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How to check whether a pandas DataFrame is empty?

... This seems like a shame, since you need to know that df is a pd.DataFrame. I'd like to know the motivation for not implementing bool() on pd.DataFrame. – Quant Feb 14 '14 at 16:55 ...
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Finding three elements in an array whose sum is closest to a given number

...A 2 , ..., A n , including negatives and positives, and another integer S. Now we need to find three different integers in the array, whose sum is closest to the given integer S. If there exists more than one solution, any of them is ok. ...
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Centering a background image, using CSS

...the server to do it, but used an imagehosting site, but still check it out now – X10nD Apr 15 '10 at 8:03  |  show 5 more comments ...
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How do I focus on one spec in jasmine.js?

... //... }) it('function 2', function() { //... } }) Now you can run just the whole spec by this url http://localhost:8888?spec=MySpec and a the first test with http://localhost:8888?spec=MySpec+function+1 ...
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How is “int* ptr = int()” value initialization not illegal?

... @NeilG: This stays the same in C++11, though there is now also a nullptr, which you can use instead of 0 or NULL in new code. – Jerry Coffin Nov 9 '11 at 23:02 ...
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What does the function then() mean in JavaScript?

...call takes a callback function that is executed when the server responds. Now of course the more levels of nesting we have, the harder the code is to read, debug, maintain, upgrade, and basically work with. This is generally known as callback hell. Also, if we needed to handle errors, we need to po...
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Hash collision in git

... hex character string... that's 4 bits per character times 40... 160 bits. Now we know 10 bits is approximately 1000 (1024 to be exact) meaning that there are 1 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 different SHA-1 hashes... 1048. What is this equivalent of? Well the Moon i...
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Install gitk on Mac

Does anyone know how to install gitk on Mac? 13 Answers 13 ...
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git push to specific branch

...push commands and have them do whatever you want. Which is great, if you know what you want and how to spell that in Git-Ese, but you're new to git! :-) In your case, Petr Mensik's answer is the (well, "a") right one. Here's why: The command git push remote roots around in your .git/config file ...
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test if event handler is bound to an element in jQuery [duplicate]

...ution but seems effective enough! The second time you ‘click’ you can know with certainty that it will not create a duplicate binding. I therefore use die() or unbind() like this: $("#someid").die("click").live("click",function(){... or $("#someid").unbind("click").bind("click",function(){....