`mustBeReal`

Checks that a value has no imaginary part.

Category: Programming > Functions

Syntax

mustBeReal(A)

Checks that A contains only real values. Returns nothing if the check passes and throws an error if not.

Description

mustBeReal is a validator: it inspects its input and either returns silently or raises an error with the identifier MATLAB:validators:mustBeReal. The error message states the requirement that was violated, so the caller sees what was expected rather than a generic failure.

A complex array whose imaginary parts are all zero is stored as real by MATLAB rules and therefore passes.

Input arguments

A: The value to check. Any array of the class the validator accepts.

Example

Passing and failing input

mustBeReal([1 2 3]);
disp('passed')
try
    mustBeReal(1 + 2i)
catch err
    disp(err.message)
end

Output

passed
Value must be real.

See also

isreal real imag mustBeNumeric