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# BitMaskClear

Performs a bitwise mask clear operation.

## Method Signature

```
BitMaskClear(number=[integer], start=[integer], length=[integer])
```

### Arguments

| Argument | Type      | Required | Description                                                              | Default |
| -------- | --------- | -------- | ------------------------------------------------------------------------ | ------- |
| `number` | `integer` | `true`   | 32-bit signed integer on which the mask clear operation is performed.    |         |
| `start`  | `integer` | `true`   | Start bit for the clear mask (Integer in the range 0-31, inclusive).     |         |
| `length` | `integer` | `true`   | Length of bits in the clear mask (Integer in the range 0-31, inclusive). |         |

## Examples

### Bitwise Mask Clear

Uses the bitMaskClear function to clear (setting to 0) each of the corresponding bits

[Run Example](https://try.boxlang.io/?code=eJxLyizxTSzOds5JTSzSUDDWUTDQUTBU0LTmAgBqAQa1)

```java
bitMaskClear( 3, 0, 1 );

```

Result: 2

### Using non zero start parameter

[Run Example](https://try.boxlang.io/?code=eJxLyizxTSzOds5JTSzSUDDWUTAEIgVNay4AagkGtg%3D%3D)

```java
bitMaskClear( 3, 1, 1 );

```

Result: 1

### Using non zero mask start and length parameters

[Run Example](https://try.boxlang.io/?code=eJxLyizxTSzOds5JTSzSUDA00FEw1FEwUtC05gIAcTQG5Q%3D%3D)

```java
bitMaskClear( 10, 1, 2 );

```

Result: 8

### Additional Examples

[Run Example](https://try.boxlang.io/?code=eJwrL8osSfUvLSkoLdFQSMos8U0sznbOSU0s0lAwMjXVUQAhBU0FTWuucmSVSjZJRXZKGMJYDDDQUTCBGAAAOmkgBQ%3D%3D)

```java
writeOutput( bitMaskClear( 255, 5, 5 ) );
writeOutput( "<br>" );
writeOutput( bitMaskClear( 255, 0, 4 ) );

```

## Related

* [BinaryDecode](/boxlang-language/reference/built-in-functions/binary/binarydecode.md)
* [BinaryEncode](/boxlang-language/reference/built-in-functions/binary/binaryencode.md)
* [BitAnd](/boxlang-language/reference/built-in-functions/binary/bitand.md)
* [BitMaskRead](/boxlang-language/reference/built-in-functions/binary/bitmaskread.md)
* [BitMaskSet](/boxlang-language/reference/built-in-functions/binary/bitmaskset.md)
* [BitNot](/boxlang-language/reference/built-in-functions/binary/bitnot.md)
* [BitOr](/boxlang-language/reference/built-in-functions/binary/bitor.md)
* [BitSh](/boxlang-language/reference/built-in-functions/binary/bitsh.md)
* [bitShln](/boxlang-language/reference/built-in-functions/binary/bitshln.md)
* [bitShrn](/boxlang-language/reference/built-in-functions/binary/bitshrn.md)
* [BitXor](/boxlang-language/reference/built-in-functions/binary/bitxor.md)


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