MATLAB Function Reference 
Construct complex data from real and imaginary components
Syntax
Description
c = complex(a,b)
creates a complex output, c
, from the two real inputs.
The output is the same size as the inputs, which must be scalars or equally sized vectors, matrices, or multidimensional arrays.
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.

The following describes when a
and b
can have different data types, and the resulting data type of the output c
:
a
or b
has type single
, c
has type single
.
a
or b
has an integer data type, the other must have the same integer data type or type scalar double
, and c
has the same integer data type.
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
in cases when the names "i
" and "j
" may be used for other variables (and do not equal ), when a
and b
are not single
or double
, 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
See Also
abs
, angle
, conj
, i
, imag
, isreal
, j
, real
compass  computer 
© 19942005 The MathWorks, Inc.