If I go to the Desktop folder from my personal folder, I can see the files, but my Desktop is empty.  How can I show my files in the Desktop again? Imagine a standard machine-learning scenario:     You are confronted with a large multivariate dataset and you have a   pretty blurry understanding of it. What you need to do is to make   predictions about some variable based on what you have. As usual, you   clean the data, look at descriptive statistics, run some models,   cross-validate them etc., but after several attempts, going back and   forth and trying multiple models nothing seems to work and your   results are miserable. You can spend hours, days, or weeks on such a   problem...   The question is: when to stop? How do you know that your data actually is hopeless and all the fancy models wouldn't do you any more good than predicting the average outcome for all cases or some other trivial solution?  Of course, this is a forecastability issue, but as far as I know, it is hard to assess forecastability for multivariate data before trying something on it. Or am I wrong?   Disclaimer: this question was inspired by this one  that did not attract much attention. It would be nice to have detailed answer to such question for reference. Notes:  Answers will occasionally be moved to the  when there are too many of them. When using them to report bugs, keep an eye on the post.    This site, Meta Stack Exchange, is usually used as a &quot;test bed&quot; for pending changes happening to the way text is rendered on all network sites. Changes to text rendering that are going to be rolled out to the network are usually deployed here first to test them out and fix any potential glitches. Currently, there are no such changes pending, but if there were, keep in mind that text posted here may render differently from the other sites until the changes roll out to them as well.    As per Jeff's suggestion in : You can use this question as a formatting sandbox. You can:  edit  itself ( questions such as this one require only 100 reputation to edit instead of 2,000) post answers to this question (This question might be , requiring earning 10 reputation on this site to answer) post comments to this question or its answers test suspected bugs with the editor or the rendering post ponies (only when mods are asleep)   Beware that since the  in December 2010, and  added in March 2011, no syntax highlighting is applied unless the question's tags or an inline hint enable it. So, to test highlighting here in the sandbox:  , you can use GitHub-flavor fenced code blocks in your posts, specifying the language after the opening fence: ```html While not hinted otherwise: &lt;html&gt;&lt;/html&gt; source &lt;b&gt;goes&lt;/b&gt; &quot;here&quot;. ```  ```js var a = 3; while (not (a &gt; 0)) {     alert(&quot;JavaScript code &lt;b&gt;goes&lt;/b&gt; here.&quot;); } ```   Or:  Create code blocks in any way (using the fence notation above, the four-space indent form, or using HTML &lt;pre&gt;&lt;code&gt; tags).  Save your post.  Use your browser's developer tools to edit the resulting HTML. To open developer tools, press F12, or ⌥⌘ I on Mac.  Find the &lt;pre&gt; element and add the attribute class=&quot;prettyprint&quot;, or change it into one of the valid syntax hints linked above, like class=&quot;lang-vb prettyprint&quot;.  Run the following in the location bar: javascript:prettyPrint(); or prettyPrint() in the console.     Answers that are considered annoying or obnoxious, or that cause breakage for users, will be deleted. This is . How to get speech output from entered text by using command-line?  Also facility to change speech rate, pitch, volume etc using simple command. If $A$ is a non-empty set, then $A \notin A$ Exercise 3.2.2 Use the axiom of regularity and the singleton set axiom to show that if $A$ is a set then $A \notin A$.  Axiom of Regularity: If $A$ is a non-empty set, then there is at least one element x of A which is either not a set, or is disjoint from A.  Singleton Set Axiom: If $a$ is an object, then there exists a set $\{a\}$ whose only element is $a$, we refer to $\{a\}$ as the singleton set whose element is $a$ Furthermore, if $a$ and $b$ are objects, then there exists a set $\{a,b\}$ whose only elements are $a$ and $b$    I think I can give the proof when A is the non-empty set which contains finite elements. However, can anyone give any hint for the general case?  Suppose $A \in A$   Then eixsts $x$ such that either $x$ is not a set or $x \cap A$=$\emptyset$  Then it is clear thar $x \ne A$ (if $x = A$, then $x \cap A \ne \emptyset$)  We observe that as an element, $A$ $\ne$ $x$, $A$ $\in$ $A$  Then $A$ $\in$ $A-x$   Define the new set $A-x$ as $A_1$  then exists $x_1$ such that $A \in A_1-x_1$  After finite steps  we find that $A \in \emptyset $  which leads to contradiction. Adverb sentence query He is arguably the best actor of his generation   In the above sentence the adverb is placed just after "be" Can we use adverb after "be"? If we can use then please explain properly because I have studied that adverb can be used before adjective and adverb .