RuntimeWarning: divide by zero encountered in log

Question

I am using numpy.log10 to calculate the log of an array of probability values. There are some zeros in the array, and I am trying to get around it using

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Answer 1

I solved this by finding the lowest non-zero number in the array and replacing all zeroes by a number lower than the lowest :p

Resulting in a code that would look like:

def replaceZeroes(data):
  min_nonzero = np.min(data[np.nonzero(data)])
  data[data == 0] = min_nonzero
  return data

 ...

prob = replaceZeroes(prob)
result = numpy.where(prob > 0.0000000001, numpy.log10(prob), -10)

Note that all numbers get a tiny fraction added to them.