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How to form tuple column from two columns in Pandas

... 208 Get comfortable with zip. It comes in handy when dealing with column data. df['new_col'] = li...
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How to initialize an array's length in JavaScript?

..., e.g. var data = []; var length = 5; // user defined length for(var i = 0; i < length; i++) { data.push(createSomeObject()); } share | improve this answer | follow...
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How do I calculate percentiles with python/numpy?

...y too. import numpy as np a = np.array([1,2,3,4,5]) p = np.percentile(a, 50) # return 50th percentile, e.g median. print p 3.0 This ticket leads me to believe they won't be integrating percentile() into numpy anytime soon. ...
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How to detect a Christmas Tree? [closed]

... 10 Answers 10 Active ...
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Perl build, unit testing, code coverage: A complete working example

... 105 It took me a while and it also took me taking small snippets from a number of different sources...
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Is it correct to use JavaScript Array.sort() method for shuffling?

... 110 It's never been my favourite way of shuffling, partly because it is implementation-specific as y...
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Add a common Legend for combined ggplots

... 108 Update 2015-Feb See Steven's answer below df1 <- read.table(text="group x y gro...
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Remove outline from select box in FF

...he color of the dotted border. So say if you do... select { color: rgba(0,0,0,0); } Firefox will render the dotted border transparent. But of course your text will be transparent too! So we must somehow display the text. text-shadow comes to the rescue: select { color: rgba(0,0,0,0); text-...
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What's the fastest way to merge/join data.frames in R?

...he first example sqldf is 3x slower than data.table and in the second its 200x faster than plyr and 100 times faster than data.table. Below we show the input code, the output timings for the merge and the output timings for the aggregate. Its also worthwhile noting that sqldf is based on a databa...
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How can I sort arrays and data in PHP?

...te a comparison function. That function takes two elements and must return 0 if these elements are considered equal, a value lower than 0 if the first value is lower and a value higher than 0 if the first value is higher. That's all that's needed: function cmp(array $a, array $b) { if ($a['foo']...