source-academy / py-slang / 29675068251

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Committed by web-flow

Commit Message

fix: use Math.hypot for complex magnitude to avoid overflow (#286)

Computing a complex modulus as sqrt(re*re + im*im) overflows to
Infinity when a component's square leaves the float range, even
though the true modulus is representable (abs(complex(1e200, 0))
returned inf instead of 1e200). Math.hypot scales internally and is
what CPython itself uses for abs(complex).

Replace the sqrt-of-squares form at the three remaining sites — the
CSE machine's abs builtin, the PVML interpreter's abs, and
PyComplexNumber.pow's magnitude — aligning them with the stepper
engine (conductor/stepper), which already uses Math.hypot, and with
py2js since #282.

Add directed tests: abs(1e200+0j) through the shared CSE/Pynter/PVML
/CPython suites, and a PyComplexNumber.pow case whose intermediate
square overflows.

Fixes #284

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