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SUBROUTINE SSPSL(AP,N,KPVT,B) INTEGER N,KPVT(1) REAL AP(1),B(1) C C SSISL SOLVES THE REAL SYMMETRIC SYSTEM C A * X = B C USING THE FACTORS COMPUTED BY SSPFA. C C ON ENTRY C C AP REAL(N*(N+1)/2) C THE OUTPUT FROM SSPFA. C C N INTEGER C THE ORDER OF THE MATRIX A . C C KPVT INTEGER(N) C THE PIVOT VECTOR FROM SSPFA. C C B REAL(N) C THE RIGHT HAND SIDE VECTOR. C C ON RETURN C C B THE SOLUTION VECTOR X . C C ERROR CONDITION C C A DIVISION BY ZERO MAY OCCUR IF SSPCO HAS SET RCOND .EQ. 0 C OR SSPFA HAS SET INFO .NE. 0 . C C TO COMPUTE INVERSE(A) * C WHERE C IS A MATRIX C WITH P COLUMNS C CALL SSPFA(AP,N,KPVT,INFO) C IF (INFO .NE. 0) GO TO ... C DO 10 J = 1, P C CALL SSPSL(AP,N,KPVT,C(1,J)) C 10 CONTINUE C C LINPACK. THIS VERSION DATED 08/14/78 . C JAMES BUNCH, UNIV. CALIF. SAN DIEGO, ARGONNE NAT. LAB. C C SUBROUTINES AND FUNCTIONS C C BLAS SAXPY,SDOT C FORTRAN IABS C