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.
- symmetric
The matrix is symmetric for some parameter values.
- inverse
The inverse of the matrix is known explicitly.
- illcond
The matrix is ill-conditioned for some parameter values.
- posdef
The matrix is positive definite for some parameter values.
- eigen
Part of the eigensystem of the matrix is explicitly known.
- sparse
The matrix is sparse.
- random
The matrix has random entries.
- data
The matrix has been downloaded from UF sparse matrix collection or the Matrix Market collection.
- regprob
The output is a test problem for Regularization Methods.
- all
All the matrices in the collection.
- graph
An adjacency matrix of a graph.
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