Hello
I am trying to solve a set of non-linear equations in Mathematica 7.0
and every time it shows a error message :
"FindRoot::jsing: Encountered a singular Jacobian at the point
{B1,B2,B3,Ea1,Ea2,Ea3} =
{31.501,0.9004,38.5013,-1000.1,-1000.01,-2000.1}. Try perturbing the
initial point(s). >> ".
Sometimes it also shows this error message: "FindRoot::lstol: The line
search decreased the step size to within tolerance specified by
AccuracyGoal and PrecisionGoal but was unable to find a sufficient
decrease in the merit function. You may need more than
MachinePrecision digits of working precision to meet these tolerances.
>>" .
The equations that I am trying to solve are:
------------------------------------------------------------------------------------------------------------------------------------------------------------------
FindRoot[{Exp[B1 + Ea1*0.000374526] + Exp[B2 + Ea2*0.000374526] +
Exp[B3 + Ea3*0.000374526] == 0.0183,
Exp[B1 + Ea1*0.00037925] + Exp[B2 + Ea2*0.00037925] +
Exp[B3 + Ea3*0.00037925] == 0.00995,
Exp[B1 + Ea1*0.00038287] + Exp[B2 + Ea2*0.00038287] +
Exp[B3 + Ea3*0.00038287] == 0.0075,
Exp[2*B1 + 2*Ea1*0.000374526] + Exp[2*B2 + 2*Ea2*0.000374526] +
Exp[2*B3 + 2*Ea3*0.000374526] +
2*Exp[B1 + B2 + (Ea1 + Ea2)*0.000374526] +
2*Exp[B2 + B3 + (Ea3 + Ea2)*0.000374526] -
2*Exp[B1 + B3 + (Ea1 + Ea3)*0.000374526] == 0.01784*0.01784,
Exp[2*B1 + 2*Ea1*0.00037925] + Exp[2*B2 + 2*Ea2*0.00037925] +
Exp[2*B3 + 2*Ea3*0.00037925] +
2*Exp[B1 + B2 + (Ea1 + Ea2)*0.00037925] +
2*Exp[B2 + B3 + (Ea3 + Ea2)*0.00037925] -
2*Exp[B1 + B3 + (Ea1 + Ea3)*0.00037925] == 0.00983*0.00983,
Exp[2*B1 + 2*Ea1*0.00038287] + Exp[2*B2 + 2*Ea2*0.00038287] +
Exp[2*B3 + 2*Ea3*0.00038287] +
2*Exp[B1 + B2 + (Ea1 + Ea2)*0.00038287] +
2*Exp[B2 + B3 + (Ea3 + Ea2)*0.00038287] -
2*Exp[B1 + B3 + (Ea1 + Ea3)*0.00038287] == 0.00742*0.00742}, {B1,
40.001}, {B2, 110.9004}, {B3,
47.001309}, {Ea1, -1000.1}, {Ea2, -1000.01}, {Ea3, -2000.1},
MaxIterations -> Infinity, AccuracyGoal -> Infinity]
-------------------------------------------------------------------------------------------------------------------------------------------------------------
Can someone tell me if this can be solved in sympy and shouldn't the
Mathematica itself change the initial value and do a computation to
get the answer.
Thanks for any help in advance.
Nandan
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