DPOFA - DPOFA factors a double precision symmetric positive definite
DPOFA is usually called by DPOCO, but it can be called directly with a
saving in time if RCOND is not needed. (time for DPOCO) = (1 +
18/N)*(time for DPOFA) .
A DOUBLE PRECISION(LDA, N)
the symmetric matrix to be factored. Only the
diagonal and upper triangle are used.
the leading dimension of the array A .
the order of the matrix A . On Return
A an upper triangular matrix R so that A = TRANS(R)*R
where TRANS(R) is the transpose.
The strict lower triangle is unaltered.
If INFO .NE. 0 , the factorization is not complete.
= 0 for normal return.
= K signals an error condition. The leading minor
of order K is not positive definite. LINPACK. This version dated
08/14/78 . Cleve Moler, University of New Mexico, Argonne National Lab.
Subroutines and Functions BLAS DDOT Fortran DSQRT
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