numpy / numpy/numpy

BUG: datetime64(np.int64(123), 'ns') fails but datetime64(123, 'ns') is ok

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00 - Bug
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Python
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Description

Describe the issue:

converting integers to np.datetime64 fails for numpy np.int64 integers.

np.datetime64(np.int64(123), 'ns')  # ValueError: Could not convert object to NumPy datetime
np.datetime64(123, 'ns')  # ok
Reproduce the code example:
np.datetime64(np.int64(123), 'ns')  # ValueError: Could not convert object to NumPy datetime
np.datetime64(123, 'ns')  # ok
Error message:
np.datetime64(np.int64(123), 'ns')
*** ValueError: Could not convert object to NumPy datetime
NumPy/Python version information:

1.23.2 3.8.10 (default, Jun 22 2022, 20:18:18)
[GCC 9.4.0]

Context for the issue:

No response

Contributor guide

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First steps

  1. Read the whole issue, then the project's contributing guide.
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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by reproducing the two np.datetime64 examples from the issue, using the reported NumPy and Python versions if available. Trace the conversion path for np.int64 values and compare it with native integers; done means np.datetime64(np.int64(123), 'ns') succeeds consistently without changing the native-integer behavior.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
data
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
45/100

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