`np.char.chararray` constructor deprecated in numpy >= 2.5.0

[xyf5432]

Affected File

python/Graphs/multi_heuristic_astar.py:82

Current Code

def do_something(back_pointer, goal, start):
    grid = np.char.chararray((n, n))
    for i in range(n):
        for j in range(n):
            grid[i][j] = "*"
    ...

Root Cause

numpy.char.chararray was deprecated in numpy 2.5.0 (numpy/numpy#30605). Constructing a chararray via np.char.chararray((n, n)) now emits:

DeprecationWarning: The chararray class is deprecated

The constructor is called each time do_something runs, which means the warning fires repeatedly during the search algorithm's execution.

Impact

• Severity: Medium — every call to do_something produces a DeprecationWarning on stderr, accumulating noise as the pathfinding algorithm iterates

Solution

Use a regular numpy array with a string dtype instead:

# Before:
grid = np.char.chararray((n, n))

# After:
grid = np.full((n, n), "*", dtype="<U1")

References

• numpy/numpy#30605 — DEP: deprecate chararray

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Thank you for taking a look! We would appreciate a confirmation on whether this is a real compatibility issue. Hope it's worth fixing in a future release.