Writing a matrix to a text file in python

When writing to a text file using the following code it shows following output :-

import numpy as np

a = np.random.randint(1, 1000, size =(100, 30),dtype='int64')
print(a)
np.savetxt('filename.txt', a)

Output :-

5.100000000000000000e+01 1.530000000000000000e+02 7.290000000000000000e+02 4.180000000000000000e+02 6.700000000000000000e+02 4.410000000000000000e+02 6.230000000000000000e+02 1.970000000000000000e+02 8.120000000000000000e+02 5.770000000000000000e+02 3.790000000000000000e+02 8.970000000000000000e+02 5.890000000000000000e+02 6.140000000000000000e+02 9.500000000000000000e+01

I want 51 153 and son on as values in text file instead of these.

>Solution :

You need to specify format (fmt) if you are not happy with numpy.savetxt‘s default %.18e. Use %d if you just want simple integers, consider following simple example

import numpy as np
arr = np.array([[51,153],[729,51]])
np.savetxt('array.txt', arr, fmt='%d')

creates array.txt with following content

51 153
729 51