# `GSFrameView zoomViewByFactor:`

*Instance Method*

Zoom by the desired scaling factor.

## Declaration

```swift
func zoom(byFactor factor: CGFloat)
```

```objc
- (void) zoomViewByFactor:(CGFloat) factor;
```

```python
zoomViewByFactor_(factor: float)
```

## Discussion

A factor of 2.0 will double the zoom scale, from 100% to 200% say, a factor of 0.5 will zoom out. This also maintains the current visible centre point of the view so the zoom remains stable.