#17777: unsigned infinity cannot be coerced into SR
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Reporter: rws | Owner:
Type: defect | Status: needs_review
Priority: major | Milestone: sage-6.6
Component: symbolics | Resolution:
Keywords: | Merged in:
Authors: Ralf Stephan | Reviewers:
Report Upstream: N/A | Work issues:
Branch: | Commit:
u/rws/unsigned_infinity_cannot_be_coerced_into_sr|
5609e513405ba231b522ff68d8f88fe9cf0caeff
Dependencies: | Stopgaps:
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Comment (by mmezzarobba):
The docstring of `sage.rings.infinity` states that:
The rules for arithmetic are that the unsigned infinity ring does not
canonically coerce to any other ring, and all other rings canonically
coerce to the unsigned infinity ring, sending all elements to the single
element "a number less than infinity" of the unsigned infinity ring.
Arithmetic and comparisons then take place in the unsigned infinity ring,
where all arithmetic operations that are well-defined are defined.
[...]
Any ordered ring coerces to the infinity ring in the obvious way.
So if I understand correctly `SR` already didn't respect this
specification. But this makes me wonder if your patch won't make
comparisons with infinities even more inconsistent. If you understand the
issues at hand better than I do, can you explain how this is all supposed
to work?
--
Ticket URL: <http://trac.sagemath.org/ticket/17777#comment:6>
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