Fix array cast error, document

[jas88]

Proposed Changes

Trivial fix for array casting error

Types of changes

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• Bugfix (non-breaking change which fixes an issue)
• New Feature (non-breaking change which adds functionality)
• Breaking Change (fix or feature that would cause existing functionality to not work as expected)
• Documentation-Only Update (if none of the other choices apply)
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Checklist

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• Reviewed the contributing guidelines for this repository
• Ensured that the PR branch is in sync with the target branch (i.e. it is automatically merge-able)
• Updated any relevant API documentation
• Created or updated any tests if relevant
• Accurately updated the CHANGELOG
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Issues

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• Closes #<issue-number>
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