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numpyfill

filling numpy array with mean values form data

Why does this produce an array of zeros for q, instead of the actualy value or err which is 0.0159? 

errors=np.loadtxt('data').T[2]
err=np.mean(errors)
q=np.empty(99)
q.fill(err)
Solution

  • You haven't shown us enough code to reproduce the problem. Normally, q.fill would work as expected:

    import numpy as np

err = 0.0159
q = np.empty(9)
q.fill(err)
print(q)
# [ 0.0159  0.0159  0.0159  0.0159  0.0159  0.0159  0.0159  0.0159  0.0159]

    However, (taking a stab in the dark), if q has an integer dtype, then q.fill(0.0159) would floor 0.0159 down to the nearest int and thus q would become filled with zeros:

    err = 0.0159
q = np.empty(9, dtype='int')
q.fill(err)
print(q)
# [0 0 0 0 0 0 0 0 0]