Singular Manual: irrRealizationDim

| #### D.13.5.2 irrRealizationDim Procedure from library `realizationMatroids.lib` (see realizationMatroids_lib). Usage: irrRealizationDim(I,C); where I is a homogeneous linear ideal defining the projective plane Y = V(I) and C is a list of intvectors such that each intvector represents a one-dimensional cone in the tropical fan curve whose irreducible relative realizability should be checked. This representation is done in the following way: a one-dimensional cone K is represented by a vector w whose equivalence class [w] in R^n/<1> can be written as [w] = m*[v] where [v] is the primitive generator of K and m is the weight of K. Returns: the dimension of the irreducible relative realization space of C with respect to Y, and -1 if the irreducible realization space is empty. Example:
    LIB "realizationMatroids.lib";
    ring r = 0,(x(1..4)),dp;
    ideal I = x(1)+x(2)+x(3)+x(4);
    list C = list(intvec(2,2,0,0),intvec(0,0,2,2));
    //C represents the tropical fan curve which consists of the cones
    //cone([(1,1,0,0)]) and cone([(1,1,0,0)]), both with weight 2
    realizationDim(I,C);
    ==> 0
    irrRealizationDim(I,C);
    ==> -1

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