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MQL5 リファレンス行列とベクトルのメソッドWrite and ReadWriteBin 

WriteBin

The method writes a matrix to a file according to its size and type.

long matrix::WriteBin(
  int                file_handle     // file handle opened to write
  );

Parameters

file_handle

[in]  File descriptor returned by FileOpen().

Return Value

Returns the number of bytes written to the file. Or -1 in case of error.

Note

Writing is performed from the current file position. The file must be opened as binary for writing (FILE_BIN|FILE_WRITE flags). The matrix must have a nonzero size.