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jQuery: count number of rows in a table
... edited Aug 13 '11 at 19:15
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answered Jul 19 '09 at 14:05
tvanfossontvanfosso...
count the frequency that a value occurs in a dataframe column
...ydata.org/pandas-docs/stable/groupby.html
Also 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:
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Is there a performance difference between a for loop and a for-each loop?
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Python - When to use file vs open
...uctor is new in Python 2.2. The previous spelling, open(), is retained for compatibility, and is an alias for file()." Since I decided to RTFM ten years ago, and became very fond the the unification of types and classes, I never used open() again. Moreover, I still feel that the type constructor is...
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