19.7.2 3D parametric surface
To draw a parametric surface in ℝ
3
:
plotparam
takes two mandatory arguments and two optional arguments:
exprs
, a list of three expressions involving two parameters.
vars
, a list of the parameters, optionally with a range
var
=
a
..
b
.
Optionally,
ustep=
n
, to set the discretization step of the first parameter.
Optionally,
vstep=
m
, to set the discretization step of the second parameter.
plotparam(
exprs
,
vars
⟨,
ustep=
n
,
vstep=
m
⟩
)
draws the parametric representation of the surface.
Examples
plotparam
([
v
*
cos
(
u
),
v
*
sin
(
u
),
v
],[
u
,
v
])
plotparam
([
v
*
cos
(
u
),
v
*
sin
(
u
),
v
],[
u
=0..
pi
,
v
=0..3])
plotparam
([
v
*
cos
(
u
),
v
*
sin
(
u
),
v
],[
u
=0..
pi
,
v
=0..3],
ustep
=0.5,
vstep
=0.5)
