A single-variable continuous function that is irrational if and only if its argument is rational
No continuous function switches $\mathbb{Q}$ and the irrationals
Warning: mysql_fetch_* expects parameter 1 to be resource, boolean given error How do I determine the size of my array in C?   That is, the number of elements the array can hold? My roommate put a hunk of beef roast in the slow-cooker for a good 6 hours.  It's a fairly large sized slow-cooker, at least 8 quarts.  The meat was cooked through but very chewy, and I never remember my mom having that issue with a slow-cooker.  My roommate tends to put only enough water to get halfway up the side of the roast, and always uses a slow-cooker 'bag' (another thing my mom never did).  What advice can I offer them to get a better outcome? Let $f$ be a continuous function. If $f$ is uniformly continuous then it maps cauhy sequence into cauchy sequence. Is the converse true? That is if $f$ maps cauchy into cauchy gives the uniform continuity of $f$. I think it's no. Can suggest a counter example Is it feasible to build an index of prime factors? Would it be possible to break an RSA key, in for example 1 week of time, if the cracker have already spent X number of years building an index of primes by performing every permutation of existing prime keys up to $2^{2048}$?  I understand this would take an immense amount of time to do, but it would only be done once. Obviously, computing such an index would take a considerable amount of time and would have to be done with someone having the right amount of resource. Given the public key, you would be able to look up what the two primes are, and hence retrieve the private key instantly.  Breaking an 256 AES would then be easier, as AES keys are often generated using the RSA private key.  Would it be possible to build such an index? How long would that take in permutations and perhaps with the fastest computer in the world? Difference between @RemoteAction annotation and ? Is it a scam if the person only wants to deposit into my account, not make a withdrawal? Is my paper under review (or similar) for too long and if yes, how should I react? I submitted a paper to a journal, and I suspect that it is handled too slowly.   How can I decide whether my suspicion is correct? What handling times should I expect? Given some expected handling times, when should I act? How much leeway should I give? How should I act? Whom should I contact and what should I (roughly) write?   Note that I am interested on how I should approach this situation in general, and do not seek specific numbers for my specific situation. I am therefore looking for general answers that are independent of such factors as the field or individual journal (but mention them if they are relevant factors).  This is a canonical question on this topic as per . Due to its nature, it is rather broad and not exemplary for a regular question on this site. Please feel free to improve this question. TikZ \foreach loop with macro-defined list Browsing the internet from the command line How can I browse the Internet from the command line in Ubuntu? I read this story in the early 2000s, but it was a Chinese translation so the English version could be older.  The beginning is a bit like the Passengers movie: on a spaceship, a man woke up from stasis too early and found that he could not go back to sleep. So he has to spend his whole life on the spaceship, alone.  For some reason (technical or ethical), instead of waking other people up, he created a fantasy adventure story featuring a brave prince as a pastime. He did stories, and drawings all over the inside of the ship. Then he died, not knowing how people are going to respond to his work. How do you refer to a hyponym that is the same word as the hypernym? What word (or how do you phrase things) do you use when the ostensible word for the class is the same as the word for a subset of the class?  For example, in the United States, there are many brands of sugared, carbonated soft drink that one can buy: Coca-Cola (or Coke), Pepsi, RC Cola, Sprite, 7-Up, A&amp;W or Mug Root Beer, etc). The first two are kinds of 'coke' or 'cola' (but no one says 'cola').  , one asks for any type of such drink as 'coke'. How does one then ask for the particular kind of 'coke' that is 'Coke' (pronounced the same)? Does one reduplicate and say a 'Coke coke', does one repeat with emphasis (or without), does one use a different word like 'coca-cola' (co-cola), or what?  The (perceived) difficulty (surely those in the South are able to get the drink they want somehow) isn't limited to there. Where the drink is called 'soda', if you ask for a 'coke', you'll still sometimes have the choice among Coca-Cola, Pepsi, etc. "Can I have a Coke?" the response might be "Is Pepsi OK?". "Sure, Pepsi, Coke, whatever." You don't use 'cola', you just ask for the particular kind and hope the listener will help differentiate.   Given these multiple strategies for disambiguating, what do you do say to get a 'Coke' in the southern US? are there any other examples of a hypernym being the same as the hyponym, and so creating a disambiguation problem? Calculating the optimal number of bins for severely skewed data Should a student be penalized for using a theorem outside of the curriculum? How do I tell if ACR will work with my camera and how do I get the correct version for Photoshop? I am a beginner photographer with a Canon 7d and MacBook Pro. I'm not sure if Adobe camera Raw is compatible with either and really need advice on how to go about downloading the correct version. Indicator Function Here is  an excerpt from "All of Statistics" by Larry Wasserman (page 23):     Given an event A, define the indicator function of A by      $$ I_{A}(\omega)= \color{Red}{I(\omega \in A)} =\begin{cases}  1 &amp;  \text{ if } \omega \in A \\   0 &amp; \text{ if } \omega \notin A   \end{cases} $$   I am not convinced, referring to term colored red, with the notation here. Since this is a widely referred text, I would like to know that whether this is a typo or I am missing something here. Is there a name for this type of sentence structure: "She looks as though she's been poured into her clothes, and forgot to say 'when'"? Comedians seem to use phrases that employ this type of sentence structure - is there a name for it?  Examples of Groucho Marx's one liners seem to fit this pattern — and if memory serves, Emo Philips.       One morning I shot an elephant in my pajamas, how he got in my pajamas, I don't know.     I've had a perfectly wonderful evening, but this wasn't it. Use of "Proper" as a postpositive adjective I have an inkling that the following word usage is grammatically-correct; however, it is immensely difficult to search for confirmation, as all I receive for queries like &quot;Proper as an adjective&quot; are reams of results on &quot;Proper adjectives&quot;. The word itself I am using as a postpositive adjective, similar in form to the phrase &quot;time immemorial&quot;.  The shelter remains in name only; the shelter proper is in another town. Work in theory remained, although operations proper had mostly been outsourced.  Can anyone advise? Maximum and Minimum values for ints Lost email settings and no icon for Mail I've lost my Settings → Mail, Contacts, and Calendars on my iPhone 5.  No icon for Mail and no Mail settings.  How do I get it back?