frat=
rat
Fill-in ratio over which some column block will not amalgamate one of
its descendents in the elimination tree. Typical values range from 0
.
05
to 0
.
10.
f
Block Halo Approximate Minimum Fill method. The parameters of the Halo
Approximate Minimum Fill method are listed below.
cmin=
size
Minimum number of columns per column block. All column blocks of
width smaller than
size
are amalgamated to their parent column block in
the elimination tree, provided that it does not violate the
cmax
constraint.
cmax=
size
Maximum number of column blocks over which some column block will
not amalgamate one of its descendents in the elimination tree. This
parameter is mainly designed to provide an upper bound for block size
in the context of BLAS3 computations ; else, a huge value should be
provided.
frat=
rat
Fill-in ratio over which some column block will not amalgamate one of
its descendents in the elimination tree. Typical values range from 0
.
05
to 0
.
10.
g
Gibbs-Poole-Stockmeyer method. This method is used on separators to reduce
the number and extent of extra-diagonal blocks. If the number of extra-
diagonal blocks is not relevant, the
s
method should be preferred. This method
has only one parameter.
pass=
nbr
Set the number of sweeps performed by the algorithm.
n
Nested dissection method. The parameters of the nested dissection method
are given below.
ole=
strat
Set the ordering strategy that is used on every leaf of the separators tree
if the node separation strategy
sep
has failed to separate it further.
ose=
strat
Set the ordering strategy that is used on every separator of the separators
tree.
sep=
strat
Set the node separation strategy that is used on every leaf of the sep-
arators tree to make it grow. Node separation strategies are described
below, in section 7.3.5.
s
Simple method. Vertices are ordered in their natural order. This method is
fast, and should be used to order separators if the number of extra-diagonal
blocks is not relevant ; else, the
g
method should be preferred.
v
Mesh-to-graph method. Available only for mesh ordering strategies. From the
mesh to which this method applies is derived a graph, such that a graph vertex
is associated with every node of the mesh, and a clique is created between all
vertices which represent nodes that belong to the same element. A graph
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