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Replace all 0 values to NA
I have a dataframe with some numeric columns. Some row has a 0 value which should be considered as null in statistical analysis. What is the fastest way to replace all the 0 value to NULL in R?
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Javascript calculate the day of the year (1 - 366)
How do I use javascript to calculate the day of the year, from 1 - 366? For example:
22 Answers
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Undefined method 'task' using Rake 0.9.0
I just updated Rake to the latest version ( 0.9.0.beta.4 ) and the rake command ends up with the following error message:
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Why is a round-trip conversion via a string not safe for a double?
Recently I have had to serialize a double into text, and then get it back. The value seems to not be equivalent:
3 Answers
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Apply pandas function to column to create multiple new columns?
How to do this in pandas:
13 Answers
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Django Server Error: port is already in use
Restarting the Django server displays the following error:
16 Answers
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All falsey values in JavaScript
What are the values in JavaScript that are 'falsey' , meaning that they evaluate as false in expressions like if(value) , value ? and !value ?
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How do I print a double value without scientific notation using Java?
I want to print a double value in Java without exponential form.
14 Answers
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How to find the kth smallest element in the union of two sorted arrays?
This is a homework question. They say it takes O(logN + logM) where N and M are the arrays lengths.
17 Answers
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Is it possible to change only the alpha of a rgba background colour on hover?
I have a set of <a> tags with differing rgba background colours but the same alpha. Is it possible to write a single css style that will change only the opacity of the rgba attribute?
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