1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
|
function [f,sexp]=trianfml(f,sexp)
// [f [,sexp]]=trianfml(f [,sexp]) Triangularization of the symbolic matrix
// f ; Triangularization is performed by elementary row operations;
// sexp is a set of common expressions stored by the algorithm.
//!
//
// Copyright INRIA
[lhs,rhs]=argn(0)
[mf,nf]=size(f)
f_tra=f
//
// row loop
// ------------------------------
//
for nli=1:mf
//
[mf_tra,nf_tra]=size(f_tra)
//recherche du pivot dans la premiere colonne
c1=f_tra(:,1);
lc=length(c1);[lc,klc]=sort(lc);
pivot='0';l=mf_tra+1;
while (pivot=='0'&l>1),
l=l-1;
if c1(klc(l))<>'0' then pivot=c1(klc(l)),end,
end
if pivot<>'0' then
l=klc(l)
//
if l<>1 then f_tra([1 l],:)=f_tra([l 1],:);c1([1 l])=c1([l 1]);end
//
for k=2:mf_tra,
if c1(k)<>'0' then
f_tra(k,:)=cmb_lin(pivot,f_tra(k,:),c1(k),f_tra(1,:))
f_tra(k,1)='0'
if rhs==2 then
ns=prod(size(sexp)),
for kl=2:nf_tra
if length(f_tra(k,kl))>20 then
ns=ns+1
sexp(ns)=f_tra(k,kl)
f_tra(k,kl)='%('+string(ns)+')'
end;
end;
end;
end;
end;
f(mf-mf_tra+1:mf,nf-nf_tra+1:nf)=f_tra
f_tra=f_tra(2:mf_tra,2:nf_tra)
end
end;
endfunction
|
