a := 1
a.minimum := -2
a.maximum := 2
b := 1
b.minimum := -2
b.maximum := 2
c := 1
c.minimum := -2
c.maximum := 2
d := 1
d.minimum := -2
d.maximum := 2
graph3d.box := true
graph3d.mesh := false
graph3d.view := textbook
graph3d.perspective := false
graph3d.resolution := 60
graph3d.highlight := 0
graph3d.shading := 1
graph3d.contrast := 1/2
graph3d.transparency := 0.2
graph3d.color := gray
graph3d.background := white
graph3d.minimumx := -3
graph3d.maximumx := 3
graph3d.minimumy := -2
graph3d.maximumy := 2
graph3d.minimumz := -1
graph3d.maximumz := 1
graph3d( ( y = a*sin(2*x+time), x=0, y=0 ) )