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


Dec
7
comment Count Elements in Image
If you just want information about the components (centroid, caliper length), ComponentMeasurements should be more useful than SelectComponents
Dec
7
revised What is ImageDistance measuring?
added 605 characters in body
Dec
7
answered What is ImageDistance measuring?
Dec
7
comment Use of own unit abbreviations
So I'm not the only one who did that (mathematica.stackexchange.com/questions/15338/…). But you need some workarounds to make it work if some values can become 0.
Dec
4
revised Simpler input for the new unit support
added 93 characters in body
Dec
3
comment What is Mathematica's equivalent to MATLAB's Simulink?
I've heard of SystemModeler, but didn't have time to download a demo and play with it. For me (and others, I think) this answer could be improved a lot by showing one or more simple problems and how they would be tackled with Simulink and SystemModeler.
Dec
3
comment The correct way to linearize colorspace before resizing, blurring etc
I've tested this with (industrial) cameras, grayvalues were practically linear. So this is probably not a property of the color space, but of the camera type and analog/digital preprocessing done in the camera. But if it isn't linear - why not just use ImageApply before resizing?
Dec
1
accepted Should 0 * 5ft be 0 or 0ft?
Dec
1
accepted Simpler input for the new unit support
Dec
1
revised Simpler input for the new unit support
added 709 characters in body
Nov
30
comment Version 9 Blue Screen or Self-Test Error on Windows 7 64-bit
Great! Your answer worked on my machine, too. No more bluescreens when I enter [esc]pw[esc]!
Nov
30
comment Version 9 Blue Screen or Self-Test Error on Windows 7 64-bit
+1. I have a similar problem, only my machine bluescreens when Mathematica tries to render the piecewise symbol, or when I open the fonts control panel folder. I "fixed" it by removing the Mathematica5.ttf font. I thought this was a bug in my video driver, but maybe something's wrong with this ttf file.
Nov
29
awarded  Nice Question
Nov
29
awarded  Nice Question
Nov
29
comment Should 0 * 5ft be 0 or 0ft?
+1, this looks very promising. But wouldn't it make more sense to tag the assignment to Quantity instead of Times? Then ordinary multiplications not involving quantities wouldn't be slower or behave differently, right? I've tried Quantity /: (0 | 0.) Quantity[_, unit_] := Quantity[0, unit] and it seems to work just as well.
Nov
29
comment Should 0 * 5ft be 0 or 0ft?
There would be two ways to fix this: Either make sure that Times[0, Quantity] doesn't simplify to 0, or make sure that Quantity and UnitConvert treat 0 as a value that can have any dimension. That would have been possible without changing the whole core. That's how the old Units package and AutomaticUnits apparently solved the same problem.
Nov
29
comment Should 0 * 5ft be 0 or 0ft?
0 times almost anything in Mathematica gives 0. That's exactly the problem. If any dimensionless subexpression becomes 0, Mathematica will throw away all the units and further calculations might fail (although they won't always fail, as you demonstrated).
Nov
29
comment Should 0 * 5ft be 0 or 0ft?
(I think) Rationalizing 0. to 0 works because 0 + _ is automatically simplified to _, but 0. + _ is not. the bug is still there, it's just masked in this special case.
Nov
29
comment Should 0 * 5ft be 0 or 0ft?
@swish: Seems as if AutomaticUnits doesn't work in version 9 any more... I'll probably keep using the built-in Units package
Nov
29
comment Should 0 * 5ft be 0 or 0ft?
Only in this special case. Take UnitConvert[a * startPoint, "Inches"] instead - this will not work for 0 or 0.