## Rotation

A rotation can be defined in two different ways: One way is by choosing the mode Rotation P|Ang, which defines a rotation by a rotation center and an angle (which is given by a number). To apply this mode one has to click the center of a rotation and a text in the drawing that represents the requested angle (for instance a measured angle). Alternatively, one can use Rotation LL mode. For this one has to click two different lines that serve as a sample for an image and a preimage.
The mode Rotation P|Ang can be particularly useful if the rotation angle is an already measured angle or if the rotation angle must satisfy a certain predefined value. The mode Rotation LL is useful whenever a line and its image under the rotation are already available.
The picture below shows an iterated application of a rotation to a circle.

Rotating a circle

### Caution

Rotations are also defined in hyperbolic and elliptic geometry.

### See also

- Translation
- Similarity
- Reflection

Page last modified on Thursday 08 of December, 2005 [10:43:25 UTC].
The original document is available at http://doc.cinderella.de/tiki-index.php?page=Rotation