/sci/ - Science & Math » Thread #11088562

85KiB, 290x267, countourLines.png

View Same Google iqdb SauceNAO

Contour lines - math generated

Anonymous Thu 24 Oct 20:58:33 2019 No.11088562 View Reply Original Report

Quoted By: >>11088597 >>11088621 >>11090532

Hey /sci/
I am looking for algos/method for generating isoline/contour lines from set of irregulary placed points (x, y - cords, z - values).

I know with kriging it would be pretty easy to generate grid of points
I could do it with delanuay triangulation

but is there more?
I feel like I am missing something

Anonymous

Anonymous Thu 24 Oct 2019 21:13:27 No.11088597 Report

Quoted By:

>>11088562
contour(X,Y,Z)

Anonymous

Anonymous Thu 24 Oct 2019 21:26:26 No.11088621 Report

Quoted By: >>11089045

>>11088562
place the points in a hash map with the key being the z-coordinate and map being a list of points, then go through each key and use your choice of convex hull algorithm to draw the polygon formed by the points in that contour line.

Anonymous

Anonymous Fri 25 Oct 2019 00:39:43 No.11089045 Report

Quoted By:

>>11088621
>convex hull algorithm
thx

Anonymous

Anonymous Fri 25 Oct 2019 16:29:37 No.11090532 Report

Quoted By:

>>11088562
You are talking about spatial interpolation. Kriging is one of the more advanced techniques, so you are obviously on the right lines. Spatial interpolation is basically educated guesswork, because there is no technique that will always give perfect results when compared to reality, and also some techniques will give dreadful results on one dataset versus great results on another. And then with each technique you can often vary the input parameters. So it's really a case of generating a range of outputs using different inputs to different algorithms, and then comparing them and using your judgement to select the one that looks best using human intuition.

Taking kriging for example - which was developed in South Africa for use in estimating good areas for gold prospecting - you can probably imagine that someone with knowledge of the geology and years of experience with kriging would come to know intuitively what looks like a plausible output.

That's probably more than you wanted to know (I have a degree in spatial science).

Capcode	All Only User Posts Only Moderator Posts Only Admin Posts Only Developer Posts
Show Posts	All Only With Images Only Without Images
Deleted Posts	All Only Deleted Posts Only Non-Deleted Posts
Ghost Posts	All Only Ghost Posts Only Non-Ghost Posts
Post Type	All Only Sticky Threads Only Opening Posts Only Reply Posts
Results	All Grouped By Threads
Order	Latest Posts First Oldest Posts First

Your latest searches