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LT --
the leading term of an object
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LT(I: RINGELEM): RINGELEM
LT(I: IDEAL): IDEAL
LT(I: MODULEELEM): MODULEELEM
LT(I: MODULE): MODULE |
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 MODULEELEM,
LT(E)
gives the leading term
of
E
with respect to the module term-ordering of
E
.
For the leading monomial, which includes the coefficient, use
LM
.
/**/ use R ::= QQ[x,y];
/**/ R3 := NewFreeModule(R,3);
/**/ LT(ModuleElem(R3, [0, x, y^2]));
[0, 0, y^2]
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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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