ASKSAGE: Sage Q&A Forum - RSS feedhttps://ask.sagemath.org/questions/Q&A Forum for SageenCopyright Sage, 2010. Some rights reserved under creative commons license.Sat, 19 Mar 2022 14:55:13 +0100Recognize a power series in two variables as a rational functionhttps://ask.sagemath.org/question/61507/recognize-a-power-series-in-two-variables-as-a-rational-function/ Hi!
I can get Sage to calculate a power series in two variables to any desired precision. I expect that the power series is in fact the ratio of two low-degree polynomials. Is there a way to get Sage to guess what rational function it is? Thanks for your help!Tue, 15 Mar 2022 03:16:44 +0100https://ask.sagemath.org/question/61507/recognize-a-power-series-in-two-variables-as-a-rational-function/Comment by slelievre for <p>Hi!</p>
<p>I can get Sage to calculate a power series in two variables to any desired precision. I expect that the power series is in fact the ratio of two low-degree polynomials. Is there a way to get Sage to guess what rational function it is? Thanks for your help!</p>
https://ask.sagemath.org/question/61507/recognize-a-power-series-in-two-variables-as-a-rational-function/?comment=61553#post-id-61553Any chance to provide a toy example here?Sat, 19 Mar 2022 14:55:13 +0100https://ask.sagemath.org/question/61507/recognize-a-power-series-in-two-variables-as-a-rational-function/?comment=61553#post-id-61553Comment by HughThomas for <p>Hi!</p>
<p>I can get Sage to calculate a power series in two variables to any desired precision. I expect that the power series is in fact the ratio of two low-degree polynomials. Is there a way to get Sage to guess what rational function it is? Thanks for your help!</p>
https://ask.sagemath.org/question/61507/recognize-a-power-series-in-two-variables-as-a-rational-function/?comment=61535#post-id-61535This looks great! However, it seems like it only handles power series in a single variable, so I think it doesn't actually solve my problem.
Edited to add: once I set the two variables equal, so as to get a power series in one variable, I was able to recognize the power series by the traditional approach, i.e., looking the series of coefficients up in OEIS. (And then I was able to guess how to put the two variables back in.) So my specific problem is solved. Thanks for the help!Thu, 17 Mar 2022 02:59:55 +0100https://ask.sagemath.org/question/61507/recognize-a-power-series-in-two-variables-as-a-rational-function/?comment=61535#post-id-61535Comment by slelievre for <p>Hi!</p>
<p>I can get Sage to calculate a power series in two variables to any desired precision. I expect that the power series is in fact the ratio of two low-degree polynomials. Is there a way to get Sage to guess what rational function it is? Thanks for your help!</p>
https://ask.sagemath.org/question/61507/recognize-a-power-series-in-two-variables-as-a-rational-function/?comment=61511#post-id-61511You could look into the `ore_algebra` package:
- [https://github.com/mkauers/ore_algebra/](https://github.com/mkauers/ore_algebra/)Tue, 15 Mar 2022 11:23:37 +0100https://ask.sagemath.org/question/61507/recognize-a-power-series-in-two-variables-as-a-rational-function/?comment=61511#post-id-61511Comment by slelievre for <p>Hi!</p>
<p>I can get Sage to calculate a power series in two variables to any desired precision. I expect that the power series is in fact the ratio of two low-degree polynomials. Is there a way to get Sage to guess what rational function it is? Thanks for your help!</p>
https://ask.sagemath.org/question/61507/recognize-a-power-series-in-two-variables-as-a-rational-function/?comment=61510#post-id-61510Welcome to Ask Sage! Thank you for your question.Tue, 15 Mar 2022 11:22:29 +0100https://ask.sagemath.org/question/61507/recognize-a-power-series-in-two-variables-as-a-rational-function/?comment=61510#post-id-61510