Class MatrixMarketWriter

java.lang.Object

org.flag4j.io.MatrixMarketWriter

public final class MatrixMarketWriter
extends Object

A utility class for writing matrices (from the Flag4j library) to a file in the Matrix Market Exchange Format.

This class supports writing both dense and sparse matrices (real, complex, or pattern) to the Matrix Market format. Dense matrices are written in the array (dense) format, while sparse (both COO and CSR) matrices are written in the coordinate (COO) format.

If the matrix is symmetric/Hermitian it will be detected during the write and the appropriate header will be formed.

Currently Supported Matrix Types:

• Matrix (real dense)
• CMatrix (complex dense)
• CooMatrix (real sparse COO)
• CsrMatrix (real sparse CSR, converted to COO)
• CooCMatrix (complex sparse COO)
• CsrCMatrix (complex sparse CSR, converted to COO)

Attempting to write a matrix type not listed above will result in an IllegalArgumentException.

See Also:

• MatrixMarketReader
• MatrixMarketHeader

Method Summary

Modifier and Type	Method	Description
static void	write(String filePath, MatrixMixin<?,?,?,?> mat, boolean isPattern, String... comments)	Writes a matrix to a file in Matrix Market Exchange Format file.
static void	write(String filePath, MatrixMixin<?,?,?,?> mat, String... comments)	Writes a matrix to a file in Matrix Market Exchange Format file.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

write

public static void write(String filePath,
 MatrixMixin<?,?,?,?> mat,
 String... comments)
                  throws IOException

Writes a matrix to a file in Matrix Market Exchange Format file.

If mat is a CSR matrix, it will be converted to a COO matrix and saved as a coordinate matrix.

Currently supported matrix types:

• Matrix (real dense)
• CMatrix (complex dense)
• CooMatrix (real sparse COO)
• CsrMatrix (real sparse CSR, converted to COO)
• CooCMatrix (complex sparse COO)
• CsrCMatrix (complex sparse CSR, converted to COO)

To specify that a matrix should be written as a pattern matrix use write(String, MatrixMixin, boolean, String...).

Parameters:

filePath - Path of the file to write to.

mat - Matrix to write to file.

comments - Comments to prepend to file. Each comment will be written to its own line. May be null; in this case the parameter will be ignored.

Throws:

IOException - If an I/O error occurs.

IllegalArgumentException - If mat is not a supported matrix type for writing to a Matrix Market Exchange Format file.

See Also:

• write(String, MatrixMixin, boolean, String...)

write

public static void write(String filePath,
 MatrixMixin<?,?,?,?> mat,
 boolean isPattern,
 String... comments)
                  throws IOException

Writes a matrix to a file in Matrix Market Exchange Format file.

If mat is a CSR matrix, it will be converted to a COO matrix and saved as a coordinate matrix.

Currently supported matrix types:

• Matrix (real dense)
• CMatrix (complex dense)
• CooMatrix (real sparse COO)
• CsrMatrix (real sparse CSR, converted to COO)
• CooCMatrix (complex sparse COO)
• CsrCMatrix (complex sparse CSR, converted to COO)

Parameters:

filePath - Path of the file to write to.

mat - Matrix to write to file.

isPattern - Flag indicating if mat should be written as a pattern matrix (true) or not (false).

comments - Comments to prepend to file. Each comment will be written to its own line. May be null; in this case the parameter will be ignored.

Throws:

IOException - If an I/O error occurs.

IllegalArgumentException - If mat is not a supported matrix type for writing to a Matrix Market Exchange Format file.

See Also:

• write(String, MatrixMixin, String...)