Variable substitution within n matrices

[Nicola Bressanin]

I needed a program to read a few 3x3 matrices containing
variables,like N and T.
N and T are stored in the same directory; when invoking the program
(SOST) the newer N and T are present on stack levels 1 and 2.I solved
it with ->NUM in this program,but was there another(better) way to do
it?is SUBST helpful?

SOST
<<
'T' STO
'N' STO
Rr1 Rr2 Rr3 Rr4
->NUM 'Rr4S' STO
->NUM 'Rr3S' STO
->NUM 'Rr2S' STO
->NUM 'Rr1S' STO
Rr1S Rr2S Rr3S Rr4S
>>

[Han]

On Jan 11, 7:58 am, Nicola Bressanin <nicola.bressa...@gmail.com>
wrote:

From the listing you posted, it appears that Rr1, Rr2, Rr3, and Rr4
are static. Suppose that Rr1 looks like:

[ [ 1 2 N ] [ 4 5 T ] [ 7 8 9 ] ]

You could use:

<<
-> T N
<<
[ [ 1 2 N ] [ 4 5 T ] [ 7 8 9 ] ]
... insert the other 3 matrices here ...

>>
>>

This treats T and N as local variables. It takes T and N from the
stack, and then leaves four matrices with the T and N values
substituted into the matrices themselves for you to do whatever you
wish with them. This reduces the number of variables you have to keep
around in your directory.

[Nemo]

Hi, something like :

SOST : « -> T N L « L 1 « ->NUM ->NUM » DOLIST » »

Example :

1 2 { Rr1 Rr2 Rr3 Rr4 } SOST

Eventually Followed by { Rr1S Rr2S Rr3S Rr4S } STO

Of course you can put the list in the SOST prog if it is always the
same matrices

Gilles

[Nemo]

Another way is to use the | function. You can try this to
understand :


Rr1 « {'N' 3 'T' 5 } | » MAP

| do substitutions in an algebraic object and MAP apply a program on
each element of a matrice.In this case, N become 3 and T become 5

| is very interessing, for example you can do such things : Rr1 « {'N'
'N+1' 'T' '2*T' } | » MAP

[Nicola Bressanin]

Thanks i'll try it