The call pivot(C, x, eqn) constructs a new set of equations in a form compatible with the forms used in simplex[setup], by solving the specified equation eqn for x, then substituting the result into C. This is equivalent to the standard simplex pivot on an array of coefficients.

To re-express the objective function f in terms of this new description, one can substitute the result of pivot into f.

If eqn is a list of equations, then  is used.  This is to facilitate easy user interaction with the function simplex[pivoteqn] used to choose an equation to use for the next pivot.

The command with(simplex,pivot) allows the use of the abbreviated form of this command.