MAT file save and load in MATLAB - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a MAT file in MATLAB?

A MAT file is a binary file format used by MATLAB to save variables and data so they can be loaded later. It stores workspace variables in a file with a .mat extension.

beginner

How do you save variables to a MAT file in MATLAB?

Use the save command. For example, save('filename.mat', 'var1', 'var2') saves variables var1 and var2 to the file named filename.mat.

beginner

How do you load variables from a MAT file in MATLAB?

Use the load command. For example, load('filename.mat') loads all variables saved in filename.mat into the workspace.

intermediate

What happens if you use load with an output variable like data = load('file.mat')?

The loaded variables are stored as fields inside the structure data. You can access variables with data.varname.

beginner

How can you save all workspace variables to a MAT file?

Use save('filename.mat') without specifying variable names. This saves all current workspace variables to the file.

Which command saves variables 'a' and 'b' to a MAT file named 'data.mat'?

A save('a', 'b', 'data.mat')

B load('data.mat', 'a', 'b')

C save('data.mat', 'a', 'b')

D load('a', 'b', 'data.mat')

The save command with the filename first and then variable names saves those variables to the MAT file.

What does load('file.mat') do in MATLAB?

A Loads variables from file.mat into the workspace

B Saves variables to file.mat

C Deletes file.mat

D Creates a new MAT file

The load command reads variables from the MAT file and puts them into the workspace.

If you want to load variables from a MAT file into a structure variable, which syntax is correct?

A save('file.mat', data)

B data = load('file.mat')

C load('file.mat', data)

D load data = 'file.mat'

Assigning the output of load to a variable stores the loaded variables as fields in that structure.

How do you save all current workspace variables to a MAT file named 'allvars.mat'?

A save('allvars.mat')

B save('allvars.mat', '*')

C load('allvars.mat')

D save allvars.mat

Calling save with only the filename saves all workspace variables to that MAT file.

What file extension do MATLAB MAT files use?

A .txt

B .matlab

C .m

D .mat

MAT files use the .mat extension to store MATLAB variables.

Explain how to save specific variables to a MAT file and then load them back into MATLAB workspace.

Think about the save and load commands and how you name variables.

Describe what happens when you load a MAT file into a structure variable and how to access the saved variables.

Consider the difference between loading directly and loading into a variable.