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Geminist Geminist is offline
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Default Intersection between a line and multiple semi circle curve

Hi Andy,

The irregular line is the same with the line shown in your website.

I have made a crude sketch here which may be of help.

http://img217.imageshack.us/img217/6937/untitled3tb.jpg

The radius/coordinaate of the semi circle will always remain the same
throughout. The semi circle will never go lower than -ve Y axis. Which
means is starts on the -ve side of X axis and terminates at +ve side of the X
axis, forming a 180 deg semi circle.

What I am trying to do is, the user will put in coordinates to draw the
irregular line while the semi circle will remain unchanged. Excel will then
find out all the coordinates where the line intersects with any of the semi
circle.

The semi circle will always be centered in the point of origin on the axis.

Hopefully this helps, thanks again.

"Andy Pope" wrote:

Hi,

What information do you have about the curve? Radius, diameter, start
angle, finish angle etc?
And what is an irregular line?

I don't yet know the math required to calculate intersections between
curves and lines but google can help with that. It should then be a case
of creating formula and or VBA code.

Cheers
Andy

Geminist wrote:
Hi there,

I have a few (approximately 5) semi circle curve and an irregular line that
cuts across these curves.

I am trying to find the points (x,y) where this line intersects with the
curves. This means that whenever the line intersects on any of the curves, a
point (x,y) where the line and the curves intersects will be returned.

http://www.andypope.info/charts/intersection.htm

I had a look on the above website and it does show that you can achieve this
with excel. My problem is, I'm dealing with a few curves and not just two
lines.

If this helps, the curve will always have the same coordinate (it will
always be the same shape at the same points). Only the irregular line will
change as this is what the user input.

I'm still looking around for an answer and I'm sure someone here will be
able to help me with my problem.

Thank you very much.


--

Andy Pope, Microsoft MVP - Excel
http://www.andypope.info