search for: btens

...program (it works in a 2-dimensional setting) library(splines) # set the break-points Knots = seq(-1,1,length=10) # number of splines M = (length(Knots)-4)^2 # short cut to splineDesign function bspline = function(x) splineDesign(Knots,x,outer.ok = T) # bivariate tensor product of bspline btens = function(x) t(bspline(x[1]))%*%bspline(x[2]) # numebr of points to plot ng = 51 # create vectors for plotting xgr = seq(-1,1,length=ng) xgr2 = expand.grid(xgr,xgr) # generate random coef. of linear combination bet = rnorm(M) # create matrix for contour-type plot Bx = apply(xg...