how to solve equation using lambert w function

I= I_L - I_(o ) [e^((q(V+I*R_s )/a*k*T) )-1] - (V+I*R_s)/R_sh I want to solve this equation to know the value of R_s, a, R_sh using lambert w function. Except these three unknown all other parameters are known. Basically this equation is solar cell one diode model equation.

Answer 1

[Walter Roberson]

You cannot solve a single expression to get three variables. You could find the relationship between three variables but not the three individually.

[Manish Kumar]

Actually sir this is an implicit equation and i want to convert it in a explicit function in the form of I and V using lambert w function so please help how it can be convert in this form actually sir i am attaching you one paper so that you can tell me how they convert it explicit form so in that paper i want to know how they convert equation (1) in to equation (2)

[Walter Roberson]

Lambert W function is part of the Symbolic Toolbox lambertw()

If you are working entirely in the real domain then you could potentially use this File Exchange contribution

[Walter Roberson]

The paper already contains the explicit forms.

The paper is based upon solving several equations simultaneously. When you only have one equation in three variables then it is not possible to create a solution.

[Manish Kumar]

Yes , i know that it already given in paper but i know that how they convert equation (1) in to equation (2).. actually i want to know the steps to convert eqn (1) in to eqn (2)