Reads a Matrix Market file
A = mmread(filename) [A,rows] = mmread(filename) [A,rows,cols] = mmread(filename) [A,rows,cols,entries] = mmread(filename) [A,rows,cols,entries,rep] = mmread(filename) [A,rows,cols,entries,rep,field] = mmread(filename) [A,rows,cols,entries,rep,field,symm] = mmread(filename) [A,rows,cols,entries,rep,field,symm,comments] = mmread(filename)
a 1-by-1 matrix of strings, path of the Matrix Market file.
a matrix of type 1 (real or complex matrix), 4 (boolean matrix), 5 (sparse matrix) or 6 (sparse boolean matrix).
a 1-by-1 real matrix, number of matrix rows
a 1-by-1 real matrix, number of matrix columns
a 1-by-1 real matrix, number of nonzeros entries in the matrix
a 1-by-1 matrix of strings, with values "coordinate" or "array"
a 1-by-1 matrix of strings, with values "real", "complex" or "pattern"
a 1-by-1 matrix of strings, with values "general", "symmetric", "skew-symmetric", "hermitian"
a 1-by-n matrix of strings, contains the comments present in the file header.
Reads the contents of the Matrix Market file filename
into the matrix A
. A
will be either sparse or full,
depending on the Matrix Market format indicated by rep
'coordinate' (coordinate sparse storage), or
'array' (dense array storage). The data will be duplicated
as appropriate if symmetry is indicated in the header.
Optionally, size information about the matrix can be
obtained by using the return values rows
, cols
, and
entries
, where entries
is the number of nonzero entries
in the final matrix. Type information can also be retrieved
using the optional return values rep
(representation), field
,
and symm
(symmetry).
filename = fullfile(mmgetpath(),"tests","unit_tests","A.mtx"); A1=mmread(filename) A2=sparse([1,1;1,3;2,2;3,1;3,3;3,4;4,3;4,4],.. [9;27+%i;16;27-%i;145;88;88;121],[4,4]) | ![]() | ![]() |
In the following example, we use all the output arguments of the mmread function.
filename = fullfile(mmgetpath(),"tests","unit_tests","A.mtx"); [A,rows,cols,entries,rep,field,symm,comments]=mmread(filename) | ![]() | ![]() |
In the following example, we analyze a sparse file downloaded from http://math.nist.gov/MatrixMarket.
path = fullfile(mmgetpath ( ),"tests","unit_tests"); filename=fullfile(path,"ash331.mtx"); A = mmread(filename); PlotSparse(A); | ![]() | ![]() |
Copyright (C) 2009 - INRIA - Serge Steer
Copyright (C) 2011 - Benoit Goepfert
Copyright (C) 2011 - DIGITEO - Michael Baudin
http://math.nist.gov/MatrixMarket/formats.html
http://math.nist.gov/MatrixMarket/mmio/matlab/mmread.m