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The first two challenges were biased towards mechanical engineering. May’s challenge pertains to geometry.

Create a worksheet in which you calculate (1) the diameter of a circle and (2) the length of a side of a square that yields the minimum combined area for a combined perimeter of 1 meter.

This is an optimization problem. What tools within Mathcad can provide you with a result?

Optional: How can you depict the results? Can you use a 2D plot or Chart Component to visualize the answer?

Find the Mathcad Community Challenge Guidelines here!

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May 04, 2022
05:35 PM

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May 04, 2022
05:35 PM

May 14, 2022
12:44 PM

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May 14, 2022
12:44 PM

Good solution. But it won't run in Express (no symbolics, no polyroots)

May 16, 2022
09:48 AM

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May 16, 2022
09:48 AM

@Fred_Kohlhepp wrote:

Good solution. But it won't run in Express (no symbolics, no polyroots)

Also "Minimize" (even without a solve block) is a premium function.

But the derivative operator and the "root" function are not and you can use them for a solution in Express. You just have to manually solve a simple equation 😉

May 16, 2022
10:44 AM

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May 16, 2022
10:44 AM

Using a more powerful software you may even visualize by creating an animation 😉

May 16, 2022
06:57 PM

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May 16, 2022
06:57 PM

May 16, 2022
07:14 PM

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May 16, 2022
07:14 PM

Bit of labelling would be helpful. This is like a flaming Homer.

But Short and simple.

Attach file please.

May 16, 2022
07:29 PM

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May 16, 2022
07:29 PM

@ppal wrote:

Bit of labelling would be helpful. This is like a flaming Homer.

But Short and simple.

Attach file please.

Moe is using real Mathcad and this seems to be a Prime only challenge. Nonetheless I would vote for his solution being the winner.

BTW, because Moe's nice compact solution is using Lagrange and the Nabla operator - is the Nabla operator now finally available in Prime 8 or is it still missing?

We could make Moe's solution even a bit more compact by using the symbolic "solve" instead of evaluating the solve block symbolically (which is something not allowed to do in Prime anyway).

It could even be made a one-liner (but I wouldn't suggest doing so):

If the Nabla operator still is not available in Prime, you would have to do it the hard way

As usual Primes infamous auto-labeling bug required to manually re-label some variables to make it work.

I seem to remember to have read that PTC planned to implement a partial derivative operator. While being only an optical display thing it would be appreciated. Is it already implemented in Prime 8 or was I just reading the roadmap for future versions?

May 16, 2022
07:58 PM

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May 16, 2022
07:58 PM

May 16, 2022
08:21 PM

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May 16, 2022
08:21 PM

Thats disappointing! (I assume the pic is from Prime8 )

And how about the partial derivative operator?

May 16, 2022
08:31 PM

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May 16, 2022
08:31 PM

Yes, sorry, but as Werner indicates, I am using Mathcad 15. I remain firmly in the camp of "I'll switch to Prime when it can do everything 15 can do".

Very nice Flaming Homer reference, btw.

May 16, 2022
08:43 PM

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May 16, 2022
08:43 PM

@MoeSzyslak wrote:

"I'll switch to Prime when it can do everything 15 can do".

Never?

May 16, 2022
09:19 PM

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May 16, 2022
09:19 PM

Hi

MATHCAD 15

Converted to Prime 8

May 17, 2022
06:54 AM

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May 17, 2022
06:54 AM

I knew that the "grad" operator was available in the original Mathcad, but I haven't seen it in Prime. Yet you show it in the Prime solve block, with a message that it isn't available.

So how did Prime execute the solve block?

May 17, 2022
05:18 PM

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May 17, 2022
05:18 PM

It didn't - its lying and cheating

This is what it really does when you ask it to recalculate:

May 18, 2022
08:38 AM

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May 18, 2022
08:38 AM

So how did Prime execute the solve block?

The converter simply inserted a picture of the Mathcad 15 region.

Prime did not execute the solve block. As usual for Prime it stores the results of the last calculation within its file and displays them when you open a file. The file is not recalculated automatically when you open a file (as is the case in MC15 with auto-calc on). So the result you see is the result of the last calculation done in MC15 by the converter.

This is also the reason you can use Prime Express as a reader for Prime files which use premium functions. You see what the sheet looked like in full Prime but when you try to recalculate, the premium functions will fail.

So see in ppal's answer that the recalculation in Prime yields just "Find(...)". Actually its an empty solve block without any constraint and as we know Prime won't allow to evaluate a solve block symbolically.

May 23, 2022
02:10 AM

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May 23, 2022
02:10 AM

May 23, 2022
05:37 PM

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May 23, 2022
05:37 PM

I opened in mathcad 15

Get errors:

May 24, 2022
07:59 AM

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May 24, 2022
07:59 AM

This worksheet from **11**th version of regular Mathcad.

May 24, 2022
08:00 AM

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May 24, 2022
08:00 AM

With animation!

Jun 01, 2022
10:36 AM

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Jun 01, 2022
10:36 AM

Thanks to everyone for your contributions; Dave will be reviewing them in short order since May is now over. I'm hoping for some good discussion and learnings to come out of it!

(Badges will also come soon.)

Jun 09, 2022
10:47 AM

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Jun 09, 2022
10:47 AM

No June Challenge??

Jun 09, 2022
10:53 AM

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Jun 09, 2022
10:53 AM

It's bimonthly, so there's been a January, March, and May challenge... and next there'll be a July.

Jun 13, 2022
09:50 AM

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Jun 13, 2022
09:50 AM

Badges have been distributed to valid entrants; Dave's blog on the challenge has also been published to Mathcad.com: https://www.mathcad.com/en/blogs/community-challenge-isoperimetric-problem

Great job!

Jun 14, 2022
05:14 PM

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Jun 14, 2022
05:14 PM

So, it seems that my entry was not "valid" because it required Mathcad 15. Alas.

Jun 15, 2022
09:27 AM

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Jun 15, 2022
09:27 AM

The last bullet point of the guidelines thread says as much that it's a Prime-based challenge.

Jun 20, 2022
11:14 AM

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Jun 20, 2022
11:14 AM