Hi everyone,

These days I want to solve a system of nonlinear equations with matlab. In the equations, there are all four unkonwns, A(1),A(2),A(3)and A(4) to be solved but only three equations. therefore, the ‘levenberg-marquardt’ algorithm is applied to get the results. However, for physical meaning, an additional constraint is required, i.e. A(3)should be larger than zero. and with the ‘levenberg-marquardt’ algorithm, in the the obtained result, A(3) is negative.

Does anyone know how to add this constraint condition to fsolve ? Your help will be highly appreciated!Hi everyone,

These days I want to solve a system of nonlinear equations with matlab. In the equations, there are all four unkonwns, A(1),A(2),A(3)and A(4) to be solved but only three equations. therefore, the ‘levenberg-marquardt’ algorithm is applied to get the results. However, for physical meaning, an additional constraint is required, i.e. A(3)should be larger than zero. and with the ‘levenberg-marquardt’ algorithm, in the the obtained result, A(3) is negative.

Does anyone know how to add this constraint condition to fsolve ? Your help will be highly appreciated! Hi everyone,

These days I want to solve a system of nonlinear equations with matlab. In the equations, there are all four unkonwns, A(1),A(2),A(3)and A(4) to be solved but only three equations. therefore, the ‘levenberg-marquardt’ algorithm is applied to get the results. However, for physical meaning, an additional constraint is required, i.e. A(3)should be larger than zero. and with the ‘levenberg-marquardt’ algorithm, in the the obtained result, A(3) is negative.

Does anyone know how to add this constraint condition to fsolve ? Your help will be highly appreciated! fsolve MATLAB Answers — New Questions

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