- Usage:
`leadTerm(n,f)`

- Function: leadTerm
- Inputs:
`n`, an integer`f`, a ring element, in a polynomial ring

- Outputs:
- a ring element, the lead term of
`f`using the first`n`parts of the monomial order

- a ring element, the lead term of

Returns the sum of the terms of `f` which are greatest using the first `n` parts of the monomial order in the ring of `f`.

In the following example, the lead terms using the first part refers to all the monomials that have the lead monomial in the indeterminates `a` and `b`. This has a effect similar to selecting leadTerm in the ring `QQ[c,d][a,b]`.

i1 : R = QQ[a..d, MonomialOrder => ProductOrder{2,2}]; |

i2 : leadTerm(1, (c+d)*a^3 - c^100*a - 1) 3 3 o2 = a c + a d o2 : R |

- selectInSubring -- select columns in a subring