isreal - check if a variable as real or complex entries

Calling Sequence

t=isreal(x)

t=isreal(x,eps)

Parameters

• x : vector or matrix with floating point entries or coefficients
• t : a boolean

Description

isreal(x) returns true if x is stored as a real variable and false if x is stored with an (eventually zero) imaginary part.

isreal(x,eps) returns true if x is stored as a real variable or if maximum absolute value of imaginary floating points if less or equal than eps.

Examples

isreal([1 2])
isreal(1+0*%i)
isreal(1+0*%i,0)
isreal(1+%s)
isreal(sprand(3,3,0.1))