HP MLIB User's Guide Vol. 2 7th Ed.

Chapter 15 Sparse Eigenvalues and Eigenvectors 1045
Matrix structure input by column DSEVIC
Name DSEVIC
Matrix structure input by column
Purpose This subprogram adds a list of indices in a single column in the lower triangle
to the set of known nonzeros for one of the sparse matrices.
Usage VECLIB:
CHARACTER*1 matrix
INTEGER*4 jcol, nzcol, jrowin(nzcol), ier
REAL*8 global(150)
CALL DSEVIC(matrix, jcol, nzcol, jrowin, global, ier)
VECLIB8:
CHARACTER*1 matrix
INTEGER*8 jcol, nzcol, jrowin(nzcol), ier
REAL*8 global(150)
CALL DSEVIC(matrix, jcol, nzcol, jrowin, global, ier)
Input matrix Character string denoting the matrix for which the
nonzero location is being input:
’A’ or ’a’ or
’K’ or ’k’ Add nonzero to the matrix on the left
side.
’B’ or ’b’ or
’M’ or ’m’ Add nonzero to the matrix on the right
side.
jcol Column index, 1 ≤ jcol ≤ norder, where norder is the
matrix order as specified in the call to DSEVIN.
Columns must be presented in order from 1 to norder,
except that columns with no entries can be skipped.
nzcol Number of nonzeros in column jcol of the matrix,
nzcol ≥ 0.
jrowin List of row indices for all nonzeros, in ascending order,
in the lower triangle part of column jcol of the matrix
designated by matrix, jcol ≤jrowin(1) < jrowin(2) < ... <
jrowin(nzcol) ≤ norder.
Input of diagonal entries is optional.
Updated global Global communications array for this problem. This
array must be passed, untouched by the user, to
successive subroutines in this package.