On 4/15/2010 12:07 PM, Mark Brooks wrote:
Thanks for your insights and help.
The lines I'm working with will have multiple points. They are hurricane
tracks. The tracks are made of points, about 3-12 hours apart.
Therefore, sometimes the points are close and other times very far away
from each other. I can easily connect the track points to create a line.
But I need the points in between each observation so that I can
determine what county landfall occurs. The y=mx+b method will work, but
I was hoping there may be an easier to do it. Or perhaps I'm making the
problem too complicated to begin with??
Mark
Well thats an interesting problem. I'm not sure how to do it with lines
or points. If you had a line, you could tell if it intersects a polygon
(a county), but then it might intersect many polygons... maybe?
On the other hand if you plot points along the line, checking each time
if you intersect a polygon (a county), would you plug values into x or
y? Increasing or decreasing? If your points are too far apart you
might miss a polygon, but if they are too close together you'll waste a
lot of time processing.
Hum... what if you use a line, find all polygons that intersect that
line, then find the polygon nearest the start point?
On a side note.. aren't hurricane's really wide? Wouldn't several
counties get hit at the same time?
-Andy
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