next | previous | forward | backward | up | top | index | toc | Macaulay2 web site
NormalToricVarieties :: expression(ToricDivisor)

expression(ToricDivisor) -- get the expression used to format for printing

Synopsis

Description

This method is the primary function called upon by << (missing documentation) to format for printing. It assumes that D is well-defined.

When the underlying normal toric variety has not been assigned a global variable, the i-th irreducible torus-invariant Weil divisor is displayed as Di. However, if the underlying normal toric variety has been assigned a global variable X, the i-th irreducible torus-invariant Weil divisor is displayed as Xi. In either case, an arbitrary torus-invariant Weil divisor is displayed as an integral linear combination of these expressions.

i1 : toricDivisor({2,-7,3}, toricProjectiveSpace 2)

o1 = 2*D  - 7*D  + 3*D
        0      1      2

o1 : ToricDivisor on normalToricVariety((({{-1, -1}, {1, 0}, {0, 1}}(,({{0, 1}, {0, 2}, {1, 2}} )))))
i2 : toricDivisor convexHull (id_(ZZ^3) | - id_(ZZ^3))

o2 = D  + D  + D  + D  + D  + D  + D  + D
      0    1    2    3    4    5    6    7

o2 : ToricDivisor on normalToricVariety((({{1, 1, 1}, {-1, 1, 1}, {1, -1, 1}, {-1, -1, 1}, {1, 1, -1}, {-1, 1, -1}, {1, -1, -1}, {-1, -1, -1}}(,({{0, 1, 2, 3}, {0, 1, 4, 5}, {0, 2, 4, 6}, {1, 3, 5, 7}, {2, 3, 6, 7}, {4, 5, 6, 7}} )))))
i3 : PP2 = toricProjectiveSpace 2;
i4 : D1 = toricDivisor({2,-7,3}, PP2)

o4 = 2*PP2  - 7*PP2  + 3*PP2
          0        1        2

o4 : ToricDivisor on normalToricVariety((({{-1, -1}, {1, 0}, {0, 1}}(,({{0, 1}, {0, 2}, {1, 2}} )))))
i5 : D2 = 2 * PP2_0 - 7 * PP2_1 + 3 * PP2_2

o5 = 2*PP2  - 7*PP2  + 3*PP2
          0        1        2

o5 : ToricDivisor on normalToricVariety((({{-1, -1}, {1, 0}, {0, 1}}(,({{0, 1}, {0, 2}, {1, 2}} )))))
i6 : assert(D1 == D1)

See also