Matrix Market provides Matlab® M-files for three basic Matrix Market file I/O functions: mminfo, mmread, and mmwrite. Their use is described here.
| File: | mminfo.m |
|---|---|
| Requires: | strtok.m from Matlab Version 4.2. If using a previous version of Matlab, substitute gettok.m |
| Function: | [rows, cols, entries, rep, field, symm] = mminfo(filename);
|
| Description: | Queries the contents of the Matrix Market file 'filename'
to extract size and storage information.
In the case of coordinate matrices, entries refers to the number of coordinate entries stored in the file, since the number of non-zero entries in the final matrix cannot be determined until the data is read (and symmetrized, if necessary). In the case of array matrices, entries is the product rows*cols, regardless of whether symmetry was used to store the matrix efficiently. |
| File: | mmread.m |
|---|---|
| Requires: | strtok.m from Matlab Version 4.2. If using a previous version of Matlab, substitute gettok.m |
| Function: | [A, rows, cols, entries] = mmread(filename);
|
| Description: | Reads the contents of the Matrix Market file 'filename'
into the matrix 'A'. 'A' will be either sparse
or full (in the Matlab sense) depending on the Matrix Market format,
indicated by '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. |
| File: | mmwrite.m | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Function: | [err] = mmwrite(filename,A,comment,field,precision);
| |||||||||||||||
| Description: |
Writes the sparse or dense matrix A to a Matrix Market
formatted file.
Arguments:
|