1. See which variables are present in an equation
2. Try to solve for each of those variables
3. You now have a set of solvable variables

For example:

x=external_func("str",y,z);

Will say y and z cannot be solved for (since the external C function is not known what it returns and you cannot invert it). While:

x=sin(y);

Can probably be inverted to y=arcsin(x) so both x and y are solvable.

Hi sjoelund.se,

Thank you! I understand the analytic concept of solvability.

I want more information about the numeric/automatic treatment.

I found this paper but I couldn't purchase it yet: "Dynamic tearing: efficiency enhancement of tearing methods by consideration of solvability criteria during runtime". Has anyone read this paper? Does it cover the topic?

Any other references?

Regards