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22150
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location Munich, Germany
age 36
visits member for 2 years, 7 months
seen 1 hour ago

I work at a small mechanical engineering company, where I develop software and image processing algorithms for camera-based inspection machines.


Jun
16
comment How would you efficiently implement BinListsBy?
@Mr.Wizard: I'm trying to, but I honestly don't understand it well enough. To compare the timings, the function should take a function parameter, like the other versions. Yours (I think?) always gathers by the first subelement, which may or may not be faster than calling a user-supplied function.
Jun
15
answered Moment central of a binary image
Jun
11
comment How would you efficiently implement BinListsBy?
@Szabolcs: My actual purpose is to create a "weighted histogram", of e.g. gradient orientations, weighted by gradient strength of every pixel in an image. As in mathematica.stackexchange.com/questions/23602/…. So yes, the data will probably be packed
Jun
11
awarded  Self-Learner
Jun
11
revised How would you efficiently implement BinListsBy?
timing measurements
Jun
11
revised How would you efficiently implement BinListsBy?
typo
Jun
11
answered How would you efficiently implement BinListsBy?
Jun
11
asked How would you efficiently implement BinListsBy?
Jun
6
answered How to count the number of n-gons and line intersections in an image of a complete graph?
Jun
6
answered Exporting pictures in their correct size when using Grid
Jun
2
comment How do I perform the riffle function backward?
Transpose[Partition[{a, b, c, d, e, f}, 2]]
May
30
comment Negative probability?
That's weird: I'm using MMA 9.0.1, Windows, 64bit, and I get \[Pi]^3/840.
May
29
revised Intersecting/Overlapping Image Elements Counts?
added 1899 characters in body
May
29
answered Intersecting/Overlapping Image Elements Counts?
May
20
revised Rebuild a polygon so it doesn't self intersect
added 3 characters in body
May
19
comment Rebuild a polygon so it doesn't self intersect
@Öskå: You're right, I forgot that SortBy treats exact values and machine-precision values differently. Try using N@ArcTan[... or N[pts] instead, then SortBy should sort them properly.
May
19
comment Rebuild a polygon so it doesn't self intersect
It's weird that FindShortestTour doesn't remove intersections as a post-processing step. IIRC, finding&removing intersections is a O(n*log(n)) operation if done right, and it's guaranteed to make the tour shorter.
May
19
revised Rebuild a polygon so it doesn't self intersect
deleted 21 characters in body
May
19
answered Rebuild a polygon so it doesn't self intersect
Apr
28
comment Generating x,y coordinates for an edge detection
@s.s.o: Oops, you're right; I didn't realize there was a shadow. On the other hand, I just answered this question because I didn't notice it was months old (and probably abandoned by the OP). Adding "image processing cleanup code" that will only work for this single image anyway seems kind of pointless now.