Set values on the diagonal of pandas.DataFrame

Question

I have a pandas dataframe I would like to se the diagonal to 0

import numpy
import pandas

df = pandas.DataFrame(numpy.random.rand(5,5))
df

Out[6]:
     0           


        

Answer 1

Using np.fill_diagonal(df.values, 1) Is the easiest, but you need to make sure your columns all have the same data type I had a mixture of np.float64 and python floats and it would only effect the numpy values. to fix you have to cast everything to numpy.