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How do I replace NA values with zeros in an R dataframe?
I have a data frame and some columns have NA values.
21 Answers
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What are the advantages of using nullptr?
This piece of code conceptually does the same thing for the three pointers (safe pointer initialization):
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What is the most efficient string concatenation method in python?
Is there any efficient mass string concatenation method in Python (like StringBuilder in C# or StringBuffer in Java)? I found following methods here :
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Cocoa: What's the difference between the frame and the bounds?
UIView and its subclasses all have the properties frame and bounds . What's the difference?
12 Answers
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Is “argv[0] = name-of-executable” an accepted standard or just a common convention?
When passing argument to main() in a C or C++ application, will argv[0] always be the name of the executable? Or is this just a common convention and not guaranteed to be true 100% of the time?
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How to remove leading zeros from alphanumeric text?
I've seen questions on how to prefix zeros here in SO. But not the other way!
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What's the simplest way to test whether a number is a power of 2 in C++?
I need a function like this:
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Are members of a C++ struct initialized to 0 by default?
I have this struct :
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How to split a string and assign it to variables
In Python it is possible to split a string and assign it to variables:
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How do I convert a numpy array to (and display) an image?
I have created an array thusly:
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