clear — Clear variables from the active workspace.

clear removes variables from the active RunMat workspace. RunMat supports MATLAB-style clear, clear all, and named-variable forms such as clear x or clear x y, updating the session snapshot so removed variables disappear from subsequent workspace queries.

How clear works

• clear with no inputs clears all workspace variables created in the current session.
• clear('all') and command-form clear all are treated the same as bare clear.
• clear x removes the variable x while leaving other workspace bindings intact.
• Multiple names can be supplied as separate inputs or command-form tokens, for example clear x y z.
• After a successful clear, removed variables are no longer available to later statements and the workspace snapshot is refreshed so hosts can drop cleared bindings.
• Accepts variable names as string scalars, row character vectors, or string arrays. If any input is all, the entire workspace is cleared.
• Clearing a name that does not exist is a no-op.
• clear is a sink builtin and does not produce a meaningful output value.

How RunMat runs clear on the GPU

clear performs host-side workspace mutation only. It does not launch GPU kernels, does not participate in fusion, and does not depend on acceleration providers.

Examples

Clear the entire interactive workspace

x = 1;
y = magic(3);
clear

Expected output:

% x and y are removed from the workspace

Use MATLAB-style command form

a = 42;
clear all

Expected output:

% a is removed from the workspace

Accessing a cleared variable raises an error

x = 7;
clear;
x

Expected output:

Undefined variable: x

Clear one variable while leaving others intact

x = 1;
y = 2;
clear x

Expected output:

% x is removed from the workspace while y remains defined

Clear multiple named variables in command form

a = 1;
b = 2;
c = 3;
clear a b

Expected output:

% a and b are removed; c remains defined

FAQ

Related Introspection functions

Open-source implementation

Unlike proprietary runtimes, every RunMat function is open-source. Read exactly how clear works, line by line, in Rust.

• View clear.rs on GitHub
• Learn how the runtime works
• Found a bug? Open an issue with a minimal reproduction.

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