If you're asking if you can use an equation to drive a spline, thenthe answer is no. You need to use your equation tolocate points on a graph then plot the points in SW. Then youwill have to use the curve through points command.
This would be a great enhancement request.
Try this macro I wrote. It's done well by me.
Thats was really great. I played little with it. Was cool.
Your macro can handle parametric equations very well. But do you have something for implicit (or) explicit equations like
y = f(x) (or) f(x,y)=0.
Now, if i have to use explicit/implicit eqns, first i have to convert them into parametric eqns and then use them which sometimes confuses me
Once again, great job done!!!
Thanks, Ranga. The macro won't automatically handle implicitfunctions of the form f(x,y)=c. It will only plot functions with a1 to 1 mapping in 3D space, i.e. the result of the functionevaluation must be a single point, and no two points can overlap.This boils down to only plotting curves, not surfaces (likef(x,y)=c). Also, no self-intersecting curves. However, if you havea function like x^2 + y^2 = 1, you can easily decompose itparametrically into x=2*t-1, y=sqrt(1-x^2), z=0. This would giveyou half the circle, while y=-sqrt(1-x^2) would plot the otherhalf. Another way would be r=1, th=radians(360)*t, z=0. It would benice if FuncPlot handled implicit functions, but I'm not that gooda programmer and unfortunately don't have that much free time However, keep in mind that Excel function can be used. So if youwanted to create a curve that was C0, but not C1, you could use anIF() command that gave different results for z based on the valuesof x,y,t. Anyhow... have fun.Mahir
If you create a helix with a pitch of 2Pi and a Radius of 1 and then project the profile view of that onto a sketch plane, would that not produce a sine wave?
Now, I don't know how useful it would be, but there it is.
Good observation, John. Assuming SW isn't using some sortof internal spline interpolation, that's a good way to get an exactsinusoidal wave that will remain parametric in case you want tochange it later.
for y = A*cos(k*Theta), 0<=Theta<=L
A = amplitude
k = number of cycles per 2PI radians
L = max angle
The helix parameters should be
profile circle diameter = 2*A
and pitch & revolution
p = 2PI/k
n = L/p
or height and revolution
H = height = L
n = L*k/2PI
or height and pitch
H = L
p = 2PI/k
Hi John & Mahir,
Thanks all, now i able to create to create sine curve . I hope anyway the B-spline approximation done by SW would hold good for a sine curve,