how to campute an integral ?

Replies to This Discussion

Permalink Reply by Daniel Piker on November 19, 2010 at 2:34am

Probably, but you'd need to be more specific about what you are integrating.
These might help for starters:
http://en.wikipedia.org/wiki/Integral
http://www.grasshopper3d.com/forum/topics/gh-feature-request-automatic

Permalink Reply by William Lopez Campo on November 19, 2010 at 7:30am

Raminpb,

I am thinking that it's possible, and probably interesting, to go back to the definition of Integral, draw the curve, convert to a surface and extract its area...
Back in the days there were even "graphic" calculations of the Integrals when computers were not to hand.

As Daniel points out, it depends on what you want to integrate.

Kind regards,
William.

Permalink Reply by raminbp on November 19, 2010 at 2:46pm

Dear William

i can't do that, because computing of the integral is an step of curve drawing process . inf act the curve is an Euler elastica and to draw it , you need to solve some equations which are composed of elliptic integrals.

i'm trying to find a way to implement Simpson Quadrature or other numerical integral methods

Regards

Ramin

Permalink Reply by WT4 on November 19, 2010 at 5:04pm

Try the gaussian integration method. This involves sampling the value of the function at specific sampling points.

2 pt sampling, points located at +/- 0.57735 weighting factor=1

3 pt sampling, points located at 0 weighting factor=0.5555, +/- 0.77 weighting factor=0.8888

This requires the integration limits to be between -1 to +1.
If your limits are different, you will need to substitute a new variable to normalise the limits.