Support uint32_t input data

[graeme-winter]

Could clobber it down to 16 bits for the calculation but a lot of example data are recorded with an exposure time with an Eiger which allows 32 bit readout. In the cases I looked at the data would fit into 16 bits so this is mostly a data wrangling question.

Alt: have an implementation which will correctly handle uint32_t input data i.e. using more bits for the accumulators (particularly ∑i^2)

[graeme-winter]

In absence of that, the following script can also be used to truncate example data

import os
import sys

import h5py
import hdf5plugin
import numpy
import tqdm

def truncate(fin, fout):
    assert os.path.exists(fin)
    assert not os.path.exists(fout)

    with h5py.File(fin, "r") as i, h5py.File(fout, "w") as o:
        d = i["data"]
        e = o.create_dataset(
            "data",
            shape=d.shape,
            chunks=d.chunks,
            dtype=numpy.uint16,
            **hdf5plugin.Bitshuffle(),
        )

        # copy attributes
        for k, v in d.attrs.items():
            e.attrs[k] = v

        # copy data
        for j in tqdm.tqdm(range(d.shape[0])):
            e[j, :, :] = d[j, :, :]

if __name__ == "__main__":
    truncate(*sys.argv[1:])

N.B. this does not address subtlety around trusted ranges