# or

Logical OR for symbolic expressions

## Syntax

``A | B``
``or(A,B)``

## Description

example

````A | B` represents the logical OR. `A | B` is true when either `A` or `B` is true, or when both `A` and `B` are true.```
````or(A,B)` is equivalent to `A | B`.```

## Examples

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Combine these symbolic inequalities into a logical condition by using `|`.

```syms x y xy = x>=0 | y>=0;```

Set the assumption represented by the condition using `assume`.

`assume(xy)`

Verify that the assumptions are set.

`assumptions`
```ans = 0 <= x | 0 <= y```

Combine two symbolic inequalities into a logical expression by using `|`.

`range = x < -1 | x > 1;`

Substitute `x` with `0` and `10`. Although the inequalities have values, `subs` does not evaluate them to logical `1` or `0`.

```x1 = subs(range,x,10) x2 = subs(range,x,0)```
```x1 = 1 < 10 | 10 < -1 x2 = 0 < -1 | 1 < 0```

Evaluate the inequalities by using `isAlways`.

`isAlways(x1)`
```ans = logical 1 ```
`isAlways(x2)`
```ans = logical 0```

Combine multiple conditions by applying `or` to the conditions using the `fold` function.

Set the condition that `x` equals an integer between `1` and `10`.

```syms x cond = fold(@or, x == 1:10); assume(cond) assumptions```
```ans = x == 1 | x == 2 | x == 3 | x == 4 | x == 5 |... x == 6 | x == 7 | x == 8 | x == 9 | x == 10```

## Input Arguments

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Operands, specified as symbolic equations, inequalities, expressions, or 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.

## Version History

Introduced in R2012a

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