- I1. A list of knowns.
- I2. A list of unknowns (together with an order which gives you priorities for eliminating them, see §).
- I3.
Collections
*C*and of equations in these knowns and unknowns.

The **output** of the NCProcess commands is a list of expressions
which are mathematically equivalent to
. When using
NCProcess1, this equivalent list
hopefully
has solved for some unknowns. The output
is
presented to the user as

- O1. Unknowns which have been solved for and equations which yield these unknowns.
- O2. Equations involving no unknowns.
- O3. Equations selected or created by the user. An example is given in the context of S1 and S2 below (§). There are also times during a strategy or prestrategy when one wants to introduce new variables and equations. This is illustrated in §.
- O4. Equations involving only one unknown.
- O5. Equations involving only 2 unknowns. etc.

We say that an equation which is in the output of
an NCProcess command is *digested* if it occurs in items
O1, O2 or O3 and is *undigested* otherwise.
Often, in practice, the digested polynomial equations are those
which are well understood.

We now turn to an example. In §, we compare the NCProcess commands to the Categorize operation which was described in §.

Wed Jul 3 10:27:42 PDT 1996