Is there a parameter in matplotlib/pandas to have the Y axis of a histogram as percentage?

Question

I would like to compare two histograms by having the Y axis show the percentage of each column from the overall dataset size instead of an absolute value. Is that possible?

Answer 1

You can simplify the weighting using np.ones_like():

df["ColumnName"].plot.hist(weights = np.ones_like(df.index) / len(df.index))

• np.ones_like() is okay with the df.index structure
• len(df.index) is faster for large DataFrames