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Options for displaying symbolic results?

DaveWooff
5-Regular Member

Options for displaying symbolic results?

Hi,

if I have a polynomial resulting from a symbolic calculation say H(s)--->As^2+Bs+C, is it possible to get Mathcad to display it in the form s^2+(B/A)s+C/A? I'm not sure what the technical term is for this though if someone reminded me I'd probably remember!

Thanks,

D

9 REPLIES 9

Hello!

Maybe this will help:

Expand.jpg

DaveWooff
5-Regular Member
(To:VladimirN)

Thanks for that, I already thought of it but it didn't quite work out nicely and I wondered if there was an "automatic" way to do it. It's not a massive problem, it's just that some common forms of various equations exist in the literature and it would be nice to get the output to match up.

e.g. in electrical filters H(s) = s^2 + 2.wo.s/Q + wo^2.

I've attached a quick example

Many thanks,

D

MikeArmstrong
5-Regular Member
(To:DaveWooff)

I'm sure you'll have to divide both sides of the equation by A, to get the results in the format shown.

Mike

RichardJ
19-Tanzanite
(To:DaveWooff)

if I have a polynomial resulting from a symbolic calculation say H(s)--->As^2+Bs+C, is it possible to get Mathcad to display it in the form s^2+(B/A)s+C/A?

No, because that is not another form of the same polynomial. Normalizing by the first coefficient yields a different polynomial, so you must explicitly do that (as shown by Vladimir).

DaveWooff
5-Regular Member
(To:RichardJ)

Sorry, yes and thanks for correcting me I probably mislead everyone on that point and confused myself in the process. I should have used the following example (in which I wanted to divide throughout by A):

As^2+Bs+C

-----------------

As^2+Ds+E

but I can now see that I was asking a silly question anyway. I apologise for the wasted time and effort.

RichardJ
19-Tanzanite
(To:DaveWooff)

Sorry, yes and thanks for correcting me I probably mislead everyone on that point and confused myself in the process. I should have used the following example (in which I wanted to divide throughout by A):

As^2+Bs+C

-----------------

As^2+Ds+E

You mean like in the attached? It's an ugly way of getting there, but the only one I can think of.

I apologise for the wasted time and effort.

Don't worry about that! Nobody here has any obligation to respond to posts, so if they think it's a waste of time they don't need to respond. And if they think it's waste of time and respond anyway, then they can only point the finger at themselves..

big_grin.gif

DaveWooff
5-Regular Member
(To:RichardJ)

Richard, any chance you could post that in version 2001i or post a jpeg?

Thanks,

David

RichardJ
19-Tanzanite
(To:DaveWooff)

I didn't realize you had 2001i. Here's what it looks like in MC15:

rewrite poly.gif

It won't work in 2001i though, because you don't have the numer and denom functions. Those functions exist in MC11, but the final expression is simplified so it doesn't work anyway. In MC12 and 13 they removed the numer and denom functions because they were only in MC11 by mistake, so it doesn't work in those versions either (in MC14, when they switched the symbolic engine to MuPad, they put them back in).

DaveWooff
5-Regular Member
(To:RichardJ)

Thank you.

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