CrossRatio Command
From GeoGebra Manual
- CrossRatio( <Point A>, <Point B>, <Point C>, <Point D> )
- Calculates the cross ratio λ of four collinear points A, B, C and D, where:
λ = AffineRatio[B, C, D] / AffineRatio[A, C, D]. - Example:
CrossRatio((-1, 1), (1, 1), (3, 1), (4, 1))
yields 1.2