Use the buttons down the right hand side to construct the parametric equations
given earlier. The lower panel is for changing the camera position and direction -
1.choose what you want to change in the list on the left
2.enter what you want to change it to in the text box on the right
3.click the button in the middle to effect the change.
To construct a completely general 3D curve enter the fourier coefficients of the cosine
and sine terms for x, y and z in the upper panel. For example, to construct the cardiod:
x = (cos t)(1 - sin t)
y = (sin t)(1 - sin t)
z = 0
using, cos t sin t = (1/2) sin 2t
and, sin2 t = (1/2)(1 - cos 2t)
we get,
x = cos t - 0.5 sin 2t
y = -0.5 + 0.5 cos 2t + sin t
so next to "x cos coeffs" select 1 from the drop down list, enter 1.0 in the text field and click
the "x cos coeffs" button to enter the value, and this has done the "cos t" term. The other four terms
can be done in the same way. (The number, n say, in the drop down list refers to the coefficient
of t, cos nt or sin nt)