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Is it my own or Mathcad 15 error?

ValeryOchkov
24-Ruby IV

Is it my own or Mathcad 15 error?

When I have 20 elements in vectors with operators (for parallel calculation of 4 curves) all is OK!

When I have 40 elements in vectors with operators (for parallel calculation of 8 curves) it is not OK!

See please attach!

My Mathcad Prime 4 is break when I open the converted 8-Flyers file!

Help please

 

ACCEPTED SOLUTION

Accepted Solutions

One mathematics teacher (a women!) from the Air Force Academy found a mistake in my model!

See please the attach!

Tetr-Bats.gif

 

View solution in original post

43 REPLIES 43

Disable the global assignment of 500 to FRAME before you begin the animation and both the 4- and 8-flyers work ok. (The MC15 ones that is;  I don't know about the Prime file).

 

Alan

I dont't experience any errors when I open your 8-flyer files.

Both the Mathcad 15 and the Prime file seem to work OK and show the plots.

Can you be more specific about what is not OK and what is broken?

Here is what I see in MC15

B1.png

and here is P5

B2.png

Thanks Alan and Werner!

8 bats fly out of cube tops. They fly in pairs against each other 1->2, 2->6, 6->7, 7->3, 3->4, 4->8, 8->5 and 5-1 (see the picture). The model with 4 bats works without errors. In the Model with 8 bats - the wrong answer. This is my mistake or mistake Mathcad. May be Mathcad can work with 20 operators in the vector and cannon works with 40 ones!

cube.png

Still not clear to me what you think that is going wrong.

May be the picture tells about the error!

4-correct-4-non-correct.png


@ValeryOchkov wrote:

May be the picture tells about the error!

 


Yes, I see the problem now. Haven't checked if its your setup or if its Mathcad doing something wrong. Your converted sheet shows the very same result in Prime 5.

I have a plan to go from 4 points to 5, 6, 7 and 8 points and fixed an error.

I think it is an error in parallel calculation of Mathcad 15 and Prime!

I will try the for loop!

How about as in the following Valery?

 

Unable to play video. Please try again later.
(view in My Videos)

Thanks, Alan!

8-Flyer-R.gif

8-Flyer-R-ZX.gif

8-Flyer-R-YX.gif

8-Flyer-R-ZY.gif

In my previous file the points did not travel at constant speed. Instead, they moved a constant fraction of the distance from their targets each time-step.  In the attached file the points move with constant speed.

 

Alan

  

Thanks Alan!

See animations! Is it correct - not square and the meeting not in the center of the cube?

8-Flyer-R1.gif8-Flyer-R-YX1.gif

The final position being off-centre results from your initial target positions.  You have two points that start chasing targets on vertices along diagonals (in the x-z plane), while all the other points start chasing targets at adjacent vertices along edges.  If you start with a a more symmetrical arrangement (such as all points chasing targets on adjacent edges) you end up with a central final arrangement.

 

Alan


@AlanStevens wrote:

If you start with a a more symmetrical arrangement (such as all points chasing targets on adjacent edges) you end up with a central final arrangement.

 

Alan


But it is possible only with 2D problem (a square) and not possible with 3D one (a cube) Smiley Sad

Or?

Simply exchange the start coordinates of points 5 and 8 and also of points 6 and 7 to achieve a better symmetry.

A real perfect symmetry would not be possible using all 8 vertices of the cube.

You may consider using the 6 centre points of the side surface squares of the cube (vertices of a regular octahedron).

B.png

Thanks, Werner!

But where is animation (2 and 3D) with green lines and/or Mathcad 15 sheet?


@ValeryOchkov wrote:

Thanks, Werner!

But where is animation (2 and 3D) with green lines and/or Mathcad 15 sheet?


The sheet is already deleted - it was the sheet Alan posted and I just exchanged the two pairs of points as explained above.

Concerning animations - after a while they a getting a little bit boring 😉


@Werner_E wrote:

@ValeryOchkov wrote:

Thanks, Werner!

But where is animation (2 and 3D) with green lines and/or Mathcad 15 sheet?


The sheet is already deleted - it was the sheet Alan posted and I just exchanged the two pairs of points as explained above.

 


Do please this one more - download Alan's sheet, exchanged the two pairs of points and... put it here!

Here you are

 

Thanks, Werner!

8-Flyer-W.gif

8-Flyer-W-ZX.gif

8-Flyer-W-YX.gif

Not an animation but 3 views of 3D picture:

8-Flyer-3-View.png 

But the question is still left!

Is it my own or Mathcad 15 error?

Tetr-Flyer.gifTetr-Flyer-ZX.gifTetr-Flyer-YX.gifTetr-Flyer-ZY.gif

 

I guess its not Mathcad but the way you had setup the problem.

There sure should no points go outside the tetrahedron.

I digged into my archive and found an old sheet were I played around with a similar "problem" and quickly adapted it to your scenarios. Here's what I see:

TetraAni.gif

Thanks, Werner!

And send please the Mathcad sheet!

 

ps

One legendary soviet milk packing

milk.png 


@ValeryOchkov wrote:

Thanks, Werner!

And send please the Mathcad sheet!


It won't help finding the error in yours as it uses a completely different approach compared to the one in your sheet.

But maybe I'll clean up he sheet an post it later anyway.

I am waiting for...

And what about this

Tert-etc.png

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