#WBL 12 Mar 2005 For Chapter 2 www pages. Needs gnuplot 4 #WBL 11 Jan 2001 created set term gif set out "landscapespiral.gif" set title "100-5*radius(x,y)+radius(x,y)*cos(R(x,y))" set label "Foundation of Genetic Programming page 20" at 30,20,-200 right set nokey set xrange [-20:20] set yrange [-20:20] set pm3d at s hidden3d 100 set style line 100 lt 1 lw 0.5 unset hidden3d unset surf set isosample 100 set ticslevel 0 radius(x,y) = (x*x+y*y)**0.5; R(x,y) = radius(x,y)+atan2(x,y); splot 100-5*radius(x,y)+radius(x,y)*cos(R(x,y)) #pause -1