Assign symbolic results to a function

[hgog]

When I try to inverse transform expressions of type:

1/((s+A)(s+B)(s+C)(s+D)(s+E))

I get the following message:

"The symbolic result returned is too large to display, but it can be used in subsequent calculations if assigned to a function or variable"

In practice, how do I do this?

 

[GregLocock]

f(s,A,B,C,D,E):=1/((s+A)*(s+B)*(s+C)*(s+D)*(s+E))
f(1,1,1,1,1,1)=0.03
at a rough guess, that is you can get a numeric solution but not a symbolic one

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[PNachtwey]

convert to partial fractions and then do the transform on each partial fraction.


Peter Nachtwey
Delta Computer Systems

http://www.deltamotion.com

 

[philipoakley]

You can simply assign =) the result.

That is you get:

Eqn1:=Solve_my_expression -> Long_results

where the 'Solve_my_expression ->' is the bit you already have. It will still give the same message, but Eqn1 will be the undisplayable formula.

You can even use

My_function(t):=Eqn1-> (long result)

Where 't' is a variable name used in the (hidden) long result to create the new function.

Thus you will see that the live symbolic work is done first and then it is as if the result stands in it place for a regular mathcad (numeric) expression definition.

Also look up the 'undefine' where you sat a:=a etc so that the symbolic calculation doesn't backtrack all the way to your defined numbers, but stops at the variable names you chose You can even do the 'undefine' on intermediate variables if you want to keep them in the symbolic solution rather than the base variables.

Philip