Re: question on collecting t_MAT

[hermann@stamm-wilbrandt.de]

On 2026-05-22 14:58, Bill Allombert wrote:
> Maybe I should allow
> ? [type(A)|e<-[1,2];A=matrix(2,2,x,y,e)]
>
> Cheers,
> Bill
If it is not only for type, that what be wonderful.

The first 9 assignments below have to be <-[...] because of selection 
from list.
But if "A=[a11,a12,a13;a21,a22,a23;a31,a32,a33]" would work
instead of workaround below that would increase readability:

  Ms=[A|a11<-S;a12<-S;a13<-S;
        a21<-S;a22<-S;a23<-S;
        a31<-S;a32<-S;a33<-S;
        A<-[[a11,a12,a13;a21,a22,a23;a31,a32,a33]],
        matdet(A)^2==1 && no0(A^-1)
     ];

But allow that only if you do not have to change the compiler too much
(I worked as Compiler Level3 support engineer at IBM the last 18 years 
before early retirement last year).

Regards,

Hermann.

P.S:
Another "issue" I found is that with "A=matrix(3,3);" before above 
command
"A[1,1]<-S" instead of "a11<-S" errors out:

  ***   variable name expected: 
Ms=[A|A[1,1]<-S;a12<-S;a13<-S;a21<-S;a22<-S;a2
  ***                                 
^----------------------------------------


This would be even better readable if it would work:

{
  A=matrix(3,3);
  Ms=[A|A[1,1]<-S;A[1,2]<-S;A[1,3]<-S;
        A[2,1]<-S;A[2,2]<-S;A[2,3]<-S;
        A[3,1]<-S;A[3,2]<-S;A[3,3]<-S,
        matdet(A)^2==1
     ];
}