TypeError: ufunc 'multiply' did not contain a loop with signature matching types dtype('S32')

"TypeError: ufunc 'multiply' did not contain a loop with signature matching types dtype('S32')"

If you create an array of numpy and then do an operation.

>>> a = numpy.array(datingLabels)

>>> a

array(['3', '2', '1', '1', '1', '1', '3', '3', '1', '3', '1', '1', '2',

       '1', '1', '1', '1', '1', '2', '3', '2', '1', '2', '3', '2', '3',

       '2', '3', '2', '1', '3', '1', '3', '1', '2', '1', '1', '2', '3',

       '3', '1', '2', '3', '3', '3', '1', '1', '1', '1', '2', '2', '1',

       ...

       '3', '1', '3', '2', '2', '2', '2', '2', '2', '2', '2', '2', '2',

       '2', '2', '3', '2', '2', '2', '2', '2', '1', '3', '3', '3'], 

      dtype='|S1')

>>> 15.0*a

the following error may appear.

Traceback (most recent call last):

   File "<stdin>", line 1, in <module>

TypeError: ufunc 'add' did not contain a loop with signature matching types dtype('S32') dtype('S32') dtype('S32')

or

Traceback (most recent call last):

  File "<stdin>", line 1, in <module>

TypeError: ufunc 'multiply' did not contain a loop with signature matching types dtype('S32') dtype('S32') dtype('S32')

In this case, dtype is a problem that does not match.

The data types of numpy are listed below and in the link.

https://docs.scipy.org/doc/numpy-1.9.1/user/basics.types.html

To solve the above problem, change the dtype or insert it at the time of creation.

>>> a = numpy.array(datingLabels, dtype=numpy.int32)

>>> a

array([3, 2, 1, 1, 1, 1, 3, 3, 1, 3, 1, 1, 2, 1, 1, 1, 1, 1, 2, 3, 2, 1, 2,

       3, 2, 3, 2, 3, 2, 1, 3, 1, 3, 1, 2, 1, 1, 2, 3, 3, 1, 2, 3, 3, 3, 1,

       1, 1, 1, 2, 2, 1, 3, 2, 2, 2, 2, 3, 1, 2, 1, 2, 2, 2, 2, 2, 3, 2, 3,

       ...

       2, 3, 2, 2, 2, 2, 2, 1, 3, 3, 3], dtype=int32)

>>> a*15.0

array([ 45.,  30.,  15.,  15.,  15.,  15.,  45., 45.,  15.,  45.,  15.,

       ...

      45.,  30.,  30.,  30.,  30.,  30.,  15.,  45.,  45.,  45.])

so, It can be confirmed that the operation is normally performed.