ASKSAGE: Sage Q&A Forum - Individual question feedhttps://ask.sagemath.org/questions/Q&A Forum for SageenCopyright Sage, 2010. Some rights reserved under creative commons license.Wed, 10 Aug 2016 03:13:39 -0500Unhandled SIGABRT when working with polynomial ringshttps://ask.sagemath.org/question/34378/unhandled-sigabrt-when-working-with-polynomial-rings/Hello, experts!
I am working with multivariate polynomial rings in a finite field, such as
K.<a1,b1,a2,b2,x>=PolynomialRing(GF(32003))
But when I try to define an object like this one:
c1=numerator((a1+b1*I)+(a1-b1*I)*x^(-5))
I get a SIGABRT from Sage and the program terminates giving an Ubuntu error (something like "gdb stopped working").
This pastebin shows the output: http://pastebin.com/jKEM87aS. Even though it says `Saved trace to /home/slenderman/.sage/crash_logs/crash_oImBtz.log`, that file is totally empty.
**More information**: if I use the ring over Q it works perfectly
K.<a1,b1,a2,b2,x>=QQ[]
Also, I have Sage version 7.2 compiled from the git repository.
Thank you in advanced for any help!Tue, 09 Aug 2016 03:09:38 -0500https://ask.sagemath.org/question/34378/unhandled-sigabrt-when-working-with-polynomial-rings/Comment by osr for <p>Hello, experts! </p>
<p>I am working with multivariate polynomial rings in a finite field, such as</p>
<pre><code>K.<a1,b1,a2,b2,x>=PolynomialRing(GF(32003))
</code></pre>
<p>But when I try to define an object like this one:</p>
<pre><code>c1=numerator((a1+b1*I)+(a1-b1*I)*x^(-5))
</code></pre>
<p>I get a SIGABRT from Sage and the program terminates giving an Ubuntu error (something like "gdb stopped working").</p>
<p>This pastebin shows the output: <a href="http://pastebin.com/jKEM87aS">http://pastebin.com/jKEM87aS</a>. Even though it says <code>Saved trace to /home/slenderman/.sage/crash_logs/crash_oImBtz.log</code>, that file is totally empty.</p>
<p><strong>More information</strong>: if I use the ring over Q it works perfectly</p>
<pre><code>K.<a1,b1,a2,b2,x>=QQ[]
</code></pre>
<p>Also, I have Sage version 7.2 compiled from the git repository.</p>
<p>Thank you in advanced for any help!</p>
https://ask.sagemath.org/question/34378/unhandled-sigabrt-when-working-with-polynomial-rings/?comment=34380#post-id-34380@FrédéricC You are right, but even if I declare the ring with I as a variable `K.<a1,b1,a2,b2,x,I>=PolynomialRing(GF(32003))` I get the same SIGABRT error.Tue, 09 Aug 2016 04:19:14 -0500https://ask.sagemath.org/question/34378/unhandled-sigabrt-when-working-with-polynomial-rings/?comment=34380#post-id-34380Comment by FrédéricC for <p>Hello, experts! </p>
<p>I am working with multivariate polynomial rings in a finite field, such as</p>
<pre><code>K.<a1,b1,a2,b2,x>=PolynomialRing(GF(32003))
</code></pre>
<p>But when I try to define an object like this one:</p>
<pre><code>c1=numerator((a1+b1*I)+(a1-b1*I)*x^(-5))
</code></pre>
<p>I get a SIGABRT from Sage and the program terminates giving an Ubuntu error (something like "gdb stopped working").</p>
<p>This pastebin shows the output: <a href="http://pastebin.com/jKEM87aS">http://pastebin.com/jKEM87aS</a>. Even though it says <code>Saved trace to /home/slenderman/.sage/crash_logs/crash_oImBtz.log</code>, that file is totally empty.</p>
<p><strong>More information</strong>: if I use the ring over Q it works perfectly</p>
<pre><code>K.<a1,b1,a2,b2,x>=QQ[]
</code></pre>
<p>Also, I have Sage version 7.2 compiled from the git repository.</p>
<p>Thank you in advanced for any help!</p>
https://ask.sagemath.org/question/34378/unhandled-sigabrt-when-working-with-polynomial-rings/?comment=34379#post-id-34379What is I ? You should rather not use symbolic variables in polynomials. Otherwise, everything becomes symbolic, hence slow and better avoided.Tue, 09 Aug 2016 04:11:08 -0500https://ask.sagemath.org/question/34378/unhandled-sigabrt-when-working-with-polynomial-rings/?comment=34379#post-id-34379Answer by tmonteil for <p>Hello, experts! </p>
<p>I am working with multivariate polynomial rings in a finite field, such as</p>
<pre><code>K.<a1,b1,a2,b2,x>=PolynomialRing(GF(32003))
</code></pre>
<p>But when I try to define an object like this one:</p>
<pre><code>c1=numerator((a1+b1*I)+(a1-b1*I)*x^(-5))
</code></pre>
<p>I get a SIGABRT from Sage and the program terminates giving an Ubuntu error (something like "gdb stopped working").</p>
<p>This pastebin shows the output: <a href="http://pastebin.com/jKEM87aS">http://pastebin.com/jKEM87aS</a>. Even though it says <code>Saved trace to /home/slenderman/.sage/crash_logs/crash_oImBtz.log</code>, that file is totally empty.</p>
<p><strong>More information</strong>: if I use the ring over Q it works perfectly</p>
<pre><code>K.<a1,b1,a2,b2,x>=QQ[]
</code></pre>
<p>Also, I have Sage version 7.2 compiled from the git repository.</p>
<p>Thank you in advanced for any help!</p>
https://ask.sagemath.org/question/34378/unhandled-sigabrt-when-working-with-polynomial-rings/?answer=34384#post-id-34384I cannot reproduce your error, the error I get is :
PariError: I already exists with incompatible valence
which is fine. Indeed, the product of a polynomial indeterminate defined over a finite field and `I` (which belongs to a field of characteristic 0) is not well defined. If `I` is defined as another indeterminate, everything is fine:
sage: K.<a1,b1,a2,b2,x,I>=PolynomialRing(GF(32003))
sage: numerator((a1+b1*I)+(a1-b1*I)*x^(-5))
b1*x^5*I + a1*x^5 - b1*I + a1
In your case, the error is more annoying since it is not handled by Sage, and as the log says "his probably occurred because a *compiled* module has a bug in it and is not properly wrapped with sig_on(), sig_off(). Python will now terminate."
When you compiled Sage, and especially Pari, did you get any error ? Coud you look at the file `$SAGE_ROOT/logs/pkgs/pari-2.8-*.log` to see if something wrong happened there ?
If you do not find anything, could you try, from the `$SAGE_ROOT` direcory:
./sage -i -f -c pari
To rebuild pari and run a self-check ?
Tue, 09 Aug 2016 09:17:56 -0500https://ask.sagemath.org/question/34378/unhandled-sigabrt-when-working-with-polynomial-rings/?answer=34384#post-id-34384Comment by osr for <p>I cannot reproduce your error, the error I get is :</p>
<pre><code>PariError: I already exists with incompatible valence
</code></pre>
<p>which is fine. Indeed, the product of a polynomial indeterminate defined over a finite field and <code>I</code> (which belongs to a field of characteristic 0) is not well defined. If <code>I</code> is defined as another indeterminate, everything is fine:</p>
<pre><code>sage: K.<a1,b1,a2,b2,x,I>=PolynomialRing(GF(32003))
sage: numerator((a1+b1*I)+(a1-b1*I)*x^(-5))
b1*x^5*I + a1*x^5 - b1*I + a1
</code></pre>
<p>In your case, the error is more annoying since it is not handled by Sage, and as the log says "his probably occurred because a <em>compiled</em> module has a bug in it and is not properly wrapped with sig_on(), sig_off(). Python will now terminate."</p>
<p>When you compiled Sage, and especially Pari, did you get any error ? Coud you look at the file <code>$SAGE_ROOT/logs/pkgs/pari-2.8-*.log</code> to see if something wrong happened there ?</p>
<p>If you do not find anything, could you try, from the <code>$SAGE_ROOT</code> direcory:</p>
<pre><code> ./sage -i -f -c pari
</code></pre>
<p>To rebuild pari and run a self-check ?</p>
https://ask.sagemath.org/question/34378/unhandled-sigabrt-when-working-with-polynomial-rings/?comment=34401#post-id-34401The Pari build log didn't have any errors in it, but your suggestion of rebuilding Sage and running a self check worked like a charm, thank you!Wed, 10 Aug 2016 03:13:39 -0500https://ask.sagemath.org/question/34378/unhandled-sigabrt-when-working-with-polynomial-rings/?comment=34401#post-id-34401