Improper cast in rf neuron process

[Michaeljurado42]

Objective of issue: sin_decay, and cos decay need to be casted to np.int32 instead of int. (Else you can't instantiate an array of neurons).

Lava version:

• 0.6.0 (feature release)
• 0.5.1 (bug fixes)
• [] 0.5.0 (current version)
• 0.4.1
• 0.4.0
• 0.3.0
• 0.1.2

I'm submitting a ...

• bug report
• feature request
• documentation request

Current behavior:

• Rf neuron fails with array of periods passed into the neuron

Expected behavior:

• Rf neuron should be able to be instantiated with an array or list of periods.

Steps to reproduce:

1. Instantiate an rf neuron: neuron = RF(shape=(2,), period=np.array([10, 20]))
2. Run the graph: neuron.run(condition=RunSteps(num_steps=num_steps, blocking=True), run_cfg=run_config)

Related code:

rf/process.py looks like this:

...
        if decay_bits > 0:
            sin_decay = int(sin_decay * (1 << decay_bits))
            cos_decay = int(cos_decay * (1 << decay_bits))

when it should look like this:

...
        if decay_bits > 0:
            sin_decay = np.int32(sin_decay * (1 << decay_bits))
            cos_decay = np.int32(cos_decay * (1 << decay_bits))

Other information:

Traceback (most recent call last):
  File "C:\Users\mjurado3\workspace\lava_dev\lava\test_resonator_process.py", line 65, in <module>
    neuron = RF(shape=(n_neurons,), period=np.array([10, 20]), alpha=alpha,
  File "C:\Users\mjurado3\workspace\lava_dev\lava-dl\.venv\lib\site-packages\lava\magma\core\process\process.py", line 33, in __call__
    obj = type.__call__(cls, *args, **kwargs)
  File "C:\Users\mjurado3\workspace\lava_dev\lava-dl\.venv\lib\site-packages\lava\proc\rf\process.py", line 71, in __init__
    sin_decay = int(sin_decay * (1 << decay_bits))
TypeError: only size-1 arrays can be converted to Python scalars

Issue came up when I was writing rf neuron code for netx.