Groups

Groups are lists of matrix names and we use them to categorize matrices in Matrix Depot. The list below shows all the predefined groups in Matrix Depot and we can extend this list by defining new groups. Group names are noted as symbols, e.g. :symmetric.

Predefined Groups

all

All the matrices in the collection.

data

The matrix has been downloaded from UF sparse matrix collection or the Matrix Market collection.

eigen

Part of the eigensystem of the matrix is explicitly known.

graph

An adjacency matrix of a graph.

illcond

The matrix is ill-conditioned for some parameter values.

inverse

The inverse of the matrix is known explicitly.

posdef

The matrix is positive definite for some parameter values.

random

The matrix has random entries.

regprob

The output is a test problem for Regularization Methods.

sparse

The matrix is sparse.

symmetric

The matrix is symmetric for some parameter values.

Adding New Groups

New groups can be added with the function setgroup! in the REPL:

julia> setgroup!(:myfav, ["lehmer", "cauchy", "hilb"])
julia> setgroup!(:test_for_paper2, ["tridiag", "sampling", "wing"])

julia> listgroups()
14-element Array{Symbol,1}:
:all
:builtin
:local
:user
:eigen
:graph
:illcond
:inverse
:posdef
:random
:regprob
:sparse
:symmetric
:myfav
:test_for_paper2

julia> listnames(:myfav)
list(3)
––––––– –––– ––––––
cauchy  hilb lehmer