# plus, +

## Syntax

``C = A + B``
``C = plus(A,B)``

## Description

example

````C = A + B` adds arrays `A` and `B` by adding corresponding elements. If one input is a string array, then `plus` appends the corresponding elements as strings.The sizes of `A` and `B` must be the same or be compatible. If the sizes of `A` and `B` are compatible, then the two arrays implicitly expand to match each other. For example, if one of `A` or `B` is a scalar, then the scalar is combined with each element of the other array. Also, vectors with different orientations (one row vector and one column vector) implicitly expand to form a matrix.```
````C = plus(A,B)` is an alternate way to execute `A + B`, but is rarely used. It enables operator overloading for classes.```

## Examples

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Create an array, `A`, and add a scalar value to it.

```A = [0 1; 1 0]; C = A + 2```
```C = 2×2 2 3 3 2 ```

The scalar value is added to each entry of `A`.

Create two 1-by-3 string arrays, then append similarly located strings in the arrays.

`s1 = ["Red" "Blue" "Green"]`
```s1 = 1x3 string "Red" "Blue" "Green" ```
`s2 = ["Truck" "Sky" "Tree"]`
```s2 = 1x3 string "Truck" "Sky" "Tree" ```
`s = s1 + s2`
```s = 1x3 string "RedTruck" "BlueSky" "GreenTree" ```

Create two arrays, `A` and `B`, and add them together.

```A = [1 0; 2 4]; B = [5 9; 2 1]; C = A + B```
```C = 2×2 6 9 4 5 ```

The elements of `A` are added to the corresponding elements of `B`.

Create a 1-by-2 row vector and 3-by-1 column vector and add them.

```a = 1:2; b = (1:3)'; a + b```
```ans = 3×2 2 3 3 4 4 5 ```

The result is a 3-by-2 matrix, where each (i,j) element in the matrix is equal to a`(j) + b(i)`:

`$\mathit{a}=\left[{\mathit{a}}_{1}\text{\hspace{0.17em}}{\mathit{a}}_{2}\right],\text{\hspace{0.17em}}\text{\hspace{0.17em}}\text{\hspace{0.17em}}\text{\hspace{0.17em}}\text{\hspace{0.17em}}\text{\hspace{0.17em}}\text{\hspace{0.17em}}\text{\hspace{0.17em}}\text{\hspace{0.17em}}\text{\hspace{0.17em}}\mathit{b}=\left[\begin{array}{c}{\mathit{b}}_{1}\\ {\mathit{b}}_{2}\\ {\mathit{b}}_{3}\end{array}\right],\text{\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}}\text{\hspace{0.17em}}\mathit{a}+\text{\hspace{0.17em}}\mathit{b}=\left[\begin{array}{cc}{\mathit{a}}_{1}+\text{\hspace{0.17em}}{\mathit{b}}_{1}& {\mathit{a}}_{2}+\text{\hspace{0.17em}}{\mathit{b}}_{1}\\ {\mathit{a}}_{1}+\text{\hspace{0.17em}}{\mathit{b}}_{2}& {\mathit{a}}_{2}+\text{\hspace{0.17em}}{\mathit{b}}_{2}\\ {\mathit{a}}_{1}+\text{\hspace{0.17em}}{\mathit{b}}_{3}& {\mathit{a}}_{2}+\text{\hspace{0.17em}}{\mathit{b}}_{3}\end{array}\right].$`

Create an array, `A`, and add a column vector to it. The vector is treated as though it is a matrix of the same size as `A`, so that each element in the vector is added to a row in `A`.

`A = [1 2 3; 4 5 6]`
```A = 2×3 1 2 3 4 5 6 ```
`b = [10; 100]`
```b = 2×1 10 100 ```
`A + b`
```ans = 2×3 11 12 13 104 105 106 ```

## Input Arguments

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Operands, specified as scalars, vectors, matrices, or multidimensional arrays. Inputs `A` and `B` must either be the same size or have sizes that are compatible (for example, `A` is an `M`-by-`N` matrix and `B` is a scalar or `1`-by-`N` row vector). For more information, see Compatible Array Sizes for Basic Operations.

• If one input is a string array, then the other input can be numeric, character, string, or a cell array. In this case, `plus` converts the non-string input into a string array and then appends corresponding elements of the inputs.

• Operands with an integer data type cannot be complex.

• If one input is a `datetime` array, `duration` array, or `calendarDuration` array, then numeric values in the other input are treated as a number of 24-hour days.

Data Types: `single` | `double` | `int8` | `int16` | `int32` | `int64` | `uint8` | `uint16` | `uint32` | `uint64` | `logical` | `char` | `string` | `datetime` | `duration` | `calendarDuration`
Complex Number Support: Yes

## Tips

• For appending text, `plus` only operates on string arrays. Use the `append` function to append text in character vectors or cell arrays.

## Compatibility Considerations

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Behavior changed in R2016b

Behavior changed in R2020b