The function pdimStats computes the mean and standard deviation of the projective dimension of elements in the list:
i1 : R=ZZ/101[a,b,c]; |
i2 : ideals = {monomialIdeal(a^3,b,c^2), monomialIdeal(a^3,b,a*c)} 3 2 3 o2 = {monomialIdeal (a , b, c ), monomialIdeal (a , b, a*c)} o2 : List |
i3 : pdimStats(ideals) o3 = (3, 0) o3 : Sequence |
The function can also output the projective dimension tally as follows:
i4 : R=ZZ/101[a,b,c]; |
i5 : ideals = {monomialIdeal(a,c),monomialIdeal(b),monomialIdeal(a^2*b,b^2)} 2 2 o5 = {monomialIdeal (a, c), monomialIdeal b, monomialIdeal (a b, b )} o5 : List |
i6 : pdimStats(ideals, ShowTally=>true) o6 = (1.66667, .471405, Tally{1 => 1}) 2 => 2 o6 : Sequence |
The following examples use the existing functions randomMonomialIdeals to automatically generate a list of ideals, rather than creating the list manually:
i7 : ideals = randomMonomialIdeals(4,3,1.0,3) o7 = {monomialIdeal (x , x , x , x ), monomialIdeal (x , x , x , x ), 1 2 3 4 1 2 3 4 ------------------------------------------------------------------------ monomialIdeal (x , x , x , x )} 1 2 3 4 o7 : List |
i8 : pdimStats(ideals) o8 = (4, 0) o8 : Sequence |
i9 : ideals = randomMonomialIdeals(4,6,0.01,10) 2 3 2 3 o9 = {monomialIdeal(x x x ), monomialIdeal (x x x , x x x ), monomialIdeal 2 3 4 1 2 4 1 3 4 ------------------------------------------------------------------------ 5 3 2 2 2 (), monomialIdeal (x x , x x , x x ), monomialIdeal(x x ), 2 3 2 3 1 4 2 3 ------------------------------------------------------------------------ 2 2 5 4 2 2 monomialIdeal(x x ), monomialIdeal (x x , x x x , x x x x ), 1 4 1 3 2 3 4 1 2 3 4 ------------------------------------------------------------------------ 2 3 2 2 2 monomialIdeal(x x ), monomialIdeal (x x x , x x x , x ), 2 3 1 3 4 1 3 4 4 ------------------------------------------------------------------------ 3 monomialIdeal(x x x )} 2 3 4 o9 : List |
i10 : pdimStats(ideals) o10 = (1.6, 1.0198) o10 : Sequence |
The object pdimStats is a method function with options.