Precision of Laurent series is restricted to be positive

[soehms]

The problem occured in context with #4618 (see comment 32) and is explained by the following code:

sage: L.<x> = LaurentSeriesRing(QQ)
sage: q = x^2 + x^3
sage: q.add_bigoh(-1)
Traceback (most recent call last):
...
ValueError: prec (= -3) must be non-negative

CC: @tscrim

Component: algebra

Keywords: Laurent series precision days100

Author: Sebastian Oehms

Branch/Commit: 14878d5

Reviewer: Travis Scrimshaw

Issue created by migration from https://trac.sagemath.org/ticket/28239

[embray]

comment:1

Ticket retargeted after milestone closed

[soehms]

Branch: u/soehms/neg_prec_laurent_series_28239

[soehms]

Author: Sebastian Oehms

[soehms]

Commit: 9a35541

[soehms]

comment:3

Just changed one line of code.

---

New commits:

9a35541

28239: initial version

[tscrim]

Reviewer: Travis Scrimshaw

[tscrim]

comment:4

Can we also add sage: (t^(-2)).add_bigoh(-2) and remove the full-stop/period at the end of the INPUT: line. Once done, you can set a positive review.

[sagetrac-git]

Changed commit from 9a35541 to 14878d5

[sagetrac-git]

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

14878d5

28239: fix according to review

[vbraun]

Changed branch from u/soehms/neg_prec_laurent_series_28239 to 14878d5