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location Munich, Germany
age 35
visits member for 2 years, 2 months
seen 59 mins ago

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


1d
awarded  Nice Answer
2d
comment Why isn't Mathematica plotting my differential equations?
Have you tried evaluating e.g. {x[30.],y[30.}/.sol? This should evaluate to a pair of numbers. If it doesn't, Plot can't work, either.
Apr
14
comment Machine precision infinity
@chuy: $MaxMachineNumber is the largest finite number the machine's native floating point type can represent. But IEEE floating point numbers can also represent plus and minus infinity. I guess he means those.
Apr
12
comment Is it possible to get AltGr key to work in Math.exe?
Happens on my PC too, only in math.exe, not in other console processes. It seems to ignore num-block keys, too, even if num-lock is on. I'd say math.exe is completely unusable (interactively) with a non-us keyboard. Dumb question: Why use the console interface in the first place? Why not use the more comfortable notepad interface?
Apr
11
answered Programming paradigm change
Apr
10
comment Fitting piecewise functions
I think NonlinearModelFit works my minimizing some cost function (e.g. total squared error), but the cost function can't be evaluated if your piecewise function doesn't return a value for some values of x. Have you tried using something like {(a+b)/2,A<x<B} as a fallback? Alternatively, you could come up with your own cost function and just optimize that.
Apr
9
comment Line Intensity Profile From Image
@VitaliyKaurov: I always thought an intensity profile was the sampled intensity values along a path (in this case, a line). Maybe I misunderstood the term. What would be your definition?
Apr
9
answered Line Intensity Profile From Image
Apr
7
awarded  Nice Answer
Mar
28
answered Importation multiple dcm images
Mar
18
awarded  Notable Question
Mar
12
awarded  Good Question
Mar
7
awarded  Guru
Feb
26
comment Correctly set up FindMinimum
I can't try without a sample image, so this is just a guess: Did you try restricting the scfac parameter to ?NumericQ (see here: mathematica.stackexchange.com/questions/18393/…). Also, you should probably Round the size parameter to ImageResize
Feb
20
comment detecting the radius of an incomplete circle
@John: I think AreaRadiusCoverage (for each connected component) takes a disc centered at the centroid, with the same area as the component, and measures the overlap between that disc and the component. For a ring, where all pixels are far from the centroid, this should always be small. Other suitable measurements might be the ConvexCoverage, or maybe something like (MaxCentroidDistance-MinCentroidDistance)/MeanCentroidDistance
Feb
20
revised detecting the radius of an incomplete circle
deleted 1 characters in body
Feb
20
comment detecting the radius of an incomplete circle
@Murta: It's not a duplicate (I think): The answers in that question all use the center of mass of the marked pixels (the centroid). When the circle isn't closed or the "thickness" varies, the center of mass is not the center of the best-fit circle.
Feb
20
answered detecting the radius of an incomplete circle
Feb
4
comment Differentiating a Dot Product
You can even write D[xVec.pVec, {pVec}] to get the gradient wrt pVec, or D[xVec.pVec, {pVec, 2}] to get the Hessian. It took me a long time to figure that out...
Jan
26
awarded  Yearling