adds function for dim computation

Author: RafaelDavidMohr

src/algorithms/other-algorithms.jl

@@ -1,3 +1,31 @@
 function dimension(I::Ideal{T}) where T <: MPolyRingElem
 
+    gb = isempty(values(I.gb)) ? groebner_basis(I) : first(values(I.gb))
+    R = parent(first(gb))
+    res = [trues(ngens(R))]
+
+    lms = (Nemo.leading_monomial).(gb)
+    for lm in lms
+        to_del = Int[]
+        new_miss = BitVector[]
+        for (i, mis) in enumerate(res)
+            nz_exps_inds = findall(e -> !iszero(e),
+                                   first(Nemo.exponent_vectors(lm)))
+            ind_var_inds = findall(mis)
+            if issubset(nz_exps_inds, ind_var_inds)
+                for j in nz_exps_inds
+                    new_mis = copy(mis)
+                    new_mis[j] = false
+                    push!(new_miss, new_mis)
+                end
+                push!(to_del, i)
+            end
+        end
+        deleteat!(res, to_del)
+        append!(res, new_miss)
+        unique!(res)
+    end
+
+    max_length = maximum(mis -> length(findall(mis)), res)
+    return max_length
 end