Re: Derivative recurrence further

*To*: mathgroup at smc.vnet.net*Subject*: [mg72713] Re: Derivative recurrence further*From*: "dimitris" <dimmechan at yahoo.com>*Date*: Tue, 16 Jan 2007 03:07:34 -0500 (EST)*References*: <eofikq$gc1$1@smc.vnet.net>

Supposing you work within the elasticity theory one good place for Mathematica notebooks is the folowing link http://www-personal.umich.edu/~jbarber/elasticity/book.html It contains Mathematica notebooks (as well relevant material for anothe CAS) for the material inside Barber's Book Elasticity (Second Edition). Also of great interest are the following links: http://documents.wolfram.com/applications/structural/ http://zen.uta.edu/research/cas.html Hope that I help you a little! Dimitris KFUPM wrote: > Dear All > > I have the following > > u1(x,x,z,t) = z f1(x,y,t) > u2(x,y,z,t) = z f2(x,y,t) > u3(x,y,z,t) = z f3(x,y,t) > > which is basically the displacement fied. I want to compute the strain > which is given in indecial notation as: > > Eij = 1/2( dui/dxj + duj/dxj ) where i, j, k go from 1 to 3,,, x1=x, x2 > =y, x3=z, > > I want mathematica to calculate the strain Eij autmoatically, > > for example > > when i = 1 and j= 2 > > E12 =1/2 (du1/dx2+du2/dx1 ) but x1 =x and x2 =y > > therefore > > E12 =1/2 (du1/dy + du2/dx) = 1/2 ( z df1/dx + z df2/dy),,, where f1, > f2 and f3 are arbitrary functions. > > Eij should generate 3 by 3 matrix containing the strain components. > Frankly, i don't know how to do it using mathematica and i would > appreciate any help in this regard. > > > Thanks in anticipation