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  • To: mathgroup at smc.vnet.net
  • Subject: [mg94401] D
  • From: "Cetin Haftaoglu" <cetin.haftaoglu at bam.de>
  • Date: Fri, 12 Dec 2008 06:53:20 -0500 (EST)

Dear mathematica users,



I have a to  evaluate the Jacobian matrix from  a vector of function fi,
i=1,21 with the inner variables yi, i=1, 21 and epsj j=1,6.

So I have to evaluate D[f_i [yi,epsj] , y_j], i= 1, 21, j=1, 21. How can I
write this expression in a short form, without to say that the functions f_i
depent on the inner
variables yi. When I write D[f_i,yi] I receive 0 because mathematica thinks
that I want derive a Constant. When I say



D[f_i[y1,y2,y3,=85.,y21,eps1,=85eps6],y_j] ], i= 1, 21, j=1, 21



I get the right expression but a very great expression (output). How can I
reduce this output?



TIA,

Regards,



Cetin Haftaoglu

Arbeitsgruppe " Modellierung und Simulation in der Werkstoffmechanik"

BAM =96 Bundesanstalt f=FCr Materialforschung und -pr=FCfung
Fachgruppe V.2 =96Werkstoffmechanik



Unter den Eichen 87

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Email:  <mailto:cetin.haftaoglu at bam.de> cetin.haftaoglu at bam.de

Web:   www.bam.de


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