Why Zsh `time` not work for some commands?
`time echo` got no output
It seems to me that tuples are just as elementary as sets. Can tuples be reduced to sets? A natural number multiplied by some integer results in a number with only ones and zeros I recently solved a , which says that,     A positive integer can be multiplied with another integer resulting in   a positive integer that is composed only of one and zero as digits.   How can I prove that this is true(currently I assume that it is). Also, is it possible to establish an upper bound on the length(number of digits) of the number generated? Double booked - User bookmarking question recorded twice In this  one user is shown as having bookmarked  twice:  This doesn't appear to be the same question as:  or  though it's certainly possible that the cause is the same. How do I inspect the view hierarchy in iOS? Simple prime number generator in Python Could someone please tell me what I'm doing wrong with this code? It is just printing 'count' anyway.  I just want a very simple prime generator (nothing fancy).   import math  def main():     count = 3     one = 1     while one == 1:         for x in range(2, int(math.sqrt(count) + 1)):             if count % x == 0:                  continue             if count % x != 0:                 print count          count += 1 biblatex: multiple bibliographies categorised by different .bib files biblatex supports multiple bibliographies by looking up the 1) entry type, 2) keyword, or 3) category.  This is all fine, but in the use case of primary sources and secondary sources: 1) the 'type' method doesn't work, 2) it is quite tedious to key in the 'primary' and 'secondary' keywords for each .bib entry, and 3) declaring the sorting by category would entail typing all the primary keys in the document.  So, if I'm storing all my primary bib entries in one .bib file, and secondary one in another, is there a bit to tell biblatex to assign a keyword or category automatically to all the entries from that bib file as it imports them?  Done this way, entries can be easily swapped to and from the primary and secondary .bib files without fiddling individual keywords, and I don't have to type out all the primary and/or secondary entries into categories in each document. Book for proof writing I am pretty sure that this is such a stupid, stupid question, but how do you prove that $d_2(x,y)={|x-y|\over {1+|x-y|}}$ satisfying the third condition to be a metric, which is the triangle inequality.   I know that I should really be able to do this, but I just can't, I keep seeing a contradiction. Please help me. Show that every prime $p>3$ is either of the form $6n+1$ or of the form $6n+5$ Show that every prime $p&gt;3$ is either of the form $6n+1$ or of the form $6n+5$, where $n=0,1,2, \dots$ The question is (from Topology without tears) that: Let $(X,d)$ be a metric space and $\tau$ the corresponding topology on $X$. Fix $a \in X$. Prove that the map $f:(X,\tau) \rightarrow \mathbb{R}$ defined by $f(x) = d(a,x)$ is continuous.  My first attempt was that let an open ball, $B_{\epsilon}(a)\subset \mathbb{R}$ and show that $f^{-1}(B_{\epsilon}(a)) \subset \tau$. Since $f(x) = d(a,x)$, $f^{-1}(B_{\epsilon}(a))=B_{\epsilon}(a) \in \tau$.   I am pretty sure the last sentence is wrong. I am not sure if every open ball is an open set in topology induced by metric space.  Please give me some hint and direction. Thanks How widely-accepted is "What do you got?" to Americans? Watching , I noticed that Melanie Griffith twice asked    I recognise this as an American construction which sounds strange to me — Brits invariably say either "What have you got?" or "What do you have?". But I'd be interested to know if it's considered "normal" by most/all Americans, or if it's regionally or otherwise restricted. Return multiple values from a SQL Server function How would I return multiple values (say, a number and a string) from a user-defined function in SQL Server? Given the following code (that doesn't work):  while True:     #snip: print out current state     while True:         ok = get_input("Is this ok? (y/n)")         if ok.lower() == "y": break 2 #this doesn't work :(         if ok.lower() == "n": break     #do more processing with menus and stuff   Is there a way to make this work? Or do I have do one check to break out of the input loop, then another, more limited, check in the outside loop to break out all together if the user is satisfied? In reading through the original GCM specification (), the composition of the 128 bit Initialization Vector as a concatenation of a 96b nonce and a 32b unsigned wrapping counter seems arbitrary and forces the scrambling pattern to repeat every 232 16-byte block.  Is the algorithm expected to be secure for significantly longer stream lengths if for example the IV were a 128b nonce XORed with a 64b or 128b counter, or are there known cryptanalysis issues that begin to arise? Any time I am inserting new point feature in QGIS, the Feature Attribute dialog box is popping up. Is there a way to prevent it? (I am willing to insert many points at once and this pop up box slows down the process). On a quantum scale the smallest unit is the , which is a discrete measure.  There several question that come to mind:   Does that mean that particles can only live in a discrete grid-like structure,  i.e. have to "magically" jump from one pocket to the next? But where are they in between? Does that even give rise to the old paradox that movement as such is impossible (e.g. )? Does the same hold true  for time (i.e. that it is discrete) - with all the ensuing paradoxes? Mathematically does it mean that you have to use difference equations instead of differential equations? (And sums instead of integrals?) From the point of view of the space metric do you have to use a discrete metric (e.g. the ) instead of good old Pythagoras?   Thank you for giving me some answers and/or references where I can turn to.  Update: I just saw this call for papers - it seems to be quite a topic after all: Is Reality Digital or Analog? FQXi Essay Contest, 2011. , , . One can find some pretty amazing papers over there. Show $\operatorname{Aut}(C_2 \times C_2)$ is isomorphic to $S_3=D_6$ I've heard a lot about the Undying Lands but I don't fully understand how they're different from Middle-earth and why only certain people/races are allowed to go there.  Can someone explain? Best explanation of Ruby blocks? Auto size image to page size in InDesign I've got an InDesign document with 100 A4 pages.   I've got 100 assets (a mixture of .jpg and .pdf files) and I want to place 1 per page. If an image is not the proportion of the A4 page I would like to get it as big as it can be on the page before it hits into the margin. Ex. if it's a portrait image it should be as large as it can be before hits the top/bottom margin. If it's a landscape image it should be as large as it can be before hits the left/right margin.   At the moment I'm dragging each file across and resizing them manually. Is it possible just drop them on the page and get them auto resized ?