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SUBROUTINE SPOSL(A,LDA,N,B)
INTEGER LDA,N
REAL A(LDA,1),B(1)
C
C SPOSL SOLVES THE REAL SYMMETRIC POSITIVE DEFINITE SYSTEM
C A * X = B
C USING THE FACTORS COMPUTED BY SPOCO OR SPOFA.
C
C ON ENTRY
C
C A REAL(LDA, N)
C THE OUTPUT FROM SPOCO OR SPOFA.
C
C LDA INTEGER
C THE LEADING DIMENSION OF THE ARRAY A .
C
C N INTEGER
C THE ORDER OF THE MATRIX A .
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 WILL OCCUR IF THE INPUT FACTOR CONTAINS
C A ZERO ON THE DIAGONAL. TECHNICALLY THIS INDICATES
C SINGULARITY BUT IT IS USUALLY CAUSED BY IMPROPER SUBROUTINE
C ARGUMENTS. IT WILL NOT OCCUR IF THE SUBROUTINES ARE CALLED
C CORRECTLY AND INFO .EQ. 0 .
C
C TO COMPUTE INVERSE(A) * C WHERE C IS A MATRIX
C WITH P COLUMNS
C CALL SPOCO(A,LDA,N,RCOND,Z,INFO)
C IF (RCOND IS TOO SMALL .OR. INFO .NE. 0) GO TO ...
C DO 10 J = 1, P
C CALL SPOSL(A,LDA,N,C(1,J))
C 10 CONTINUE
C
C LINPACK. THIS VERSION DATED 08/14/78 .
C CLEVE MOLER, UNIVERSITY OF NEW MEXICO, ARGONNE NATIONAL LAB.
C
C SUBROUTINES AND FUNCTIONS
C
C BLAS SAXPY,SDOT
C