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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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Is it better to call ToList() or ToArray() in LINQ queries?
I often run into the case where I want to eval a query right where I declare it. This is usually because I need to iterate over it multiple times and it is expensive to compute. For example:
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What is the difference between 127.0.0.1 and localhost
Assuming the following is defined in .../hosts :
6 Answers
6
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How to change the output color of echo in Linux
I am trying to print a text in the terminal using echo command.
30 Answers
30
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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 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?
10 Answers
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Custom numeric format string to always display the sign
Is there any way I can specify a standard or custom numeric format string to always output the sign, be it +ve or -ve (although what it should do for zero, I'm not sure!)
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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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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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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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