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2 problems!

  • To: mathgroup at smc.vnet.net
  • Subject: [mg120311] 2 problems!
  • From: Mary R <mathematica023 at gmail.com>
  • Date: Mon, 18 Jul 2011 06:14:28 -0400 (EDT)

Hi to everyone!
I've got two problems that for me is quite difficult...
1. I want to calculate in the same cicle Do this coefficient a,b,V and
evaluate the difference beetween this calculate coefficient and the real
parameter areal,breal,Vreal and evaluate a coefficient Omega.
I was able to calculate only the coefficient a,b,V;
e.g.
value u , w {2,2}:
{{{a->-2.57258*10^7,b->-1108.81,V->679.954},{a->1.59736*10^6,b->-210.798,V->380.617},{a->1.3548*10^7,b->53.9538,V->292.367}},
*3.03895*10^-8 a*,-*3.34268*10^12+a,128465. +b,-200+V*}
can you hel me?
2. The second problem is to change the result from InputForm in a table to
export in Excel;
 that is trasform my result
(e.g.)
value u , w {2,2}:
{{{a->-2.57258*10^7,b->-1108.81,V->679.954},{a->1.59736*10^6,b->-210.798,V->380.617},{a->1.3548*10^7,b->53.9538,V->292.367}},3.03895*10^-8
a,-3.34268*10^12+a,128465. +b,-200+V}
in a table!
---------------------listing-----------------------
pression = (R Subscript[T, c])/(V - b) - a/(
    b^2 w + b u V + V^2) /. {Subscript[T, c] -> 425.1,  R -> 83.14};
der1 = D[pression, V] == 0;
der2 = D[pression, {V, 2}] == 0;
p = 37.96 - pression == 0;
Vreal = 200;
areal = 3.3426778202443823`*^12;
breal = -128465.27253980785`;
\[CapitalPsi] = \!\(TraditionalForm\`
\*FractionBox[\(a\ P\), \(
\*SuperscriptBox[\(R\), \(2\)]\
\*SuperscriptBox[\(T\), \(2\)]\)]\  /. {T -> 425.1, \ \ R -> 83.14,
      P -> 37.96}\);
Do[sol = Solve[Rationalize[der1 && der2 && p, 0], {a, b, V},
    Reals] // N; \[CapitalPsi] -> a; A = a - areal; B = b - breal;
 volume = V - Vreal;
 Print[ "value u , w, Omega,difference ", {u, w},
  ": ", {sol, \[CapitalPsi], A, B, volume}], {u,-100, 100,0.1}, {u,-100,
100,0.1}]
{a, b, V} /. sol

Thanks a lot in advance for your help.
MR



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