[Numpy-discussion] Data types in Numerical Python

[Linda Seltzer]

> Here is an example that works for any working numpy installation:
>
> import numpy as npy
> npy.zeros((256, 256))
This suggestion from David did work so far, and removing the other import
line enabled the program to run.
However, the data types the program used as defaults for variables has
changed, and now I am getting error messages about data types.  It seems
that some variables are getting a default designation as floats.  Before I
installed numpy and needed 2-D arrays, the program was working with the
default types, and I did not have to specify types.
Is there a clear tutorial that describes a means to assign data types for
each variable as in C, so that I don't obtain error messages about data
types?
Because I am simulating code for a DSP processor, the data types I need
are unsigned bytes, unsigned 32-bit ints, and signed 32-bit ints.  In some
cases I can use unsigned and signed 16-bit ints.
Also, what data types are valid for use with local operations such as
exclusive or?