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ptc-17160021-Visitor
1-Visitor
February 16, 2010
Question

inverse transform returns 'variable undefined

  • February 16, 2010
  • 1 reply
  • 5549 views
Attempting to perform an inverse Laplace transform
on a simple 2nd order polynomial (2 poles, 1 zero)

The symbolic operation works, but when I attempt to
assign the result to a function, Mathcad 12.1 always
returns "This variable is undefined".

Suggestions anyone?

1 reply

R
RichardJ19-Tanzanite
19-Tanzanite
February 16, 2010
It appears to be a bug in version 12. It works fine in versions 11, 13 and 14. I can't actually check it in version 12 though because it's such a lemon version of Mathcad last time I changed PC I couldn't be bothered to install it along with all the others. Perhaps someone else that has version 12 installed can check.

Richard
A
AlvaroDíaz12-Amethyst
12-Amethyst
February 17, 2010
On 2/16/2010 3:57:16 PM, rijackson wrote:
>It appears to be a bug in version 12.

Without version 12 I guess that the bug is in the t variable: try to add ",t" in the inverse laplace. Also, write t:=t after t:=0.

If not, must to manual assign the impulse function by copy & paste.

Regards. Alvaro.
M
mzeftel1-Visitor
1-Visitor
February 17, 2010
I recommend that you upgrade to Mathcad 14, which you can do for only $99 including all extension packs and libraries at http://www.ptc.com/go/mathcad99.

Mona
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