How do I create a parametric expression?
- To: mathgroup at smc.vnet.net
- Subject: [mg68537] How do I create a parametric expression?
- From: axlq at spamcop.net (axlq)
- Date: Wed, 9 Aug 2006 04:19:05 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
I'm trying to figure out how to simplify a large expression so that it's
expressed in terms of a sub-expression that's factored into the larger
My expression looks like this:
-((1 + 2*n)*((a^4*k^2 + a^2*(-1 + k^2*(q - z)^2) + 2*(q - z)^2)
*Cos[k*Sqrt[a^2 + (q - z)^2]] - k*(a^2 - 2*(q - z)^2)
*Sqrt[a^2 + (q - z)^2]*Sin[k*Sqrt[a^2 + (q - z)^2]])
*Sin[((1 + 2*n)*Pi*z)/L])/(8*Pi*w*(a^2 + (q - z)^2)^(5/2))
Now, I *know* there are places in there were Sqrt[a^2+(q-z)^2] occurs,
either by itself or raised to various powers. If I want to define
...then how can I make Mathematica re-state my expression in terms
of R? The ReplaceRepated function doesn't seem to do the job.
I need to do this because I am translating the expressions into
Visual Basic code for an Excel application, and it would be nice to
find groupings of terms repeated throughout the expression that I
need to calculate only once.
Prev by Date:
Next by Date:
Re: Newbie question about column sums of arrays
Previous by thread:
RE: need mathematica's help for exploring a certain type of mapping
Next by thread:
Re: How do I create a parametric expression?