I was wondering if it is correct to use the expression if to speak about. For example, suppose we wanted talk about one subject and then change it to another one:     These are very dangerous mountains, and a lot of preparation is needed. If to speak about salary for this kind of work, it is very…
I am pretty much sure that for native speakers the issue I am going to bring up might look as an uncalled question as they can easily figure out which form of a verbal part of speech should be used, be it a gerund, an infinitive, or a bare infinitive. However, it can be pretty much misleading for a foreigner because the same construction works differently with different words and I don’t see a logical explanation. For example:  The purpose of this article is to analyze the issue…  My hobby is reading. One may assume, and many foreigners really come to this conclusion, that it’s OK to switch the “gerund” and “infinitive” as the meaning will stay the same, that is:  The purpose of this article is analyzing the issue… (same as 1 above)  My hobby is to read. (same as 2 above)   However, as I was told, this assumption is erroneous. Another example: His task was watching after them. (not good) His task was to watch after them. Is there any principle which governs the choice of the right form in such cases?
The  of March 01, 2013 put it's distance at 14 hrs 04 mins 23 secs of light-travel time from Earth. A  (earlier today) tweet says it is 14 hrs 04 mins 22 secs of light-travel time from Earth. An  tweet put it still further out at 14 hrs 04 mins 25 secs of light-travel time.  The Voyager 2 tweets on Voyager 1's proximity to Earth too has reduced similarly to  earlier today from  reported on Feb 28 2013  It could quite simply be a typo ... If not a typo then my curiosity is piqued; I was under the impression the Voyagers are outbound from the Solar System now without any major in-system activities now.   How is it the Voyagers are closer to Earth than before? Is it possible to create an iron door which responds to levers on both sides Combinatorics identity question Let $z \in \Gamma (R)$ where this is the upper semi circle centred at the origin with radius $R&gt;1$. Let $z=x+iy$ with $x \in \mathbb{R}$ and $y \geq 0$. So   $$|e^{i \lambda z}|=|e^{i \lambda z}| |e^{- \lambda y}|= |e^{- \lambda y}|$$  where $\lambda \in \mathbb{R}^{+}$.  How can the last equality possibly be true? Well, I have come to understand persons with the following traits will be usually be Sorted to Slytherin   Resourcefulness  Cunning Ambition Leadership Qualities Self-Preservation Determination  Cleverness Fraternity  Power   On which trait(s) was Snape Sorted into Slytherin?  One more point: Lily Evans was Sorted before Snape, and when she was placed in Gryffindor, obviously Snape wanted to be in Gryffindor too, because Lily is his only friend.   So why is he Sorted into Slytherin? Is there a stronger reason for the Sorting Hat to override his preference and Sort him into Slytherin? Invariance of a maximally entangled state under unitary operation $U \otimes U^\dagger$ I have a Schengen visa valid from 19/07/2016 to 10/08/2016. But the duration of stay is 7 days only.  I want to stay for 6 days more, for a total of 14 days. And my flight includes travel from a Schengen state to another. Why is the plural of "basis" "bases" and not "baseis"? Looking at the , it indicates that the plural is either bases or baseis.  It looks like the rare  comes from the Greek, but the common  just refers back to basis and that does not explain the plural etymology.  Is there a standard rule at work here, or is this just an exceptional case that arose over time by convention? Java: Cannot find symbol? I need to host several Apache virtual hosts with SSL from a single IP.  Now - I understand that because SSL wraps around the HTTP request, there's no way to know which host is being requested until a public key has been sent to the client first. This essentially breaks the possibility of SSL virtual hosts using a standard SSL certificate.  I have obtained a Unified Communications Certificate (UCC), otherwise known as a Subject Alternative Name (SAN) certificate. This allows me to serve the same certificate for multiple domains.  I would like this to be the certificate served by Apache for any SSL request - and then have Apache resolve the virtual host as usual, once the encryption has been established.  How should I configure Apache for this? I have tried to research how this can be done, but all I can find are quotes which say that it is possible, but no specifics:    wiki.apache.org/httpd/NameBasedSSLVHostsWithSNI     While Apache can renegotiate the SSL   connection later after seeing the   hostname in the request (and does),   that's too late to pick the right   server certificate to use to match the   request hostname during the initial   handshake, resulting in browser   warnings/errors about certificates   having the wrong hostname in them.   serverfault.com/questions/48334/apache-virtual-hosts-with-ssl     Incidentally, it is possible to have   multiple SSL-secured named virtual   hosts on a single IP address - I do it   on my website - but it produces all   sorts of warnings in the Apache logs,   and certificate warnings in the   browser. I certainly wouldn't   recommend it for a production site   that needs to look clean.   -David Jul 31 at 4:58   www.digicert.com/subject-alternative-name.htm     Virtual Host Multiple SSL sites on a single   IP address. Hosting multiple   SSL-enabled sites on a single server   typically requires a unique IP address   per site, but a certificate with   Subject Alternative Names can solve   this problem. Microsoft IIS 6 and   Apache are both able to Virtual Host   HTTPS sites using Unified   Communications SSL, also known as SAN   certificates.     Please help. Show there exists $g:(0,1)\to\mathbb{R}^2$ such that $h\circ g$ constant, $g$ continuously differentiable and $g$ injective Does the Divergence Theorem Work on a Surface? The divergence theorem in $\mathbb{R}^3$ says that the integral of the divergence of a vector field over a solid $\Omega$ in $\mathbb{R}^3$ equals the flux through the surface of $\Omega$ denoted by $\partial \Omega$.   My question is that can you use the divergence theorem in $\mathbb{R}^3$ where you're integrating the divergence of a vector field over a surface $S$ in $\mathbb{R}^3$ to get the flux through the edges ($\partial S$) of the surface? So if the surface $S$ is closed in $\mathbb{R}^3$ such as a sphere, then clearly $\partial S = 0$ so the integral of the divergence over this particular $S$ is $0$? If I take r as the radial vector of the moving object and v as the velocity vector of the moving object in central force field.   Then r should be perpendicular to r×v . So that depicts that r.(r×v) = 0 . So how does this say that the particle is lying on a constant plane ? Do I need a US visa to transit (or layover) through an American airport? I'm using a flow to set a field to a certain value (01, 02, 03) depending on the value of another field on the same record. I initially wanted to do it with process builder but because of the mapping it seems I would need three 'criteria nodes' or a formula field. Furthermore, it seems Salesforce is recommending using flows instead of process builder for before update actions as it is faster.  The problem with Flows is that I found a way to trigger it when the record is new or updated but not when the specific field is changed so it triggers every time the whole record is updated even when the field stay the same.  On Process Builder, you can use isChanged and then call the flow with specific record but that kinds of defeat the point of using flows for before Update.  So is there a possibility to do the same thing directly in flow ?  Thank you for the help ! In mathematics, we like talking about idempotent matrices. In a masters program that I am currently enrolled in, I have heard one professor pronounce it one way, and another professor pronounce it another way. The  explains it better than I could:  Is there a correct pronunciation for idempotent? Is it like omnipotent (om-nip-o-tent), so id-EMP-o-tent, or is it more like the two seperate words idem + potent I'd say EYE-dm-POT-nt, but then I speak Brit. Charles Matthews 07:57, 30 Jun 2004 (UTC) Ditto, but then I speak Australian ;) Dysprosia 08:01, 30 Jun 2004 (UTC) Actually the British is more like EYE-dm-PO-tnt, I guess. Charles Matthews I'd just like to pedantically point out that it would be pronounced i-DEM-po-tent because because syllable onsets are maximized. daesotho 20:33, 21 Oct 2004 (UTC) The American pronunciation puts primary stress on the second syllable ('dem') and secondary stress on the fourth syllable ('tence'). Could somebody more familiar with IPA than I am please add this to the article as an accepted pronunciation? My American dictionary says |ˈīdemˌpōtənt| for the adjective. I speak American (non-natively) and I wouldn't stress the second syllable for itempotence. My only question is, right now it says /ˌaɪdɪmˈpoʊtəns/ -- but can't it be stressed on the first syllable too? Should we add /'aɪdɪmˌpoʊtəns/ as an alternative? -- 87.160.141.177 (talk) 14:50, 3 June 2011 (UTC) And by the way I think it's silly giving a pronounciation guide as this is just imposing a particular accent. (For what it's worth I pronounce idempotent with a short 'i', as in the word 'id'). Alex Selby I agree with Alex Selby - the pronunciation guide should be extended to show the variation, or removed. Strictly, there's no reason for the first i to be long (neuter idem has a short first syllable in Latin), and I can't find any authoritative source which advocates the pronunciation given. Ms7821 (talk) 22:59, 15 July 2015 (UTC)  Is there a &quot;correct&quot; pronunciation for this word? How to show that the commutator subgroup is a normal subgroup How can I convert a string of bytes into an int in python?   Say like this: 'y\xcc\xa6\xbb'  I came up with a clever/stupid way of doing it:  sum(ord(c) &lt;&lt; (i * 8) for i, c in enumerate('y\xcc\xa6\xbb'[::-1]))   I know there has to be something builtin or in the standard library that does this more simply...  This is different from  for which you can use int(xxx, 16), but instead I want to convert a string of actual byte values.  UPDATE:  I kind of like James' answer a little better because it doesn't require importing another module, but Greg's method is faster:  &gt;&gt;&gt; from timeit import Timer &gt;&gt;&gt; Timer('struct.unpack("&lt;L", "y\xcc\xa6\xbb")[0]', 'import struct').timeit() 0.36242198944091797 &gt;&gt;&gt; Timer("int('y\xcc\xa6\xbb'.encode('hex'), 16)").timeit() 1.1432669162750244   My hacky method:  &gt;&gt;&gt; Timer("sum(ord(c) &lt;&lt; (i * 8) for i, c in enumerate('y\xcc\xa6\xbb'[::-1]))").timeit() 2.8819329738616943   FURTHER UPDATE:  Someone asked in comments what's the problem with importing another module. Well, importing a module isn't necessarily cheap, take a look:  &gt;&gt;&gt; Timer("""import struct\nstruct.unpack("&gt;L", "y\xcc\xa6\xbb")[0]""").timeit() 0.98822188377380371   Including the cost of importing the module negates almost all of the advantage that this method has. I believe that this will only include the expense of importing it once for the entire benchmark run; look what happens when I force it to reload every time:  &gt;&gt;&gt; Timer("""reload(struct)\nstruct.unpack("&gt;L", "y\xcc\xa6\xbb")[0]""", 'import struct').timeit() 68.474128007888794   Needless to say, if you're doing a lot of executions of this method per one import than this becomes proportionally less of an issue. It's also probably i/o cost rather than cpu so it may depend on the capacity and load characteristics of the particular machine. Given $S \in B(Y^{*}, X^{*})$, does there exist $T\in B(X,Y)$ such that $S=T^{*}$? "Eat" is to "feed" as "drink" is to what? I can say "I feed someone". Am I forced to say "I give someone a drink", or is there a single word for this (as in "I [verb] someone")?  Unfortunately my thesaurus can't really help me.