Useless equality constraints

A user-supplied equality constraint could be implicitly contained in the stoichiometric constraints or in other equality constraints. In a mathematical sense, this means that the constraint is linearly dependent on a set of other constraints. The easiest way to find these redundant constraints would be calculating the rank of the constraint system. If the matrix is rank deficient, there are linearly dependent constraints. If the system is also not solvable, there are conflicting constraints. With a little effort, a linear dependent set of constraints could be found.

The user then needs a warning stating the linear dependent set of constraints, because most likely he has made mistakes in his metabolic model.