Convert int arrays to string arrays to numpy without truncation

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Trying to convert int arrays to string arrays in numpy

In [66]: a=array([0,33,4444522])
In [67]: a.astype(str)
Out[67]:
array(['0', '3', '4'],
      dtype='|S1')

Not what I intended

In [68]: a.astype('S10')
Out[68]:
array(['0', '33', '4444522'],
      dtype='|S10')

This works but I had to know 10 was big enough to hold my longest string. Is there a way of doing this easily without knowing ahead of time what size string you need? It seems a little dangerous that it just quietly truncates your string without throwing an error.


Again, this can be solved in pure Python:

>>> map(str, [0,33,4444522])
['0', '33', '4444522']

Or if you need to convert back and forth:

>>> a = np.array([0,33,4444522])
>>> np.array(map(str, a))
array(['0', '33', '4444522'],
      dtype='|S7')