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Function Pointers in Java
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The Java idiom for function-pointer-like functionality is an an anonymous class implementing an...
Get nth character of a string in Swift programming language
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Missing Maven dependencies in Eclipse project
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How to pass optional arguments to a method in C++?
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edited May 25 '18 at 10:44
AustinWBryan
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Repeat each row of data.frame the number of times specified in a column
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Here's one solution:
df.expanded <- df[rep(row.names(df), df$freq), 1:2]
Result:
var1 var2
1 a d
2 b e
2.1 b e
3 c f
3.1 c f
3.2 c f
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im...
How do you get the magnitude of a vector in Numpy?
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220
The function you're after is numpy.linalg.norm. (I reckon it should be in base numpy as a prop...
Working with huge files in VIM
I tried opening a huge (~2GB) file in VIM but it choked. I don't actually need to edit the file, just jump around efficiently.
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What's the difference between lists and tuples?
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How to dynamically compose an OR query filter in Django?
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You could chain your queries as follows:
values = [1,2,3]
# Turn list of values into list of Q...
Deleting lines from one file which are in another file
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grep -v -x -f f2 f1 should do the trick.
Explanation:
-v to select non-matching lines
-x to match whole lines only
-f f2 to get patterns from f2
One can instead use grep -F or fgrep to match fixed strings from f2 rather than patterns (...