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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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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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What's the (hidden) cost of Scala's lazy val?
One handy feature of Scala is lazy val , where the evaluation of a val is delayed until it's necessary (at first access).
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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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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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Django Server Error: port is already in use
Restarting the Django server displays the following error:
16 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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How to debug Lock wait timeout exceeded on MySQL?
In my production error logs I occasionally see:
11 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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Modify SVG fill color when being served as Background-Image
Placing the SVG output directly inline with the page code I am able to simply modify fill colors with CSS like so:
16 Answe...