| CHMfactor-class {Matrix} | R Documentation |
The virtual class "CHMfactor" is a class of
CHOLMOD-based Cholesky factorizations of symmetric, sparse,
compressed, column-oriented matrices. Such a factorization is
simplicial (virtual class "CHMsimpl") or supernodal (virtual
class "CHMsuper"). Objects that inherit from these classes are
either numeric factorizations (classes "dCHMsimpl" and
"dCHMsuper") or symbolic factorizations (classes
"nCHMsimpl" and "nCHMsuper").
Objects can be created by calls of the form new("dCHMsuper", ...)
but are more commonly created via Cholesky().
applied to dsCMatrix or
lsCMatrix objects.
of "CHMfactor" and all classes inheriting from it:
perm:colcount:"integer" .... type:"integer" .... Slots of the non virtual classes “[dl]CHM(super|simpl)”:
p:"integer" of pointers, one
for each column, to the initial (zero-based) index of elements in
the column. Only present in classes that contain "CHMsimpl".i:"integer" of length nnzero
(number of non-zero elements). These are the row numbers for
each non-zero element in the matrix. Only present in classes that
contain "CHMsimpl".x:"d*" classes: "numeric" - the
non-zero elements of the matrix.signature(from = "CHMfactor", to = "sparseMatrix")signature(x = "CHMfactor")signature(a = "CHMfactor", b = "ddenseMatrix")
The solve methods for a "CHMfactor" object take an
optional third argument system whose value can be one of the
character strings "A", "LDLt", "LD",
"DLt", "L", "Lt", "D", "P" or
"Pt". This argument describes the system to be solved. The
default is to solve Ax = b for x where A is
sparse, positive-definite matrix that was factored to produce
"a".signature(a = "CHMfactor", b = "dsparseMatrix")signature(a = "CHMfactor", b = "matrix")
Cholesky, also for examples;
class dgCMatrix.