Resolving the following system of equations:


On Wed, 10 Jun 2009, Julien Martin wrote:

< Hello,
< 
< I am trying to numerically resolve the following system of equations:
< 
< f9_8 = (f10,9 - c9 * f9_10 -b9 * f9_9)/a9
< f9_7 = (f10_8 - c8 * f9_9 - b8 * f9_8)/a8
< f9_6 = (f10_7 - c7 * f9_8 - b7 * f9_7)/a7
< ...
< f9_1 = (f10_2 - c2 * f9_3 - b2 * f9_2)/a2
< f9_0 = (f10_1 - c1 * f9_2 - b1 * f9_1)/a1
< 
< where the following are known:
< c1,c2,c3,...,c9
< b1,b2,b3,...,b9
< a1,a2,a3,...,a9
< f10_1,f10_2,f10_3,...,f10_9
< and also f9_10, f9_0
 
Look at the examples in the online help for linsolve:

? linsolve

You might also this about some labour-saving devices,
e.g.

eq[i] := f[9][i-1] = (f[10][i] - c[i]*f[9][i+1] etc. etc.

and then defining your equations by

eqns : makelist(eq[i],i,1,9);

Leo

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