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

Chapter 11 Introduction to Distributed SuperLU 783
Solve systems of linear equations pdgssvx/ pzgssvx, pdgssvx_ABglobal/pzgssvx_ABglobal
• etree (int*) Elimation tree of A'*A, dimension
A->ncol. It is computed in sp_colorder( ) during the
first factorizations of the matrices with the same
nonzero pattern. On exit of sp_colorder( ), the
columns of A are permuted so that the etree is in a
certain postorder. This postorder is reflected in
ScalePermstruct->perm_c.
NOTE etree is a vector of parent pointers for a forest whose vertices are the
integers 0 to A->ncol-1; etree[root]=A->ncol.
• Glu_persist (Glu_persist_t*) Global data structure
(xsup, supno) replicated on all processes, describing
the supernode partition in the factored matrices L
and U:
xsup[s] is the leading column of the s-th supernode.
supno[i] is the supernode number to which column i
belongs.
• Llu (LocalLU_t*) The distributed data structures to
store L and U factors.
SOLVEstruct
(input/output)
The data structure to hold the communication pattern
used in the phases of triangular solution an iterative
refinement. This pattern should be initialized only once
for repeated solutions. If options->SolveInitialized =
YES
, it is an input argument. If
options->SolveInitialized = NO and nrhs ! = 0, it is an
output argument.
berr
(output)
The vector with dimension nrhs containing the
componentwise relative backward error of each
solution vector X(j) (i.e., the smallest relative change in
any element of A or B that makes X(j) an exact
solution).
stat
(output)
Record the statistics on runtime and floating-point
operation count.