MATLAB Function Reference
complex

Construct complex data from real and imaginary components

Syntax

• c = complex(a,b)
c = complex(a)

Description

c = complex(a,b) creates a complex output, c, from the two real inputs.

• c = a + bi

The output is the same size as the inputs, which must be scalars or equally sized vectors, matrices, or multi-dimensional arrays of the same data type.

 Note    If b is all zeros, c is complex and the value of all its imaginary components is 0. In contrast, the result of the addition a+0i returns a strictly real result.

c = complex(a) for real a returns the complex result c with real part a and 0 as the value of all imaginary components. Even though the value of all imaginary components is 0, c is complex and isreal(c) returns false.

The complex function provides a useful substitute for expressions such as

• a + i*b   or   a + j*b

in cases when the names "i" and "j" may be used for other variables (and do not equal ), when a and b are not double-precision, or when b is all zero.

Example

Create complex uint8 vector from two real uint8 vectors.

• a = uint8([1;2;3;4])
b = uint8([2;2;7;7])
c = complex(a,b)
c =
1.0000 + 2.0000i
2.0000 + 2.0000i
3.0000 + 7.0000i
4.0000 + 7.0000i