Class TensorWriter

java.lang.Object
org.flag4j.io.TensorWriter
public final class TensorWriter extends Object

The TensorWriter class provides static methods for serializing and saving tensors, matrices, and vectors to files. Supported formats include:

  • Binary serialization using ObjectOutputStream
  • Comma-separated values (CSV) format for dense real, complex, and field matrices
  • Matrix Market Exchange Format for dense and sparse (COO or CSR) matrices (real or complex). Both COO and CSR matrices are written in the coordinate (COO) format. Symmetry is not considered and all matrices will be written as general matrices regardless of the symmetry.

Usage Example


 // Write a real matrix to a Matrix Market Exchange Format file
 Matrix matrix1 = new Matrix(...);
 TensorWriter.toMatrixMarket("matrix1.mtx", matrix1);

 // Write a complex COO matrix to a Matrix Market Exchange Format file
 CooCMatrix cooMatrix = new CooCMatrix(...);
 TensorWriter.toMatrixMarket("cooMatrix.mtx", cooMatrix, "this is a comment");

 // Write a real matrix to a CSV file
 Matrix matrix2 = new Matrix(...);
 TensorWriter.toCsv("matrix2.csv", matrix2);
 TensorWriter.toCsv("matrix2.csv", matrix2, ";");  // Specify delimiter.

 // Serialize a tensor to a binary file
 AbstractTensor tensor = new AbstractTensor(...);
 TensorWriter.write("tensor.ser", tensor);

  • Method Details

    • write

      public static void write(String fileName, AbstractTensor<?,?,?> src) throws IOException
      Writes a tensor to a file using a ObjectOutputStream. If the write operation fails it will terminate but no exception will be thrown. To determine if the write was successful, see the return value: if the write was successful, true is returned; if the write fails,then false is returned. is returned.
      Parameters:
      fileName - File name, including extension, of the file to write the serialized matrix to.
      src - Source object to write to the specified file.
      Throws:
      IOException - If any I/O error occurs when attempting to write to file.

    • toMatrixMarket

      public static void toMatrixMarket(String fileName, MatrixMixin<?,?,?,?> src, String... comments) throws IOException

      Writes a matrix to a Matrix Market Exchange Format file.

      If src is a CSR matrix, it will be converted to a COO matrix and saved as a coordinate matrix. All matrices are stored in general form regardless of the symmetry.

      Supported matrices:

      • 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:
      fileName - Path of the file to write to.
      src - Matrix to write to file.
      comments - Comments to prepend to file. Each comment will be written to its own line. May be null or length zero (i.e. nothing passed); in this case the parameter will be ignored.
      Throws:
      IOException - If an I/O error occurs.
      IllegalArgumentException - If src is not a supported matrix type for writing to a Matrix Market Exchange Format file.

    • toCsv

      public static void toCsv(String fileName, MatrixMixin<?,?,?,?> src) throws IOException
      Writes a matrix to a CSV file. Matrix must be an instance of either Matrix or CMatrix. Uses "," as the default delimiter. To specify the delimiter use toCsv(String, MatrixMixin, String).
      Parameters:
      fileName - Name of the file to save matrix to.
      src - Matrix to save to CSV file.
      Throws:
      IOException - If any I/O error occurs when attempting to write to file.
      See Also:

    • toCsv

      public static void toCsv(String filePath, MatrixMixin<?,?,?,?> src, String delimiter) throws IOException
      Writes a matrix to a CSV file. Matrix must be an instance of either Matrix or CMatrix.
      Parameters:
      filePath - Path of the file to save matrix to.
      src - Matrix to save to CSV file.
      Throws:
      IOException - If any I/O error occurs when attempting to write to file.
      IllegalArgumentException - If !(src instanceof Matrix || src instanceof CMatrix).
      See Also: