www-ai.cs.tu-dortmund.de/de/LEHRE/VORLESUNGEN/NOPT/SS14/code/contour_quad.html
matrix(c(10,0,0,5), byrow=TRUE, nrow=2, ncol=2) # convex, axis-aligned M[[3]] <- matrix(c(10,0,0,1), byrow=TRUE, nrow=2, ncol=2) # convex, axis-aligned, ill-conditioned M[[4]] <- matrix(c(10,3,3,5), byrow=TRUE [...] byrow=TRUE, nrow=2, ncol=2) # convex, not aligned to axes M[[5]] <- matrix(c(-10,0,0,-5), byrow=TRUE, nrow=2, ncol=2) # concave M[[6]] <- matrix(c(10,0,0,-10), byrow=TRUE, nrow=2, ncol=2) # neither convex nor …