Accept several arguments in RealIntervalFieldElement.min and RealIntervalFieldElement.max

[cheuberg]

Python's min and max are not suitable for RealIntervalFieldElement, as those are not linearly ordered; the existing methods RealIntervalFieldElement.min and RealIntervalFieldElement.max
only compute the minimum or maximum of self and other.

This ticket rewrites the methods RealIntervalFieldElement.min and RealIntervalFieldElement.max to accept an arbitrary number of arguments.

CC: @sagetrac-skropf

Component: numerical

Keywords: RIF

Author: Clemens Heuberger

Branch/Commit: 27080b5

Reviewer: Daniel Krenn

Issue created by migration from https://trac.sagemath.org/ticket/17198

[cheuberg]

Branch: u/cheuberg/rings/RIF-min-max

[cheuberg]

New commits:

c8f8523

Trac #17198: New functions max_RIF and min_RIF

[cheuberg]

Commit: c8f8523

[jdemeyer]

comment:3

I think it would be more useful to have these as methods on RIF elements.

[cheuberg]

comment:4

My reasoning for having it as a function as opposed to methods on RIF elements where:

1. There are methods .min and .max performing the operation for the minimum and maximum of two elements
2. I think that the functions as proposed here are easier to use, e.g., the infinity norm of a vector of real intervals could simply be written as max_RIF(abs(r) for r in v).
   Therefore, I felt that having those as functions in the module real_mpfi (and not importing those in the global name space) is appropriate.

[sagetrac-git]

Changed commit from c8f8523 to 27080b5

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

27080b5

Trac #17198: Rewrote methods .min and .max to handle more than two elements

[cheuberg]

comment:6

Replying to @jdemeyer:

I think it would be more useful to have these as methods on RIF elements.

I now rewrote the original methods of RealIntervalField to achieve what I intended with the functions.

[dkrenn]

Reviewer: Daniel Krenn

[dkrenn]

comment:7

Looks good. Merges cleanly on 6.5.rc0. I'm still waiting for "make ptestlong" to finish...

[vbraun]

Changed branch from u/cheuberg/rings/RIF-min-max to 27080b5