a_simsim

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Dear Community,

Maple has the fancy VoronoiDiagram command, which generates Voronoi grids from a set of 2D distributed points. Does somebody know how the cornerpoint coordinates of the individual Voronoi cells  of the obtained Voronoi grid can be exported as a list of (xi, yi)  coordinate pairs? Could you possibly give a simple example?

Tx in advance, best regards

Andras

 

 

Dear Community,

I have a four compartment flow model described with the following system of linear ODEs:

diff(L[1](t), t) = L[2](t)/T[21] - L[1](t)/T[12]

diff(L[2](t), t) = L[1](t)/T[12] - L[2](t)/T[21] + L[3](t)/T[32] - L[2](t)/T[23] + Q(t)

diff(L[3](t), t) = L[2](t)/T[23] - L[3](t)/T[32] + L[4](t)/T[43] - L[3](t)/T[34]

diff(L[4](t), t) = L[3](t)/T[34] - L[4](t)/T[43]

(For easier readability I’ve also described the problem in the attached FourCompartmentModelDescription.docx Word file.)

 

The time constants are as follows:

T12 = 23.1481 d

T21 = 5.4537 d

T23 =  9.752 d

T32 = 14.9007 d

T34 = 8.8235 d

T43 = 363.7255 d

Initial conditions are as follows:

L1(0) = 2500.

L2(0) = 589.

L3(0) = 900.

L4(0) = 37100.

Simulation should run from 0 to 400 d.

Could you pls. help me, to solve it numerically in Maple? As a solution I would need L1(t), L2(t), L3(t) and L4(t) both numerically and graphically. I used Maple to solve ODEs previously, but this time I don’t know, how to correctly specify the problem with an external, tabulated source. I’ve also prepared and attached a Maple worksheet, but did not try to run it yet. (FourCompartments.mw). The external Q(t) source for compartment 2 is attached as Source.xlsx. Should I've forgotten something, pls. let me know.

Your kind help is appreciated in advance,

best regards

Andras

 

MaplePrimesFourCompartmentModelDescription.docx

FourCompartments.mw

Source.xlsx

Dear Community,

I would like to have an inverse interpolation with a 2D lookup table in MapleSim. The usual 2D lookup interpolation has u1 column values, and u2 row values, and a corresponding   y   table values, i.e. y = f(u1,u2). Now I would like to go the reverse way. Suppose I know y, and u2, and I would like to get u1. How can I implement this in MapleSim? An additional information is, that the 3D surface represented by the f(u1, u2) function is a smooth, slightly curved, monotonically sloping surface, so to any  y  value a unique pair of u1 and u2 values belong.

 

With my specific data, which are attached in the TestVLP.xlsx file:

 

  • u2 values are: 1st row, cells 2 .. 14
  • u1 values are  1st column, rows 2 .. 11
  • tabulated values are all the rest, i.e. from cell(2,2) .. cell(11,14)

 

Now for my case:

 

  • u2 = 42000.0
  • y   = 94.5614

 

How much is u1? I know the correct answer from elsewhere, it should be something very close to u1 ~ 85. This  y  value is in the rectangle bordered by columns 7 .. 8  and rows 5 .. 6 in the Excel file.

 

So my question is how do I correctly implement this in MapleSim? As visible from the attached TestInverse2DInterpolation.msim file I tried to do it with an Inverse Block Constraints component and a horizontally flipped 2D Lookup Table (VLP) and Constants for y and u2, but upon running MapleSim I get an error message that no solution is found, although the solution is relatively easy and straightforward. May I ask you to have a look at it, what can be the problem here, what do I do wrong? I’m using MapleSim 2019.2.

 

Your kind help is appreciated in advance

best regards

 

Andras

TestInverse2DInterpolation.msim

TestVLP.xlsx

Dear Community,

I have a simulation in MapleSim, and I have a probe in the system, for which measured data are also available. How can I load these measured data into MapleSim and compare them to the calculated results (probe data) visually? (Preferably in the "Analysis Window: Simulation Results" which pops up by pressing F6)

Tx for the kind help in advance,

best regards,

Andras

 

Dear Community,

I would like to evaluate this difficult function:  

Unfortunately when I try to define it in Maple, I always get an error message. I tried it in many different ways, but always failed. See also the attached workbook. Can someone pls. have a look, what I do wrong?

Tx for your kind help in advance,

best regards

Andras

DifficultFunction.mw

 

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