This code snippet produces a simple GUI, calling a Scilab function or script. Here we call the function plot3d() without argument that generates a 3D graph:

f = createWindow();
f.axes_size = [230 180];
f.figure_name = "My Interface";
uicontrol(f,...
    "style", "pushbutton",...
    "string","Call my script",...
    "position", [50 75 130 40],...
    "callback", "plot3d");