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Arbitrary equations systems

Here we define a list of equations separated by a newline character. Each equation defines a recursive expression that this variable has to fulfill eg. x = cos(y) + x defines an equation for the variable $ x$ and its dependence on the variables $ y$ and $ x$. A formal grammar in short could look like this:

      $\displaystyle \langle{Equation}\rangle \textrm{ ::= } \langle{Variable}\rangle \textrm{\textbf{=}} \langle{Expression}\rangle$

I am not going to go in details how expressions in our grammar looks like, see for more details what expressions are allowed. List of supported functions is available here: On top of that we added functions $ \max$ and $ \min$ with arbitrary number of arguments. Obviously if such function occurs in our equation system, Newton method won't work as it won't be able to differentiate them.

Dominik Wojtczak 2006-10-31