this should close #69

scripts/gradients.m

@@ -7,7 +7,9 @@ tx = ty = linspace (-2, 2, 21)';
 tz = xx.^2 + 4*yy.^3-12*yy-2;
 
 surf(tx, ty, tz)
-
+xlabel("x")
+ylabel("y")
+zlabel("f(x,y)")
 hold on
 
 % [x, y] = meshgrid (-2:0.2:2);