# complex

Construct complex `fi` object from real and imaginary parts

## Syntax

``c = complex(a,b)``
``c = complex(x)``

## Description

example

````c = complex(a,b)` creates a complex output, `c`, from two real inputs, such that ```c = a + bi```.When `b` is all zero, `c` is complex with an all-zero imaginary part. This is in contrast to the addition of `a + 0i`, which returns a strictly real result.```

example

````c = complex(x)` returns the complex equivalent of `x`, such that `isreal(c)` returns logical `0` (`false`). If `x` is real, then `c` is ```x + 0i```.If `x` is complex, then `c` is identical to `x`. ```

## Examples

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Use the `complex` function to create the complex scalar, `3 + 4i`.

```a = fi(3,1,16,12); b = fi(4,0,8); c = complex(a,b)```
```c = 3.0000 + 4.0000i DataTypeMode: Fixed-point: binary point scaling Signedness: Signed WordLength: 16 FractionLength: 12```

The output, `c`, has the same `numerictype` and `fimath` properties as the input `fi` object, `a`.

Create a complex `fi` vector with a zero imaginary part.

```x = fi([1;2;3;4]); c = complex(x)```
```c = 1.0000 + 0.0000i 2.0000 + 0.0000i 3.0000 + 0.0000i 4.0000 + 0.0000i DataTypeMode: Fixed-point: binary point scaling Signedness: Signed WordLength: 16 FractionLength: 12```

Verify that `c` is complex.

`isreal(c)`
```ans = logical 0```

## Input Arguments

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Real component, specified as a `fi` scalar, vector, matrix, or multidimensional array.

The size of `a` must match the size of `b`, unless one is a scalar. If either `a` or `b` is a scalar, MATLAB® expands the scalar to match the size of the other input.

Data Types: `fi`

Imaginary component, specified as a `fi` scalar, vector, matrix, or multidimensional array.

The size of `b` must match the size of `a`, unless one is a scalar. If either `a` or `b` is a scalar, MATLAB expands the scalar to match the size of the other input.

Data Types: `fi`

Input array, specified as a `fi` scalar, vector, matrix, or multidimensional array.

Data Types: `fi`

## Output Arguments

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Complex array, returned as a `fi` scalar, vector, matrix, or multidimensional array.

The size of `c` is the same as the input arguments.

The output `fi` object, `c`, has the same `numerictype` and `fimath` properties as the input `fi` object, `a`.

## Version History

Introduced before R2006a