MATLAB Function Reference

load

Load workspace variables from disk

Syntax

• load
  load filename
  load filename X Y Z
  load filename -ascii
  load filename -mat
  S = load(...)
  

Description

load loads all the variables from the MAT-file matlab.mat, if it exists, and returns an error if it doesn't exist.

load filename loads all the variables from filename given a full pathname or a MATLABPATH relative partial pathname. If filename has no extension, load looks for file named filename or filename.mat and treats it as a binary MAT-file. If filename has an extension other than .mat, load treats the file as ASCII data.

load filename X Y Z ... loads just the specified variables from the MAT-file. The wildcard '*' loads variables that match a pattern (MAT-file only).

load -ascii filename or load -mat filename forces load to treat the file as either an ASCII file or a MAT-file, regardless of file extension. With -ascii, load returns an error if the file is not numeric text. With -mat, load returns an error if the file is not a MAT-file.

load -ascii filename returns all the data in the file as a single two dimensional double array with its name taken from the filename (minus any extension). The number of rows is equal to the number of lines in the file and the number of columns is equal to the number of values on a line. An error occurs if the number of values differs between any two rows.

load filename.ext reads ASCII files that contain rows of space-separated values. The resulting data is placed into a variable with the same name as the file (without the extension). ASCII files may contain MATLAB comments (lines that begin with %).

If filename is a MAT-file, load creates the requested variables from filename in the workspace. If filename is not a MAT-file, load creates a double precision array with a name based on filename. load replaces leading underscores or digits in filename with an X and replaces other non-alphabetic character with underscores. The text file must be organized as a rectangular table of numbers, separated by blanks, with one row per line, and an equal number of elements in each row.

S = load(...) returns the contents of a MAT-file in the variable S. If the file is a MAT-file, S is a struct containing fields that match the variables in retrieved. When the file contains ASCII data, S is a double-precision array.

Use the functional form of load, such as load('filename'), when the file name is stored in a string, when an output argument is requested, or if filename contains spaces. To specify a command line option with this functional form, specify the option as a string argument, including the hyphen. For example,

• load('myfile.dat','-mat')
  

Remarks

MAT-files are double-precision binary MATLAB format files created by the save command and readable by the load command. They can be created on one machine and later read by MATLAB on another machine with a different floating-point format, retaining as much accuracy and range as the disparate formats allow. They can also be manipulated by other programs, external to MATLAB.

The Application Program Interface Libraries contain C- and Fortran-callable routines to read and write MAT-files from external programs.

See Also

fprintf, fscanf, partialpath, save, spconvert

listdlg

load (COM)