fill_value handling has changed in numpy=2.4.0

[valeriupredoi]

Description

In numpy=2.4.0 a one-element np.ndarray missing_value is not accepted anymore once the fill_value is a float, and tosses a ValueError: setting an element with a sequence, and as of numpy/numpy#29421 and numpy/numpy#29423 it only accepts floats and strings. This comes from a now-enforced Deprecation that allows only 0-dim arrays to be converted to scalars:

TypeError: only 0-dimensional arrays can be converted to Python scalars

See numpy/numpy#30591

The MRE I posted at numpy:

import numpy as np


# works fine
missing_value = 33.
data = np.ma.array(
    [[[-900., 33.], [33., -900], [33., 44.]]],
    mask=False,
    fill_value=-900.0,
    dtype=float
)
s = np.ma.masked_equal(data, missing_value)
print(s)

# fails only with numpy=2.4.0
missing_value = np.array([33.], dtype=float)
data = np.ma.array(
    [[[-900., 33.], [33., -900], [33., 44.]]],
    mask=False,
    fill_value=-900.0,
    dtype=float
)
s = np.ma.masked_equal(data, missing_value)
print(s)

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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.04%. Comparing base (c8e7d8a) to head (531ff1c).
⚠️ Report is 6 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #303      +/-   ##
==========================================
+ Coverage   86.00%   86.04%   +0.04%     
==========================================
  Files           7        7              
  Lines         643      645       +2     
==========================================
+ Hits          553      555       +2     
  Misses         90       90              

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[davidhassell]

Hang on! Only just reviewing this now ....

The missing_value attribute int the file can be a vector of two or more numbers, so well need to deal with this case to allow for the possibility of multiple setting of data = np.ma.masked_equal(data, missing_value)

[valeriupredoi]

@davidhassell ah snap, sorry! Let me open a PR with that fix, I thought the missing value is always a single float