What is the difference between size and count in pandas?

Question

That is the difference between groupby(\"x\").count and groupby(\"x\").size in pandas ?

Does size just exclude nil ?

Answer 1

Just to add a little bit to @Edchum's answer, even if the data has no NA values, the result of count() is more verbose, using the example before:

grouped = df.groupby('a')
grouped.count()
Out[197]: 
   b  c
a      
0  2  2
1  1  1
2  2  3
grouped.size()
Out[198]: 
a
0    2
1    1
2    3
dtype: int64