Why do we use a star (*) after a command in LaTeX? I sometimes see some code snippets including star (*) with command such as \hspace*{.5em}, \newcommand*{}, \chapter*{}.  I wonder what the star is for in latex format when collaborating with a command?
Do all starred commands have anything in common? \section* produces an unnumbered section, align* , which is comparable in a way. \newcommand* , which is different.  Stefan Kottwitz :     Commonly, a star symbol * means a version of a command that behaves differently from the original. That often means suppressing numbering but could also refer to special features.   This might answer my question, but perhaps there's more to say (and it's nice to have it as a separate question).  Is there anything all starred commands have in common? Why would one define a starred command as opposed to another, differently named command indicating their semantic difference in the names? It seems that their definitions are usually entirely independent from each other.  Further reading:
$ d_1,d_2\mid n\iff {\rm lcm}(d_1,d_2)\mid n\ $ [LCM Universal Property] examples:         Gift (German) = poison   poisson (French) = fish   embarazada (Spanish) = pregnant   sauce (Spanish) = willow   triviale (Italian) = vulgar   parentes (Portuguese) = relatives   slim (Dutch) = smart Express $\sqrt{3}\sin\theta - \cos\theta$ as: $a\cos (\theta + \alpha) $ Express $\sqrt{3}\sin\theta - \cos\theta$ as: $a\cos (\theta + \alpha) $  Can someone please explain to me how to go about doing this? Is there a DSLR fixed lens camera? When do we double the consonant before '-ing' affix? My son is learning how to spell. He is doing a good job listening to sounds and working out spelling that way (which doesn't work for many words, but at least a lot of common ones), but although he's gotten the -ing chunk, he frequently misses doubling letters in these words.  Is there a guideline for when the end consonant is doubled? He's working on these sorts of words:        riding   sitting   skating   writing   getting Photoelectric effect intensity I understand the PE effect quite well but I'm failing to understand one thing. Intensity is the amount of energy per second incident to a given area.   So can you can increase the intensity by either increasing the electrical energy or making the area smaller? By increasing the electrical energy, what exactly is happening?  I assume that by increasing intensity you are increasing the number of photons incident to an area of the metal thus increasing the rate of photoelectric emission. But why doesn't increasing intensity via more electrical power lead to greater energy of the electrons, if by increasing intensity you are increasing the energy of the incident waves?  I understand the results but I'm trying to understand why the intensity works the way it is thanks Removing phone number from iMessage I'd like to remove my phone number from my iMessage account, but still have my phone enabled to receive messages sent to my email address (also used on iPad, Mac). Is there a way of doing this? What if the answers of a historical locked question become obsolete? New top bar quick reference guide / Where has the link to  gone? Since the new top bar has been rolled out - a number of different people, established and new users alike, have asked questions on where a specific link has disappeared to with the new top bar design. Where has the link to &lt;X&gt; gone? an "X is an X is an X" what does this mean? I am reading  (I must say, with great delight but that's not relevant) and  Canadian is a Canadian is a Canadian A citizen is a citizen is a citizen.  I do not understand this structure. Why not just &quot;A citizen is a citizen&quot;? What is the meaning of repeating this? Some websites have code to "break out" of IFRAME enclosures, meaning that if a page A is loaded as an IFRAME inside an parent page P some Javascript in A redirects the outer window to A.  Typically this Javascript looks something like this:  &lt;script type="text/javascript"&gt;   if (top.location.href != self.location.href)      top.location.href = self.location.href; &lt;/script&gt;   My question is: As the author of the parent page P and not being the author of the inner page A, how can I prevent A from doing this break-out?  P.S. It seems to me like it ought to be a cross-site security violation, but it isn't. Regex for numbers only I haven't used regular expressions at all, so I'm having difficulty troubleshooting. I want the regex to match only when the contained string is all numbers; but with the two examples below it is matching a string that contains all numbers plus an equals sign like "1234=4321". I'm sure there's a way to change this behavior, but as I said, I've never really done much with regular expressions.  string compare = "1234=4321"; Regex regex = new Regex(@"[\d]");  if (regex.IsMatch(compare)) {      //true }  regex = new Regex("[0-9]");  if (regex.IsMatch(compare)) {      //true }   In case it matters, I'm using C# and .NET2.0. I am downloading macOS Sierra from Mac App Store. But I have electricity problem here. Due to which my iMac will lose power after 2 hours. Now I want to pause the downloading so that I can resume the download later on. How can I do that?  Here is a screenshot. What if the answers of a historical locked question become obsolete? My understanding is that a question is historically locked because the information in it is too valuable for the question to be deleted.   But if the "valuable information" becomes obsolete, what happens then?  We cannot modify the question content, or the answers for a historically locked question, right? What is the "last" data that get's backed up, when running pg_dump on a live server? I'm wondering: If I start doing a pg_dump of a very large database (it would take hours), that is still running actively receiving writes, what is then the last data that goes into the backup? Is it:   The data as-it-was, at the point in time where the pg_dump command was initiated. The last changes that it encountered at some point where it was dumping that individual record. Something else.   Bonus question: If I'm trying to dump a database as part of trying to rescue it from corrupt data, will it then make any difference whether I use the directory format or the custom format? AJAX call using admin-ajax URL is returning 400 bad request I have a shapefile with 9000 agriculture fields and what I like to do is to determine for each field (=each polygon) the direction of the longest segment.  For instance, the selected polygon in the screenshot has its longest segment from west to east so I would like to mark give the polygon the attribute W (for west) or either E (for east).   Is there any solution to solve my problem in a fast but generalized way?   I do not need very detailed results. It's just for the interpretation of a question.   I'm seeking an answer using ArcGIS 10.2 for Desktop.  To be more precise on what I'm looking for I try to explain more practical: I'm doing winderosion analysis for a specific area with 9000 fields. As result I have a potential susceptibility for each field. I like to check, if the fields with high susceptibility are correlated to a certain orientation of the fields, e.g. check if most of the fields with high risk are oriented in the main winddirection or not.   The search for the longest segment is not really important for me. It was just an idea I had to determine the direction. So forget about the longest segment if there is a way to determine the direction with another method ;) Which words in a title should be capitalized? Are there any concrete rules that say which words (parts of speech) in a title should start with a capital letter? What would be a correct capitalization for the title of this question? How did this person gain possession of the Infinity Stones? How can I have a horizontally shaded frametitle in beamer? This question is similar to . I want to achieve the horizontal shading effect in the frametitle and when I use  \setbeamertemplate{frametitle}[horizontal shading] [left=red, right=white]   I get compilation errors:  LaTeX Error: Missing \begin{document}. [[]   Vertical shading seems to work just fine.