MathGroup Archive 1999

[Date Index] [Thread Index] [Author Index]

Search the Archive

Symbolic Derivatives with respect to a vector

  • To: mathgroup at smc.vnet.net
  • Subject: [mg19929] Symbolic Derivatives with respect to a vector
  • From: Tim Lahey <tjlahey at mud.cgl.uwaterloo.ca>
  • Date: Tue, 21 Sep 1999 02:22:57 -0400
  • Organization: Computer Graphics Lab - University of Waterloo
  • Sender: owner-wri-mathgroup at wolfram.com

Hi,

I am wondering if Mathematica can handle symbolic derivatives with
respect to a vector. I am
performing a Method of Ritz approximation and I have to get the
Euler-Lagrange equations.

As an example, here is part of an equation I have to take the
derivatives of:

a'*Aij*a + a'*Aij*b + b'*Aij*a

where a and b are vectors, ' indicates a transpose, and Aij is a matrix.
In order to get
the Euler-Lagrange equations I have to take the derivatives with respect
to a and b. I
can do this by hand but is it possible to do this symbolically ?

Thanks,

Tim Lahey


----
Tim Lahey
M.A.Sc Student - Systems Design Engineering
University of Waterloo, Waterloo, Ontario, Canada
http://www.cgl.uwaterloo.ca/~tjlahey/



  • Prev by Date: Re: How to find solutions for conditioned equations?
  • Next by Date: Re: Coordinate Transformations
  • Previous by thread: Re: A (little?) problem in Number Theory
  • Next by thread: How can I get Divisors[n] from FactorInteger[n]?