[Numpy-discussion] How to create structured char arrays?

[Bruce Southey]

Hi,
I think that I have resolved my issue down to creating a structured 
string array.
I am using numpy version '2.0.0.dev-3c338cb'.

Without a structured array, it should be a 2 by 2 array:
 >>> np.array([('a','b'),('c','d')])
array([['a', 'b'],
        ['c', 'd']],
       dtype='|S1')
 >>> np.array([('a','b'),('c','d')], dtype='a2')
array([['a', 'b'],
        ['c', 'd']],
       dtype='|S2')


It does not work as a structured array:
 >>> np.array([('a','b'),('c','d')], dtype=[('label','a2'), ('Value', 
'a4')])
array([('a', 'b'), ('c', 'd')],
       dtype=[('label', '|S2'), ('Value', '|S4')])

What is the correct dtype argument to use in this case?

Thanks
Bruce