# entries(ToricDivisor) -- get the list of coefficients

## Synopsis

• Function: entries
• Usage:
entries D
• Inputs:
• D, ,
• Outputs:
• a list, of integers that are the coefficients of the corresponding irreducible torus-invariant divisors

## Description

This function returns the List whose $i$-th entry is the coefficient of $i$-th irreducible torus-invariant divisor. The indexing of the irreducible torus-invariant divisors is inherited from the indexing of the rays in the associated fan. This list can be viewed as an element of the group of torus-invariant Weil divisors.

Here are two simple examples.

 i1 : PP2 = toricProjectiveSpace 2; i2 : D1 = 2*PP2_0 - 7*PP2_1 + 3*PP2_2 o2 = 2*PP2 - 7*PP2 + 3*PP2 0 1 2 o2 : ToricDivisor on PP2 i3 : entries D1 o3 = {2, -7, 3} o3 : List i4 : assert( D1 == toricDivisor(entries D1, variety D1) ) i5 : assert all(entries toricDivisor PP2, i -> i === -1)
 i6 : D2 = toricDivisor convexHull (id_(ZZ^3) | - id_(ZZ^3)) o6 = D + D + D + D + D + D + D + D 0 1 2 3 4 5 6 7 o6 : 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}}) i7 : entries D2 o7 = {1, 1, 1, 1, 1, 1, 1, 1} o7 : List i8 : assert all(entries D2, i -> i === 1)