Support RETURN-FROM in DEF%TR forms
[maxima.git] / share / hompack / fortran / qimuds.f
blob63365a104dbe67fd9d100f281e3417e9ff9ad641
1 SUBROUTINE QIMUDS(Q,F,MAXA,NN,LENAA)
3 C computes f := [Q**(-1)] * f .
5 C on input:
7 C Q is the preconditioning matrix, and contains an approximate
8 C factorization of M.
10 C f is the right hand side vector, Q z = f .
12 C MAXA, NN, LENAA describe Q in packed skyline storage format.
14 C on output:
16 C Q, MAXA, NN, LENAA are unchanged.
18 C f contains the solution z of Q z = f .
21 C Calls SOLVDS .
23 INTEGER LENAA,LENQ,NN,MAXA(NN+2),NQ
24 DOUBLE PRECISION Q(LENAA+NN+1),F(NN+1)
26 NQ=NN+1
27 LENQ=MAXA(NN+2)-1
29 CALL SOLVDS(NQ,Q,LENQ,MAXA,F)
31 RETURN
32 END