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How to use filter, map, and reduce in Python 3
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352
You can read about the changes in What's New In Python 3.0. You should read it thoroughly when...
Create Git branch with current changes
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730
If you hadn't made any commit yet, only (1: branch) and (3: checkout) would be enough.
Or, in o...
How can I convert NSDictionary to NSData and vice versa?
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363
NSDictionary -> NSData:
NSData *myData = [NSKeyedArchiver archivedDataWithRootObject:myDi...
What do ellipsis […] mean in a list?
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113
It means that you created an infinite list nested inside itself, which can not be printed. p co...
Split column at delimiter in data frame [duplicate]
...me.
I added a "x|y" line to avoid ambiguities:
df <- data.frame(ID=11:13, FOO=c('a|b','b|c','x|y'))
foo <- data.frame(do.call('rbind', strsplit(as.character(df$FOO),'|',fixed=TRUE)))
Or, if you want to replace the columns in the existing data.frame:
within(df, FOO<-data.frame(do.call('r...
Visual Studio 2010 - recommended extensions [closed]
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39 Answers
39
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“Inner exception” (with traceback) in Python?
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138
Python 2
It's simple; pass the traceback as the third argument to raise.
import sys
class MyE...
How to count the number of true elements in a NumPy bool array
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3 Answers
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Multidimensional Array [][] vs [,] [duplicate]
...uble[5][];
x[0] = new double[10];
x[1] = new double[5];
x[2] = new double[3];
x[3] = new double[100];
x[4] = new double[1];
Because each entry in the array is a reference to an array of double. With a jagged array, you can do an assignment to an array like you want in your second example:
x[0] =...
What does $@ mean in a shell script?
...drea Bergonzo
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answered Apr 3 '12 at 13:30
HarHar
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