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Convert boolean result into number/integer
I have a variable that stores false or true , but I need 0 or 1 instead, respectively. How can I do this?
17 Answers...
Delete the first three rows of a dataframe in pandas
I need to delete the first three rows of a dataframe in pandas.
7 Answers
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How to read the content of a file to a string in C?
What is the simplest way (least error-prone, least lines of code, however you want to interpret it) to open a file in C and read its contents into a string (char*, char[], whatever)?
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Numpy: Get random set of rows from 2D array
I have a very large 2D array which looks something like this:
7 Answers
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Remove rows with all or some NAs (missing values) in data.frame
I'd like to remove the lines in this data frame that:
16 Answers
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Why is printing to stdout so slow? Can it be sped up?
I've always been amazed/frustrated with how long it takes to simply output to the terminal with a print statement. After some recent painfully slow logging I decided to look into it and was quite surprised to find that almost all the time spent is waiting for the terminal to process the results.
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Avoid trailing zeroes in printf()
I keep stumbling on the format specifiers for the printf() family of functions. What I want is to be able to print a double (or float) with a maximum given number of digits after the decimal point. If I use:
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Understanding how recursive functions work
As the title explains I have a very fundamental programming question which I have just not been able to grok yet. Filtering out all of the (extremely clever) "In order to understand recursion, you must first understand recursion." replies from various online threads I still am not quite getting it....
How to smooth a curve in the right way?
Lets assume we have a dataset which might be given approximately by
9 Answers
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How to clear the canvas for redrawing
After experimenting with composite operations and drawing images on the canvas I'm now trying to remove images and compositing. How do I do this?
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