New Issue: [Documentation]: Add warning about exponentiation and 'real'/'imag'/'complex'

lydia-duncan-github · July 29, 2024, 3:35pm

25660, "lydia-duncan", "[Documentation]: Add warning about exponentiation and 'real'/'imag'/'complex'", "2024-07-29T15:34:17Z"

github.com/chapel-lang/chapel

[Documentation]: Add qualification about exponentiation and `real`/`imag`/`complex`

opened 03:34PM - 29 Jul 24 UTC

lydia-duncan

area: Docs user issue

### Summary of Problem **Description:** This was reported by Damian in [ou…r mailing list](https://chapel.discourse.group/t/exponential-operator-and-the-numerical-error-in-using-it/10020/11). He said there: > Some words of wisdom like the following need to be added to the > definition of the exponentiation operator (as well as the complex > and imag cases being documented): > > This operator is unlike other mathematical operators for floating > point data which are correctly rounded, i.e. have a rounding error > which is not greater than 0.5 * ULP (1). At best, exponentiation of > a floating point number achieves a rounding error which is for a > floating point exponent is guaranteed to not exceed 1 * ULP(1) > with an underlying robust mathematical library. For the optimized > cases of integral exponents of floating point data, the rounding > error in most cases does not exceed several ULPs, although that > is not guaranteed. > > A more succinct version of the above would be better which could > reference the above would be good.

Summary of Problem

Description:

This was reported by Damian in our mailing list. He said there:

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New Issue: [Documentation]: Add warning about exponentiation and 'real'/'imag'/'complex'

Summary of Problem

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