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Adding a column to a data.frame
...p <- as.factor(your.df$group)
no h_freq h_freqsq group
1 1 0.40998238 0.06463876 1
2 2 0.98086928 0.33093795 1
3 3 0.28908651 0.74077119 1
4 4 0.10476768 0.56784786 1
5 1 0.75478995 0.60479945 2
6 2 0.26974011 0.95231761 2
7 3 0.53676266 0.74370154...
cartesian product in pandas
...f1, df2,on='key')[['col1', 'col2', 'col3']]
Output:
col1 col2 col3
0 1 3 5
1 1 3 6
2 2 4 5
3 2 4 6
See here for the documentation: http://pandas.pydata.org/pandas-docs/stable/merging.html#brief-primer-on-merge-methods-relational-algebra
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How to use a decimal range() step value?
Is there a way to step between 0 and 1 by 0.1?
33 Answers
33
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Selecting pandas column by location
...t come to mind:
>>> df
A B C D
0 0.424634 1.716633 0.282734 2.086944
1 -1.325816 2.056277 2.583704 -0.776403
2 1.457809 -0.407279 -1.560583 -1.316246
3 -0.757134 -1.321025 1.325853 -2.513373
4 1.366180 -1.265185 -2.184617 0.881514
>>> df...
Why does changing 0.1f to 0 slow down performance by 10x?
...rap and resolve them using microcode.
If you print out the numbers after 10,000 iterations, you will see that they have converged to different values depending on whether 0 or 0.1 is used.
Here's the test code compiled on x64:
int main() {
double start = omp_get_wtime();
const float x[1...
What is a regular expression which will match a valid domain name without a subdomain?
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20 Answers
20
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Type-juggling and (strict) greater/lesser-than comparisons in PHP
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PHP's c...
Difference between break and continue statement
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answered Jan 20 '09 at 18:02
Xn0vv3rXn0vv3r
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Find indices of elements equal to zero in a NumPy array
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numpy.where() is my favorite.
>>> x = numpy.array([1,0,2,0,3,0,4,5,6,7,8])
>>> numpy.where(x == 0)[0]
array([1, 3, 5])
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Phonegap Cordova installation Windows
...ordova is absolutely horrible. All I'm trying to do is install PhoneGap 3.0 on my Windows environment but having no success.
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