等高線グラフでスーパー楕円を描画する

superelipse.r

n <- 100 # num. of mesh
a <- 1.0 # x-axis param
b <- 1.0 # y-axis param
r <- 2.5 # when r is 2.5, it's superelipse
x <- seq( -a, a, length = n )
y <- seq( -b, b, length = n )
z <- matrix(0, n, n)
for (i in 1:n) {
  for (j in 1:n) {
    # superelipse
    z[i, j] <- abs(x[i]/a) ^ r + abs(y[j]/b) ^ r
  }
}
contour(x, y, z, drawlabels = F, levels=1, asp=1, lwd=12)