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Applying a function to every row of a table using dplyr?
When working with plyr I often found it useful to use adply for scalar functions that I have to apply to each and every row.
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What is the difference between 0.0.0.0, 127.0.0.1 and localhost?
I am using Jekyll and Vagrant on my mac. I found that Jekyll server will bind to 0.0.0.0:4000 instead of 127.0.0.1:4000 . Also gem server will bind to this address by default. I can still visit it via http://localhost:port . But for Jekyll , it seems that the default setting (e.g. 0.0....
How can I find the number of days between two Date objects in Ruby?
How can I find the number of days between two Date objects?
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What is the >>>= operator in C?
Given by a colleague as a puzzle, I cannot figure out how this C program actually compiles and runs. What is this >>>= operator and the strange 1P1 literal? I have tested in Clang and GCC. There are no warnings and the output is "???"
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How to take column-slices of dataframe in pandas
I load some machine learning data from a CSV file. The first 2 columns are observations and the remaining columns are features.
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Open Redis port for remote connections
I can ping pong Redis on the server:
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Matplotlib scatter plot with different text at each data point
I am trying to make a scatter plot and annotate data points with different numbers from a list.
So, for example, I want to plot y vs x and annotate with corresponding numbers from n .
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Is it correct to use JavaScript Array.sort() method for shuffling?
I was helping somebody out with his JavaScript code and my eyes were caught by a section that looked like that:
12 Answers
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How do I calculate percentiles with python/numpy?
Is there a convenient way to calculate percentiles for a sequence or single-dimensional numpy array?
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Are Javascript arrays sparse?
That is, if I use the current time as an index into the array:
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