Beefy Boxes and Bandwidth Generously Provided by pair Networks
Perl: the Markov chain saw

Re^3: Speeding up point-in-polygon

by explorer (Chaplain)
on Jul 24, 2006 at 10:39 UTC ( #563231=note: print w/ replies, xml ) Need Help??

in reply to Re^2: Speeding up point-in-polygon
in thread Speeding up point-in-polygon

If you can reduce the data to cartesian coords. and the entire zone can reside into RAM, PDL is the faster solution.

Example: If $zone is a piddle of bytes with an 1 where the point's coords, you can retrieve the coords of points into polygon's box limits with:
$area = $zone->slice("$xmin:$xmax,$ymin:$ymax"); $coord_points = wichND( $area );
Now, you will have the coords of all points into the $area:
@x_coords = list $coord_points->slice("(0),:"); @y_coords = list $coord_points->slice("(1),:");
This is the fast clipping method if you can reduce the data universe to cartesian coords.

And PDL is a C compiled library.
Comment on Re^3: Speeding up point-in-polygon
Select or Download Code

Log In?

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://563231]
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others rifling through the Monastery: (5)
As of 2016-05-28 00:12 GMT
Find Nodes?
    Voting Booth?