Google Groups no longer supports new Usenet posts or subscriptions. Historical content remains viewable.
Dismiss

Working with Dyadics in mathematica

195 views
Skip to first unread message

Jason Sidabras

unread,
Feb 7, 2008, 10:32:48 PM2/7/08
to
Hello all,

I am currently doing a project where I am working on dyadic green's
functions for an electromagnetic problem.

My question comes in on how to handle the dyadic in mathematica with
the dot product of the source.

Currently I create the dyadic using my N(x,y,z) and M(x',y',z') as:
[...]
KroneckerProduct[Nemn[m, n, x, y, z, kg[m, n]],Memn[m, n, xp, yp, zp, -
kg[m, n]]]
[...]

This creates the correct dyadic for my problem. My issue comes in on
how to handle the source integral:

Integrate[
Gp[x,y, z, xp, 0, zp] .MoA[xp], {xp, a/2, a}, {zp, -d/2, d/2}] +
Integrate[
Gp[x, y, z, a, yp, zp].MoB[yp], {yp, 0, b}, {zp, -d/2, d/2}] +
Integrate[
Gp[x, y, z, xp, b, zp].MoC[xp], {xp, a, a/2}, {zp, -d/2, d/2}]

Am I missing something fundamental on how to handle the source
integral? Is Dot[] the correct function to use here?

Thank you in advance,

Jason

dh

unread,
Feb 9, 2008, 4:28:39 AM2/9/08
to

Hi Jason,

As far as I know, dyades are nothing else than special second rank

tensor in a special notation. Mathematica is geared towards tensor

notation. Therefore why not use tensor notation? Here is an example with

base vectors ei:

a= a1 e1 + a2 e2

b= b1 e1 + b2 e2

a b= a1 b1 e1 e1+ a1 b2 e1 e2 + a2 b1 e2 e1 + a2 ba e2 e2

the same in tensor notation:

a={a1,a2}

b={b1,b2}

a b would then correspond to a matrix:

Outer[Times,{a1,a2},{b1,b2}]={{a1 b1,a1 b2},{a2 b1,a2 b2}}

hope this helps, Daniel

0 new messages