Custom Query (733 matches)

Absolute factorization fails to factor x2 - t over QQ(t).

                     SINGULAR                                 /  Development
 A Computer Algebra System for Polynomial Computations       /   version 4.1.0
                                                           0<
 by: W. Decker, G.-M. Greuel, G. Pfister, H. Schoenemann     \   Nov 2016
FB Mathematik der Universitaet, D-67653 Kaiserslautern        \
// ** executing /scratch/hannes/snork/Singular/LIB/.singularrc
> LIB "absfact.lib";
// ** loaded /scratch/hannes/snork/Singular/LIB/absfact.lib (4.0.0.0,Jun_2013)
>  ring R = (0, t), (x), dp;
>  poly f = x^2 - t;
>  def S = absFactorize(f);

// 'absFactorize' created a ring, in which a list absolute_factors (the
// absolute factors) is stored.
// To access the list of absolute factors, type (if the name S was assigned
// to the return value):
//        setring(S); absolute_factors;
  
> setring(S);
> absolute_factors;
[1]:
   _[1]=1
   _[2]=x2+(-t)
[2]:
   1,1
[3]:
   _[1]=(a)
   _[2]=(a)
[4]:
   1

There seems to be no way to list the current working directory in Singular. Moreover, no way to change the working directory. This is a serious problem when using Singular in several different projects, each project of course having a folder devoted to files of only that project. And, the Singular is started from a desktop icon, there is no way to choose what working directory it has.

The CTRL-C prompt is really annoying for Sage (or potentially other software interfacing with Singular):

                     SINGULAR                                 /  Development
 A Computer Algebra System for Polynomial Computations       /   version 3-1-3
                                                           0<
 by: W. Decker, G.-M. Greuel, G. Pfister, H. Schoenemann     \   March 2011
FB Mathematik der Universitaet, D-67653 Kaiserslautern        \
> ^C// ** Interrupt at cmd:`$INVALID$` in line:';'
abort command(a), continue(c) or quit Singular(q) ?

The attached patch adds a command-line option --cntrlc=CHAR which skips the CTRL-C prompt and automatically answers CHAR. i.e. running Singular using

Singular --cntrlc=a

will always "abort" on CTRL-C.