(3M) Calculator User Manual

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=s ize
Minimum number of columns per co lumn block. All column blocks of
width smaller than size are amalgamated to their parent c olumn block in
the elimination tree, provided that it does not violate the cmax c onstraint.
cmax=s ize
Maximum number of column blocks over which some column block will
not a malgamate one of its desce ndents in the eliminatio n tree. This
parameter is mainly designed to provide an upper bound for block s ize
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-Po ole-Stockmeyer method. This metho d 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 per formed by the algorithm.
n Nested dissection method. The parameters of the nes ted dissection method
are given below.
ole=st rat
Set the ordering strategy that is used on every leaf of the separators tree
if the node s eparation strategy sep has failed to separate it further.
ose=st rat
Set the ordering strategy that is used on every separator of the separators
tree.
sep=st rat
Set the node separation strategy that is used on every leaf of the sep-
arator s tree to make it g row. 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 s hould 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 gra ph vertex
is associated with every node of the mesh, and a clique is created between all
vertices which repre sent nodes that belong to the same element. A graph
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