convert numpy.ndarray object to float

*Here is object dtype numpy.ndarray

print(oneD_pt.dtype, type(oneD_pt), oneD_pt)
> object <class 'numpy.ndarray'> [3 2 1 2 2] 

* convert float dtype numpy.ndarray

oneD_pt=oneD_pt.astype('float')

print(oneD_pt.dtype, type(oneD_pt), oneD_pt)

> float64 <class 'numpy.ndarray'> [3. 2. 1. 2. 2.]

thank you.