LOAD Load Variables From A File

Section: Input/Ouput Functions

Usage

Loads a set of variables from a file in a machine independent format. The load function takes one argument: 
  load filename,

or alternately, 

  load('filename')

This command is the companion to save. It loads the contents of the file generated by save back into the current context. Global and persistent variables are also loaded and flagged appropriately. By default, FreeMat assumes that files that end in a .mat or .MAT extension are MATLAB-formatted files. Also, FreeMat assumes that files that end in .txt or .TXT are ASCII files. For other filenames, FreeMat first tries to open the file as a FreeMat binary format file (as created by the save function). If the file fails to open as a FreeMat binary file, then FreeMat attempts to read it as an ASCII file. You can force FreeMat to assume a particular format for the file by using alternate forms of the load command. In particular, 

  load -ascii filename

will load the data in file filename as an ASCII file (space delimited numeric text) loaded into a single variable in the current workspace with the name filename (without the extension). For MATLAB-formatted data files, you can use 

  load -mat filename

which forces FreeMat to assume that filename is a MAT-file, regardless of the extension on the filename. You can also specify which variables to load from a file (not from an ASCII file - only single 2-D variables can be successfully saved and retrieved from ASCII files) using the additional syntaxes of the load command. In particular, you can specify a set of variables to load by name 

  load filename Var_1 Var_2 Var_3 ...

where Var_n is the name of a variable to load from the file. Alternately, you can use the regular expression syntax 

  load filename -regexp expr_1 expr_2 expr_3 ...

where expr_n is a regular expression (roughly as expected by regexp). Note that a simpler regular expression mechanism is used for this syntax than the full mechanism used by the regexp command. Finally, you can use load to create a variable containing the contents of the file, instead of automatically inserting the variables into the curent workspace. For this form of load you must use the function syntax, and capture the output: 

  V = load('arg1','arg2',...)

which returns a structure V with one field for each variable retrieved from the file. For ASCII files, V is a double precision matrix.

Example

Here is a simple example of save/load. First, we save some variables to a file. 
--> D = {1,5,'hello'};
--> s = 'test string';
--> x = randn(512,1);
--> z = zeros(512);
--> who
  Variable Name       Type   Flags             Size
              D      cell                    [1 3]
              s      char                    [1 11]
              x    double                    [512 1]
              z    double                    [512 512]
--> save loadsave.dat

Next, we clear the variables, and then load them back from the file. 

--> clear D s x z
--> who
  Variable Name       Type   Flags             Size
            ans    double                    [0 0]
--> load loadsave.dat
--> who
  Variable Name       Type   Flags             Size
              D      cell                    [1 3]
            ans    double                    [0 0]
              s      char                    [1 11]
              x    double                    [512 1]
              z    double                    [512 512]