isempty - Determine whether dynamic system model is empty

Syntax

Description

isempty(sys) returns TRUE (logical 1) if the dynamic system model sys has no input or no output, and FALSE (logical 0) otherwise. Where sys is a FRD model, isempty(sys) returns TRUE when the frequency vector is empty. Where sys is a model array, isempty(sys) returns TRUE when the array has empty dimensions or when the LTI models in the array are empty.

Examples

Both commands

isempty(tf)   % tf by itself returns an empty transfer function
isempty(ss(1,2,[],[]))

return TRUE (logical 1) while

isempty(ss(1,2,3,4))

returns FALSE (logical 0).

See Also

issiso | size

Free Control Systems Interactive Kit

Learn more about resources for designing, testing, and implementing control systems.

Get free kit

Trials Available

Try the latest control systems products.

Get trial software