DPPDI(3F)

NAME
     DPPDI   - DPPDI computes the determinant and inverse of a double
     precision symmetric positive definite matrix using the factors computed
     by DPPCO or DPPFA .


SYNOPSYS
      SUBROUTINE DPPDI(AP,N,DET,JOB)

DESCRIPTION
     On Entry

     AP DOUBLE PRECISION (N*(N+1)/2)
        the output from DPPCO or DPPFA.

     N INTEGER
        the order of the matrix  A .

     JOB INTEGER
        = 11   both determinant and inverse.
        = 01   inverse only.
        = 10   determinant only.  On Return

     AP the upper triangular half of the inverse .
        The strict lower triangle is unaltered.

     DET DOUBLE PRECISION(2)
        determinant of original matrix if requested.
        Otherwise not referenced.
        DETERMINANT = DET(1) * 10.0**DET(2)
        with  1.0 .LE. DET(1) .LT. 10.0
        or  DET(1) .EQ. 0.0 .  Error Condition

     A division by zero will occur if the input factor contains a zero on the
     diagonal and the inverse is requested.  It will not occur if the
     subroutines are called correctly and if DPOCO or DPOFA has set INFO .EQ.
     0 .  LINPACK.  This version dated 08/14/78 .  Cleve Moler, University of
     New Mexico, Argonne National Lab.  Subroutines and Functions BLAS
     DAXPY,DSCAL Fortran MOD