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What is the fastest integer division supporting division by zero no matter what the result is?

...x, int y) { y += y == 0; return x/y; } The compiler basically recognizes that it can use a condition flag of the test in the addition. As per request the assembly: .globl f .type f, @function f: pushl %ebp xorl %eax, %eax movl %esp, %ebp movl 12(%...
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mongo group query how to keep fields

...are accumulated/funneled/reduced) doesn't make so much sense even theoretically. However, sorting before hand is actually inefficient compared to sorting each group within themselves since sorting algorithms are more complex than O(n). I wish there would be better ways in MongoDB. ...
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Variable interpolation in the shell

I have a variable called filepath=/tmp/name . 3 Answers 3 ...
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How can I get a precise time, for example in milliseconds in Objective-C?

... Actually this is precise enough for the general use case. – logancautrell Jul 2 '12 at 12:30 4 ...
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Mailto links do nothing in Chrome but work in Firefox?

...omputer. I know at work, it will run thunderbird; if they have outlook installed it may run outlook, etc. Personally, it did not run gmail by default, I had to set it up that way. – kennypu Jul 14 '13 at 1:55 ...
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Preferred method to store PHP arrays (json_encode vs serialize)

...ciative array of data in a flat file for caching purposes. I might occasionally come across the need to convert it to JSON for use in my web app but the vast majority of the time I will be using the array directly in PHP. ...
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How to set environment variables in Python?

I need to set some environment variables in the Python script and I want all the other scripts that are called from Python to see the environment variables' set. ...
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How to reshape data from long to wide format

... The reshape comments and similar argument names aren't all that helpful. However, I have found that for long to wide, you need to provide data = your data.frame, idvar = the variable that identifies your groups, v.names = the variables that will become multiple columns in wide f...
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How can I setup & run PhantomJS on Ubuntu?

... to add one additional symlink to /usr/bin/, and I did direct symlinks for all 3 - see below. I'm installing on Ubuntu server Natty Narwhal. This is exactly what I did. cd /usr/local/share sudo wget https://bitbucket.org/ariya/phantomjs/downloads/phantomjs-1.9.7-linux-x86_64.tar.bz2 sudo tar xjf ...
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How to create a zip archive of a directory in Python?

...e. The documentation tells you what functions are available, but doesn't really explain how you can use them to zip an entire directory. I think it's easiest to explain with some example code: #!/usr/bin/env python import os import zipfile def zipdir(path, ziph): # ziph is zipfile handle f...