4a8cbac06e
You can preview this rule [here](https://sonarsource.github.io/rspec/#/rspec/S6725/python) (updated a few minutes after each push). ## Review A dedicated reviewer checked the rule description successfully for: - [ ] logical errors and incorrect information - [ ] information gaps and missing content - [ ] text style and tone - [ ] PR summary and labels follow [the guidelines](https://github.com/SonarSource/rspec/#to-modify-an-existing-rule) Co-authored-by: maksim-grebeniuk-sonarsource <maksim-grebeniuk-sonarsource@users.noreply.github.com> Co-authored-by: Maksim Grebeniuk <maksim.grebeniuk@sonarsource.com>
60 lines
1.4 KiB
Plaintext
60 lines
1.4 KiB
Plaintext
This rule raises an issue when an equality check is made against ``++numpy.nan++``.
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== Why is this an issue?
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The ``++numpy.nan++`` is a floating point representation of Not a Number (NaN) used as a placeholder for undefined or missing values in numerical computations.
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Equality checks of variables against ``++numpy.nan++`` in NumPy will always be ``++False++`` due to the special nature of ``++numpy.nan++``. This can lead to unexpected and incorrect results.
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Instead of standard comparison the ``++numpy.isnan()++`` function should be used.
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=== Code examples
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==== Noncompliant code example
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[source,python,diff-id=1,diff-type=noncompliant]
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----
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import numpy as np
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x = np.nan
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if x == np.nan: # Noncompliant: always False
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...
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----
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==== Compliant solution
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[source,python,diff-id=1,diff-type=compliant]
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----
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import numpy as np
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x = np.nan
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if np.isnan(x):
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...
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----
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== Resources
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=== Documentation
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* NumPy API Reference - https://numpy.org/doc/stable/reference/constants.html#numpy.nan[numpy.nan]
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* NumPy API Reference - https://numpy.org/doc/stable/reference/generated/numpy.isnan.html[numpy.isnan()]
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ifdef::env-github,rspecator-view[]
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'''
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== Implementation Specification
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(visible only on this page)
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=== Message
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Use 'numpy.isnan()' function instead of direct comparison.
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'''
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== Comments And Links
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(visible only on this page)
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endif::env-github,rspecator-view[]
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