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honeycomb decay

Mathematica can save time delays between frames together with animated GIF (look for "DisplayDurations" under options of GIF format). This in turn allowed me to produce exactly 28 frames for the decay of this honeycomb with 28 cells. Modelling radioactive decay, where for example time intervals between clicks on a Geiger counter are approximately exponentially distributed, I can simulate the delays (rounded and shifted to run from t1/100-th seconds with average value (t1+t0)/100-th seconds) as:

delays[{t1_, t0_}, n_] :=
 t1 + Round[
   RandomVariate[ExponentialDistribution[1/t0], n]]

I set t1=2 here. Most browser can't present a delay of 2/100-th seconds properly. Chrome can.


Oct
4
answered Position of First nonzero number
Jul
31
accepted FindRoot equation-variable mismatch
Jul
18
comment FindRoot equation-variable mismatch
I'm using a bisection routine now. I'd rather use FindRoot for elegance and accuracy.
Jul
18
asked FindRoot equation-variable mismatch
Jun
11
awarded  Nice Question
Jun
11
comment How do I find the intersection of a closed 3D curve given by numerical data with a specified plane?
Why do you sample over such a broad interval? -Pi to Pi would suffice.
Jun
10
awarded  Nice Answer
Jun
9
answered A function that accepts a pair or a list of pairs
Jun
9
answered Finding y given x from an interpolating function
Jun
8
answered Wrapping a function in count
Jun
8
comment How to find major color in a picture?
@Guillochon Along this lines. Help notes on the function: The returned colors are ordered based on the size of the clusters they represent. The specifics of clustering I don't know, it could be something cleverer than euclidean distance.
Jun
4
comment How do I find the coordinates of points in this image?
@cormullion I agree, should distance 2 not exclude certain original dot.
Jun
4
comment How do I find the coordinates of points in this image?
PixelValuePositions[Thinning@ColorNegate@ImageCrop@Binarize@image, 1] perhaps.
Jun
4
comment How do I find the coordinates of points in this image?
Are there really two thousand points in the original image (length of pts above)?
Jun
2
comment Solving differential equations with constraints
@KamovSergey If the constraints form a pattern of some sort you can encode you might want to look how to automate equations (WhenEvent is part of equation). You can do that. See help on WhenEvent, then Applications > Bouncing Balls. Or you could MapThread over the specification matrix. It shouldn't be hard to set up the whole problem elegantly I think.
Jun
2
awarded  Organizer
Jun
2
revised Solving differential equations with constraints
edited tags
Jun
2
comment Solving differential equations with constraints
I did something for x[t], try and stretch that to x'[t].
Jun
2
answered Solving differential equations with constraints
Jun
2
comment Solving differential equations with constraints
It's doing what it's specified to my understanding. Do you want the variables to remain at boundaries until force changes direction? Do you want perhaps the force to change direction upon hitting constraints? In that case you must introduce force as additional (discrete) variable in the equations of NDSolve.