python - Specifying default dtype for np.array(1.)

Question

Is there a way to specify default dtype that's used with constructs like np.array(1.)?

In particular I want np.array(1.) to be np.float32 and np.array(1) to be np.int32. Instead I'm getting np.float64 and np.int64

Answer 1

The default depends on your system. On a 64-bit system, default types will be 64-bit. On a 32-bit system, default types will be 32-bit. There is no way to change the default short of re-compiling numpy with a different system C header.

You can of course specify dtypes explicitly, e.g.

>>> x = np.array(1, dtype='int32')

Edit: as kazemakase mentions below, the above is only true for int32/int64. In recent numpy versions, the default for floating-point is float64 regardless of the system.