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1-Visitor
February 17, 2010
Question

numerical inverse laplace fails

  • February 17, 2010
  • 1 reply
  • 2850 views
Want to perform a numerical inverse laplace
transform on a polynomial.

Version 12 returns "no symbolic result found".

Colleague ran the file through Version 14 -
returns "Expecting an arithmetical expression"

Colleague also ran the file through Version 11 -
things calculate beautifully.

Anyone have suggestions? Ideas to get a numerical
solution in V12?


Hint: if you manually re-assign the poly values
rather than reading them from a file (as shown on
the 2nd page), the thing will calculate in V12.

Manually re-assigning things at every calculation
isn't an acceptable answer...

1 reply

1-Visitor
February 17, 2010
No idea about MC12 (that's a particularly buggy version). But in MC14 the problem is that the READPRN is not being properly evaluated by the symbolic processor, but is being left as an unevaluated expression. You can work around this by using the combined assign/display, which uses the numeric results as the symbolic value.

Your vectorizations are incorrect and meaningless. You cannot vectorize the subscripting operator, which inherently applies to a vector.
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� � � � Tom Gutman