- #1
xyz3003
- 5
- 0
I think I have returned all my math back to teachers without any refund.
y=f(x);
h=xb-xa, which is very small.
My Q is to calculate curve length rather than area numerically.
But let me use area as example to show you what i want.
to calculate area between xa to xb, we have 2 ways:
1) area=(f(xa)+f(xb))*h/2; (trapezoid?)
2) area=(f(xa)+4*f(xm)+f(xb))*h/6; here xm=(xa+xb)/2; (parabola?)
As my test, second one is much better than first.
for curve length:
1) len=square root( (f(xb)-f(xa))*(f(xb)-f(xa)) + h*h);
actually, it is distance from (xa, f(xa)) to (xb, f(xb)).
do you know second way to calculate curve length as in area sample above, simple, easy-to-use and better?
any links or explanations are highly appreciated.
thanks.
.
.
y=f(x);
h=xb-xa, which is very small.
My Q is to calculate curve length rather than area numerically.
But let me use area as example to show you what i want.
to calculate area between xa to xb, we have 2 ways:
1) area=(f(xa)+f(xb))*h/2; (trapezoid?)
2) area=(f(xa)+4*f(xm)+f(xb))*h/6; here xm=(xa+xb)/2; (parabola?)
As my test, second one is much better than first.
for curve length:
1) len=square root( (f(xb)-f(xa))*(f(xb)-f(xa)) + h*h);
actually, it is distance from (xa, f(xa)) to (xb, f(xb)).
do you know second way to calculate curve length as in area sample above, simple, easy-to-use and better?
any links or explanations are highly appreciated.
thanks.
.
.