swissroll {gasper}

Swiss Roll Graph Generation

Description

Generates points for a Swiss roll graph. The function maps points from the square [0,1]^2 into the Swiss roll using the specified transformations.

Usage

swissroll(N = 500, seed = NULL, a = 1, b = 4)

Arguments

N

Number of points drawn (numeric).

seed

Optionally specify a RNG seed for reproducible experiments (numeric).

a, b

Shape parameters (numeric).

Details

Given points (x,y) within the unit square [0,1]^2, the Swiss roll transformation is achieved using: Sx = \pi \sqrt{(b^2 - a^2) x + a^2} and Sy = \frac{\pi^2 (b^2 - a^2) y}{2}. The transformed (x,y) coordinates are then projected into 3D space to produce the characteristic rolled shape.

Value

N x 3 array for 3d points.

See Also

adjacency_mat

Examples

## Not run: 
pts <- swissroll(N=500, seed=0, a=1, b=4)
plot3D::scatter3D(pts[,1], pts[,2], pts[,3], colvar=NULL, col="red")

## End(Not run)