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# CFMutableBitVector

```
class CFMutableBitVector
```

## Overview

CFMutableBitVector objects manage dynamic bit vectors. The basic interface for managing bit vectors is provided by [`CFBitVector`](/documentation/CoreFoundation/CFBitVector). CFMutableBitVector adds functions to modify the contents of a bit vector.

You create a mutable bit vector object using either the [`CFBitVectorCreateMutable(_:_:)`](/documentation/CoreFoundation/CFBitVectorCreateMutable(_:_:)) or [`CFBitVectorCreateMutableCopy(_:_:_:)`](/documentation/CoreFoundation/CFBitVectorCreateMutableCopy(_:_:_:)) function. You add to and remove from a bit vector by altering the size of the bit vector with the [`CFBitVectorSetCount(_:_:)`](/documentation/CoreFoundation/CFBitVectorSetCount(_:_:)) function

## Topics

### Creating a CFMutableBitVector Object

[`CFBitVectorCreateMutable(_:_:)`](/documentation/CoreFoundation/CFBitVectorCreateMutable(_:_:))

Creates a mutable bit vector.

[`CFBitVectorCreateMutableCopy(_:_:_:)`](/documentation/CoreFoundation/CFBitVectorCreateMutableCopy(_:_:_:))

Creates a new mutable bit vector from a pre-existing bit vector.

### Modifying a Bit Vector

[`CFBitVectorFlipBitAtIndex(_:_:)`](/documentation/CoreFoundation/CFBitVectorFlipBitAtIndex(_:_:))

Flips a bit value in a bit vector.

[`CFBitVectorFlipBits(_:_:)`](/documentation/CoreFoundation/CFBitVectorFlipBits(_:_:))

Flips a range of bit values in a bit vector.

[`CFBitVectorSetAllBits(_:_:)`](/documentation/CoreFoundation/CFBitVectorSetAllBits(_:_:))

Sets all bits in a bit vector to a particular value.

[`CFBitVectorSetBitAtIndex(_:_:_:)`](/documentation/CoreFoundation/CFBitVectorSetBitAtIndex(_:_:_:))

Sets the value of a particular bit in a bit vector.

[`CFBitVectorSetBits(_:_:_:)`](/documentation/CoreFoundation/CFBitVectorSetBits(_:_:_:))

Sets a range of bits in a bit vector to a particular value.

[`CFBitVectorSetCount(_:_:)`](/documentation/CoreFoundation/CFBitVectorSetCount(_:_:))

Changes the size of a mutable bit vector.


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