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the leading term of an object
LT(E):same type as E
where E has type IDEAL, MODULE, POLY, or VECTOR.
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If E is a polynomial this function returns the leading term of the
polynomial E with respect to the term-ordering of the polynomial ring
of E.
For the leading monomial, which includes the coefficient, use
LM
.
/**/ Use R ::= QQ[x,y,z]; -- the default term-ordering is DegRevLex
/**/ LT(y^2-x*z);
y^2
/**/ Use R ::= QQ[x,y,z], Lex;
/**/ LT(y^2-x*z);
x*z
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If E is a vector, LT(E) gives the leading term of E with respect to
the module term-ordering of the polynomial ring of E. For the leading
monomial, which includes the coefficient, use
LM
.
--***OBSOLETE MANUAL: WORK IN PROGRESS***
Use R ::= QQ[x,y];
V := Vector(0, x, y^2);
LT(V); -- the leading term of V w.r.t. the default term-ordering, ToPos
Vector(0, 0, y^2)
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Use R ::= QQ[x,y], PosTo;
V := Vector(0, x, y^2);
LT(V); -- the leading term of V w.r.t. PosTo
Vector(0, x, 0)
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If E is an ideal or module, LT(E) returns the ideal or module
generated by the leading terms of all elements of E, sometimes called
the
initial ideal or module.
/**/ Use R ::= QQ[x,y,z];
/**/ I := ideal(x-y, x-z^2);
/**/ LT(I);
ideal(x, z^2)
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