python - Pandas: Sorting columns by their mean value -

i have dataframe in pandas, sort columns (i.e. new dataframe, or view) according mean value of columns (or e.g. std value). documentation talks sorting label or value, not find on custom sorting methods.

how can this?

you can use mean dataframe method , series sort_values method:

in [11]: df = pd.dataframe(np.random.randn(4,4), columns=list('abcd'))  in [12]: df out[12]:                   b         c         d 0  0.933069  1.432486  0.288637 -1.867853 1 -0.455952 -0.725268  0.339908  1.318175 2 -0.894331  0.573868  1.116137  0.508845 3  0.661572  0.819360 -0.527327 -0.925478  in [13]: df.mean() out[13]:    0.061089 b    0.525112 c    0.304339 d   -0.241578 dtype: float64  in [14]: df.mean().sort_values() out[14]: d   -0.241578    0.061089 c    0.304339 b    0.525112 dtype: float64 

then can reorder columns using reindex_axis:

in [15]: df.reindex_axis(df.mean().sort_values().index, axis=1) out[15]:           d                 c         b 0 -1.867853  0.933069  0.288637  1.432486 1  1.318175 -0.455952  0.339908 -0.725268 2  0.508845 -0.894331  1.116137  0.573868 3 -0.925478  0.661572 -0.527327  0.819360 

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note: in earlier versions of pandas, sort_values used order, order deprecated part of 0.17 more consistent other sorting methods.