[GAP Forum] Issue with ALNUTH

[Dima Pasechnik]

Dear Kashyap,
On Sun, Mar 29, 2015 at 11:53:15AM +0530, Dr. Kashyap Rajeevsarathy wrote:
> Dear Forum,
> 
> There seems to be some problem factoring rational polynomials using ALNUTH.
> Please glance through the following examples and let me know if I am doing
> something wrong, of if there is a problem with the package installation:

Do you have PARI/GP installed on your machine?
(this probably will be not easy, if at all possible, on a Windows
machine, but easy to install on Linux or OSX)

PARI/GP is an external dependency for this package, 
as you can see from its installation instructions.

Best,
Dmitrii

> 

> 
> 
> 
> 
> 
> 
> 
> *1) gap> x := Indeterminate(Rationals,"x");;gap> pol := x^2-3;x^2-3gap> L
> := FieldByPolynomial(x^2-3);<algebraic extension over the Rationals of
> degree 2>gap> y := Indeterminate( L, "y" );;gap>
> FactorsPolynomialAlgExt(L,pol);*
> 
> 
> 
> 
> 
> 
> 
> *Error, AL_EXECUTABLE, the executable for PARI/GP, has to be set called
> fromProcessPariGP( Concatenation( input ), "polyfactors.gp
> <http://polyfactors.gp>" ) called fromPolynomialFactorsDescriptionPari( H,
> coeffs ) called fromFactorsPolynomialPari( AlgExtEmbeddedPol( H, poly ) )
> called from<function "FactorsPolynomialAlgExt">( <arguments> )called from
> read-eval loop at line 5 of *stdin*you can 'quit;' to quit to outer loop,
> oryou can 'return;' to continue*
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> *2) gap> SplittingField(pol);<algebraic extension over the Rationals of
> degree 2>gap> x := Indeterminate(Rationals,"x");       xgap> pol := x^2 -
> 3;x^2-3gap> L := SplittingField(pol);<algebraic extension over the
> Rationals of degree 2>gap> FactorsPolynomialAlgExt(L,pol);Error,
> AL_EXECUTABLE, the executable for PARI/GP, has to be set called from
> ProcessPariGP( Concatenation( input ), "polyfactors.gp
> <http://polyfactors.gp>" ) called fromPolynomialFactorsDescriptionPari( H,
> coeffs ) called fromFactorsPolynomialPari( AlgExtEmbeddedPol( H, poly ) )
> called from<function "FactorsPolynomialAlgExt">( <arguments> )called from
> read-eval loop at line 9 of *stdin*you can 'quit;' to quit to outer loop,
> oryou can 'return;' to continue*
> 
> Sincerely,
> Kashyap
> -- 
> Kashyap Rajeevsarathy
> Assistant Professor,
> Indian Institute of Science Education and Research (IISER) Bhopal,
> Indore By-pass Road,
> Bhauri, Bhopal - 462066,
> Madhya Pradesh, India.
> Phone: +91-755-669-2364
> Website: https://home.iiserb.ac.in/~kashyap
> _______________________________________________
> Forum mailing list
> Forum at mail.gap-system.org
> http://mail.gap-system.org/mailman/listinfo/forum