Fix HTML table display on Numpy 2

[titodalcanton]

HTML tables in result web pages are broken with Numpy 2. This should fix it.

Standard information about the request

This is a bug fix.

This bug involves anything that makes HTML tables of data (this includes at least the all-sky offline search and PyGRB) but the fix not impact anything.

Motivation

The problem is described in #4968, but to summarize, HTML tables show up empty under Numpy 2 because the data array in JavaScript ends up being filled with strings like 'np.float64(7.1)' instead of proper numbers like 7.1.

Contents

I added an explicit conversion of Numpy's float and integer types to Python native floats and ints respectively, before they are passed to the template that renders them into JavaScript values.

Links to any issues or associated PRs

Fixes #4968.

Testing performed

I used the following code:

import numpy as np
from pycbc.results import html_table

th = ['int', 'float', 'string', 'uint32', 'float32', 'complex128']
td = [
    np.array([1, 2, 3, 4]),
    np.array([1.1, 2.2, 3.3, 4.4]),
    np.array(['a', 'b', 'c', 'xyz']),
    np.array([1, 2, 3, 4], dtype=np.uint32),
    np.array([1.1, 2.2, 3.3, 4.4], dtype=np.float32),
    np.array([10+1j, 20+2j, 30+3j, 40+4j], dtype=np.complex128)
]
ht = html_table(td, th, page_size=20)
file_name = f'table_numpy_{np.__version__}.html'
with open(file_name, 'w') as tf:
    tf.write(ht)

Before this fix, this produces HTML files that actually show up blank with both Numpy 1.23.5 and 2.1.2, i.e. this test uncovered an additional bug with complex arrays breaking the tables (admittely not a likely use case though):

http://leela.fisica.indivia.net/~tito/pycbc/test_html_tables_numpy_2/table_before_fix_numpy_1.23.5.html

http://leela.fisica.indivia.net/~tito/pycbc/test_html_tables_numpy_2/table_before_fix_numpy_2.1.2.html

After this fix, I get identical-looking tables with both Numpy versions:

http://leela.fisica.indivia.net/~tito/pycbc/test_html_tables_numpy_2/table_after_fix_numpy_1.23.5.html

http://leela.fisica.indivia.net/~tito/pycbc/test_html_tables_numpy_2/table_after_fix_numpy_2.1.2.html

Additional notes

N/A

• The author of this pull request confirms they will adhere to the code of conduct

[spxiwh]

Thanks, approved assuming it works, one minor optional comment/thought.

[spxiwh]

Is there a reason not to just convert everything to string and avoid the type checks here?

[titodalcanton]

If we convert floats and ints to string, they will show up in the JavaScript as '12.3' instead of 12.3, and we will be back to the same problem, i.e. JavaScript will see an array of strings instead of numbers.