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Large MAT-Files

Access and change variables without loading into memory

Use the matfile function to access MATLAB® variables directly from MAT-files on disk, without loading the full variables into memory. When you create a new file using matfile, the function creates a Version 7.3 MAT-file that also lets you save variables larger than 2 GB.


matfileAccess and change variables in MAT-file without loading file into memory


  • Save and Load Workspace Variables

    Save some or all variables in the current workspace and reload the variables later during the current MATLAB session, or during another session.

  • Save and Load Parts of Variables in MAT-Files

    Save and load parts of variables directly in MAT-files without loading them into memory using the matfile function.

  • MAT-File Versions

    There are several versions of MAT-files that each support an increasing set of features, starting with MAT-file Version 4.


Growing Arrays Using matfile Function

When writing a large number of large values to a MAT-file, the size of the file increases in a nonincremental way, which is expected.