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Convert a row of a data frame to vector

... Might have been changed in the meantime, but today unlist allows dropping names: identical(unlist(df[1,], use.names = FALSE), as.numeric(df[1,])) (and btw df still is not a sensible name for a data.frame... ;-)) – Andri Signorell Sep 25 '1...
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Python Sets vs Lists

...move the object creation now. The setup phase of the timeit loops is only called once (docs.python.org/2/library/timeit.html#timeit.Timer.timeit). – Ellis Percival Sep 30 '14 at 10:09 ...
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Rails raw SQL example

... and then you'd need to call values on this PG::Result object to get the results array – jobwat Mar 26 '14 at 1:00 3 ...
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How to pull a random record using Django's ORM?

...['count'] random_index = randint(0, count - 1) return self.all()[random_index] share | improve this answer | follow | ...
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How to include package data with setuptools/distribute?

When using setuptools/distribute, I can not get the installer to pull in any package_data files. Everything I've read says that the following is the correct way to do it. Can someone please advise? ...
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window.close and self.close do not close the window in Chrome

...ec for window.close(): The close() method on Window objects should, if all the following conditions are met, close the browsing context A: The corresponding browsing context A is script-closable. The browsing context of the incumbent script is familiar with the browsing context A. Th...
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How to make a variadic macro (variable number of arguments)

... The reason for ## before VA_ARGS is that it swallows the preceding comma in case the variable-argument list is empty, eg. FOO("a") expands to printf("a"). This is an extension of gcc (and vc++, maybe), C99 requires at least one argument to be present in place of the elli...
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What does the brk() system call do?

...d load the "text" and "data" blocks into RAM starting at address zero (actually a little above address zero, so that the NULL pointer genuinely didn't point to anything) and set the break address to the end of the data segment. The first call to malloc would then use sbrk to move the break up and c...
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How to get datetime in JavaScript?

... Semantically, you're probably looking for the one-liner new Date().toLocaleString() which formats the date in the locale of the user. If you're really looking for a specific way to format dates, I recommend the moment.js library....
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printf format specifiers for uint32_t and size_t

...ng size_t to be the same as unsigned long (possibly 64 bits) when it's actually an unsigned int (32 bits). Try using %zu in both cases. I'm not entirely certain though. share | improve this answer ...