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count the frequency that a value occurs in a dataframe column
...o value_counts() as @DSM has commented, many ways to skin a cat here
In [38]:
df['a'].value_counts()
Out[38]:
b 3
a 2
s 2
dtype: int64
If you wanted to add frequency back to the original dataframe use transform to return an aligned index:
In [41]:
df['freq'] = df.groupby('a')['a'].tra...
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Mocking member variables of a class using Mockito
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Add a prefix string to beginning of each line
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edited Oct 25 '18 at 22:35
PhysicalChemist
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Nick Craver♦Nick Craver
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edited Jul 28 '12 at 8:24
PresleyDias
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180
I currently study such problems -- classification, nearest neighbor searching -- for music info...
Get the closest number out of an array
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218
ES5 Version:
var counts = [4, 9, 15, 6, 2],
goal = 5;
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...ML5 you can neglect it.
– Cris
Feb 18 '16 at 5:34
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