topic Re: Matrix issue PTC Mathcad 10.0.1.0 in Mathcad

Matrix issue PTC Mathcad 10.0.1.0

MW_1302355 — Wed, 12 Feb 2025 22:33:27 GMT

Sorry, I don't know how to get the Vadl value? Could anyone help me please?

Re: Matrix issue PTC Mathcad 10.0.1.0

ttokoro — Wed, 12 Feb 2025 23:32:16 GMT

Re: Matrix issue PTC Mathcad 10.0.1.0

MW_1302355 — Wed, 12 Feb 2025 23:57:58 GMT

Thank you so much for your help.

Re: Matrix issue PTC Mathcad 10.0.1.0

MW_1302355 — Thu, 13 Feb 2025 00:12:53 GMT

Awesome! It make perfect sense.

Thank you for your help.

~~~~~~~~~~~~~~~
Md. Wahiduzzaman
Bengal Engineering, Inc.

Re: Matrix issue PTC Mathcad 10.0.1.0

SPaulis — Thu, 13 Feb 2025 00:15:10 GMT

Also consider that you defined "i" as a range value and not an array. A simple way to do it is define "i" as a range of numbers defining the indices of the elements of an array, then do the math to define each element (also using "i"). Alpha is just the rate that you want each calculation to increase by

Re: Matrix issue PTC Mathcad 10.0.1.0

MW_1302355 — Thu, 13 Feb 2025 00:56:53 GMT

Thank you so much!

~~~~~~~~~~~~~~~
Md. Wahiduzzaman
Bengal Engineering, Inc.

Re: Matrix issue PTC Mathcad 10.0.1.0

Werner_E — Thu, 13 Feb 2025 03:47:28 GMT

OK, in the meantime you already know that the problem was that you defined x as a range and not as a vector.

Instead of using an extra variable i to index the vector to create or to use a utility function to turn a range into a vector, you could also use a utility function which created the vector right ahead - similar to a range definition by providing the first, second and end value.

Furthermore it makes not much sense to me that you strip the unit feet when defining the range/vector "x" just to add the unit again when using "x" in the definition of V.ADL. You don't have to strip the units when defining a range or a vector.

In case of this simply calculation it would not have been necessary to use vectorization (the arrow over the expression). But its good style and I would suggest to always use it when applying a scalar calculation to vector arguments.

If D would be a vector as well, vectorization would be absolutely necessary as otherwise the multiplication would be done as dot-product (scalar product) and the result so would be a single value and not a vector with 6 values.

BTW, what you did - following the definition of the range immediately by an evaluation (the = sign at the end) - automatically turned the range into a vector in older Prime versions. So what you did would work without problems in versions of Prime up to P9. Prime 10 is the first version where this undocumented trick does not work anymore. That's the reason you have to resort to other methods to define x as a vector. Three methods to do so where shown in this thread. PTC promised to provide a easier built-in way (either to turn a range into a vector or to create a vector similar to a range, I don't know) in Prime 11.

Prime 10 sheet attached

Re: Matrix issue PTC Mathcad 10.0.1.0

LucMeekes — Thu, 13 Feb 2025 07:33:25 GMT

I think it's a serious BUG.

If, with the definitions of L and DLsw as given, this is allowed:

Then this should be equally allowed:

There was no such problem with Mathcad (11):

Success!
Luc

Re: Matrix issue PTC Mathcad 10.0.1.0

Werner_E — Thu, 13 Feb 2025 12:08:26 GMT

There was no such problem with Mathcad (11):

Are you sure? In your last picture of MC11 you did not try to assign the expression to a variable V.ADL !

The main difference and cause of the problem is this attempt to assign the 'calculation' to a variable!
And as far as I remember it was the very same in real Mathcad, too. At least it is in Mathcad 15:

Its a mis-use of a range variable. The bug, if we want to call it such, is that Mathcad allows the evaluation of an expression like 2*r with r being a range without throwing that very error, not that it refuses the assignment to a variable.

A range is kind of an implicit loop and and an expression using a range seems to be kind of an invalid object (so it can't be assigned a variable) but still can be displayed on its own without an error (which sometimes may be convenient).

So the behaviour in Prime is the very same as its in Mathcad(15)

Re: Matrix issue PTC Mathcad 10.0.1.0

MW_1302355 — Thu, 13 Feb 2025 16:42:53 GMT

Good morning, Folks,

It is amazing to see all the Titan’s are into thoughtful discussions. All I remember, it was not giving this error in Mathcad 15. Perhaps, the code writers were trying to solve problems that I am not aware of.

I must say that PTC Community is vibrant and essential for users like me.

Thank you!

~~~~~~~~~~~~~~~
Md. Wahiduzzaman
Bengal Engineering, Inc.

Re: Matrix issue PTC Mathcad 10.0.1.0

LucMeekes — Thu, 13 Feb 2025 16:55:43 GMT

I'm afraid you're right (again!).

Luc

Re: Matrix issue PTC Mathcad 10.0.1.0

Werner_E — Thu, 13 Feb 2025 19:06:30 GMT

@MW_1302355 wrote:

Good morning, Folks,

It is amazing to see all the Titan’s are into thoughtful discussions. All I remember, it was not giving this error in Mathcad 15.

Correct! I already explained that. Writing an equal sign right after the definition, as you did, turned the range into a vector. This undocumented convenient trick worked in Prime, too, but only up to version 9. In version 10 it was broken on purpose as it admittedly was illogic that an evaluation should change the data type.

I can understand this decision, but it would have made sense to provide at the same time an alternative “legal” way of either converting a range into a vector and/or creating a vector based on its first two values and its final value.

We will have to wait and see how useful the alternatives announced for Prime 11 will be.

Re: Matrix issue PTC Mathcad 10.0.1.0

anursingh — Tue, 11 Mar 2025 19:54:08 GMT

Hi @MW_1302355,

I wanted to see if you got the help you needed.

If so, please mark the appropriate reply as the Accepted Solution. It will help other members who may have the same question.
Please note that industry experts also review the replies and may eventually accept one of them as solution on your behalf.
Of course, if you have more to share on your issue, please pursue the conversation.

Thanks,
Anurag