diff --git a/src/fundamental_period.rs b/src/fundamental_period.rs
index 6bb3508..788cafb 100644
--- a/src/fundamental_period.rs
+++ b/src/fundamental_period.rs
@@ -61,8 +61,7 @@ fn compute_c_0neg<T>(
         + Assign<&'a T>
         + AddAssign<&'a T>
         + SubAssign<&'a T>
-        + MulAssign<&'a T>
-        + std::fmt::Display,
+        + MulAssign<&'a T>,
 {
     let mut a: Vec<_> = (0..q.ncols()).map(|_| template_var.clone()).collect();
     let mut tmp_num0 = template_var.clone();
@@ -367,8 +366,7 @@ where
         + SubAssign<&'a T>
         + Send
         + Sync
-        + RecipMut
-        + std::fmt::Display,
+        + RecipMut,
 {
     let curves = &sg.elements;
     let h11 = q.ncols();
diff --git a/src/instanton.rs b/src/instanton.rs
index 4e93812..c610768 100644
--- a/src/instanton.rs
+++ b/src/instanton.rs
@@ -137,7 +137,7 @@ fn compute_inst_thread<T>(
     poly_props: &PolynomialProperties<T>,
     np: &mut NumberPool<T>,
     intnum_dict: &HashMap<(usize, usize, usize), i32>,
-    cy_dim: u32,
+    is_threefold: bool,
 ) where
     for<'a> T: Clone
         + AddAssign<&'a T>
@@ -171,7 +171,7 @@ fn compute_inst_thread<T>(
                 intnum_ind[0] = t;
                 intnum_ind[1] = a;
                 intnum_ind[2] = b;
-                if cy_dim == 3 {
+                if is_threefold {
                     intnum_ind.sort_unstable();
                 }
                 let Some(x) = intnum_dict.get(&(intnum_ind[0], intnum_ind[1], intnum_ind[2]))
@@ -250,7 +250,7 @@ pub fn compute_instanton_data<T>(
     intnum_idxpairs: &HashSet<(usize, usize)>,
     n_indices: usize,
     intnum_dict: &HashMap<(usize, usize, usize), i32>,
-    cy_dim: u32,
+    is_threefold: bool,
 ) -> Result<InstantonData<T>, PolynomialError>
 where
     for<'a> T: Clone
@@ -342,7 +342,15 @@ where
             let tx = tx.clone();
             let tasks = Arc::clone(&tasks_inst_iter);
             s.spawn(|| {
-                compute_inst_thread(tasks, tx, &f_poly, poly_props, np, intnum_dict, cy_dim);
+                compute_inst_thread(
+                    tasks,
+                    tx,
+                    &f_poly,
+                    poly_props,
+                    np,
+                    intnum_dict,
+                    is_threefold,
+                );
             });
         }
         drop(tx);
@@ -418,7 +426,7 @@ mod tests {
         let (intnum_dict, intnum_idxpairs) = result.unwrap();
 
         let inst_data =
-            compute_instanton_data(fp, &poly_props, &intnum_idxpairs, 2, &intnum_dict, 3);
+            compute_instanton_data(fp, &poly_props, &intnum_idxpairs, 2, &intnum_dict, true);
         assert!(inst_data.is_ok());
         let inst_data = inst_data.unwrap();
 
diff --git a/src/series_inversion.rs b/src/series_inversion.rs
index 7d699bc..e825764 100644
--- a/src/series_inversion.rs
+++ b/src/series_inversion.rs
@@ -81,7 +81,7 @@ where
     for (i, diff) in closest_curve_diff.iter().enumerate() {
         let tmp_poly = match diff.cmp(&0) {
             Ordering::Greater => expalpha[i].0.pow(*diff, poly_props, np).unwrap(),
-            Ordering::Less => expalpha[i].0.pow(-*diff, poly_props, np).unwrap(),
+            Ordering::Less => expalpha[i].1.pow(-*diff, poly_props, np).unwrap(),
             _ => {
                 continue;
             }
@@ -215,6 +215,7 @@ where
         + MulAssign<u32>
         + PartialEq<i32>
         + PartialOrd<T>
+        + PartialOrd<f32>
         + SubAssign<&'a T>
         + Send
         + Sync
@@ -246,18 +247,24 @@ where
 
     let InstantonData { mut inst, expalpha } = inst_data;
 
-    let all_degs: HashSet<_> = poly_props.semigroup.degrees.iter().cloned().collect();
+    let all_degs: HashSet<_> = poly_props
+        .semigroup
+        .degrees
+        .iter()
+        .cloned()
+        .filter(|c| *c != 0)
+        .collect();
     let mut distinct_degs: Vec<_> = all_degs.into_iter().collect();
     distinct_degs.sort_unstable();
 
     for d in distinct_degs.iter() {
         let mut vec_deg = Vec::new();
         let mut qn_to_compute = Vec::new();
-        let mut gv_qn_to_compute = Vec::new();
+        let mut gv_qn_to_compute = HashMap::new();
         let mut h22gv_qn_to_compute = HashMap::new();
         // First find the points of interest
         for (i, dd) in poly_props.semigroup.degrees.iter().enumerate() {
-            match d.cmp(dd) {
+            match dd.cmp(d) {
                 Ordering::Equal => {
                     vec_deg.push(i);
                 }
@@ -288,17 +295,17 @@ where
                     tmp_gv_rounded.round_mut();
                     tmp_gv -= &tmp_gv_rounded;
                     tmp_gv.abs_mut();
-                    if tmp_gv > poly_props.zero_cutoff {
+                    if tmp_gv > 1e-3 {
                         return Err(SeriesInversionError::NonIntegerGVError);
                     }
                     tmp_gv.assign(&tmp_gv_rounded);
                     tmp_gv.abs_mut();
-                    if tmp_gv <= poly_props.zero_cutoff {
+                    if tmp_gv < 0.5 {
                         continue;
                     }
                     final_gv.insert((j as u32, 0), tmp_gv_rounded.clone());
                     qn_to_compute.push(j);
-                    gv_qn_to_compute.push(tmp_gv_rounded.clone());
+                    gv_qn_to_compute.insert(j, tmp_gv_rounded.clone());
                 } else {
                     tmp_gv_rounded.assign(&tmp_gv);
                     tmp_gv_rounded.abs_mut();
@@ -307,7 +314,7 @@ where
                     }
                     final_gv.insert((j as u32, 0), tmp_gv.clone());
                     qn_to_compute.push(j);
-                    gv_qn_to_compute.push(tmp_gv.clone());
+                    gv_qn_to_compute.insert(j, tmp_gv.clone());
                 }
             }
         } else {
@@ -321,12 +328,12 @@ where
                         tmp_gv_rounded.round_mut();
                         tmp_gv -= &tmp_gv_rounded;
                         tmp_gv.abs_mut();
-                        if tmp_gv > poly_props.zero_cutoff {
+                        if tmp_gv > 1e-3 {
                             return Err(SeriesInversionError::NonIntegerGVError);
                         }
                         tmp_gv.assign(&tmp_gv_rounded);
                         tmp_gv.abs_mut();
-                        if tmp_gv <= poly_props.zero_cutoff {
+                        if tmp_gv < 0.5 {
                             continue;
                         }
                         final_gv.insert((j as u32, k as u32), tmp_gv_rounded.clone());
@@ -385,7 +392,7 @@ where
                             continue;
                         }
                         let mut tmp_poly = li2qn.clone(&mut main_pool);
-                        tmp_gv.assign(&gv_qn_to_compute[j as usize]);
+                        tmp_gv.assign(&gv_qn_to_compute[&(j as usize)]);
                         tmp_gv *= poly_props.semigroup.elements[(k, j as usize)];
                         tmp_poly.mul_scalar_assign(&tmp_gv);
                         inst_k.sub_assign(&tmp_poly, &mut main_pool);