From f70fe230e34bb8b3335b27aa2aac2791b26ae51d Mon Sep 17 00:00:00 2001
From: Eran Assaf <assaferan@gmail.com>
Date: Tue, 21 Jan 2025 16:32:32 -0500
Subject: [PATCH 1/2] fixing issue 29

---
 ModFrmGL2/ModSymA             |  2 +-
 ModFrmGL2/Tests/AtkinLehner.m |  6 +++---
 ModFrmGL2/Tests/Issue29.m     | 15 +++++++++++++++
 ModFrmGL2/Tests/Shimura.m     | 13 ++++++++++---
 4 files changed, 29 insertions(+), 7 deletions(-)
 create mode 100644 ModFrmGL2/Tests/Issue29.m

diff --git a/ModFrmGL2/ModSymA b/ModFrmGL2/ModSymA
index 790be2b8..eaded473 160000
--- a/ModFrmGL2/ModSymA
+++ b/ModFrmGL2/ModSymA
@@ -1 +1 @@
-Subproject commit 790be2b843ecb40f15073c2a4a979cabbb69fb87
+Subproject commit eaded473b5a71e3bd79c97ed13fe3c90f8373d5f
diff --git a/ModFrmGL2/Tests/AtkinLehner.m b/ModFrmGL2/Tests/AtkinLehner.m
index 8870b23b..d86460d0 100644
--- a/ModFrmGL2/Tests/AtkinLehner.m
+++ b/ModFrmGL2/Tests/AtkinLehner.m
@@ -14,8 +14,8 @@ procedure Test_AtkinLehner(numchecks : maxN := 15, maxk := 6)
    end for;
 end procedure;
 
-procedure Test_IssueKoutsianas()
-  printf "Testing issue in mail from Koutsianas... ";
+procedure Test_Issue30()
+  printf "Testing issue #30";
   gens := [[1,3,12,3],[1,1,12,7],[1,3,0,3],[1,0,2,3]];
   N := 16;
   H_N := sub<GL(2,Integers(N)) | gens>;
@@ -27,4 +27,4 @@ procedure Test_IssueKoutsianas()
 
 Test_AtkinLehner(5);
 
-Test_IssueKoutsianas();
+Test_Issue30();
diff --git a/ModFrmGL2/Tests/Issue29.m b/ModFrmGL2/Tests/Issue29.m
new file mode 100644
index 00000000..ff8c1307
--- /dev/null
+++ b/ModFrmGL2/Tests/Issue29.m
@@ -0,0 +1,15 @@
+procedure Test_Issue29()
+  printf "Testing issue #29";
+  P<x,y,z,u,v,w> := ProjectiveSpace(Rationals(),5);
+  gens := [[4,0,0,3], [0,1,1,0], [2,0,0,2]];
+  N := 11;
+  H_N := sub<GL(2, Integers(N)) | gens>;
+  H := PSL2Subgroup(H_N);
+  M := ModularSymbols(H, 2, Rationals(), 0);
+  S := CuspidalSubspace(M);
+  XD10nred<[x]>, basisD10 := ModularCurve(H);
+  assert IsCurve(XD10nred);
+  assert not IsHyperelliptic(XD10nred);
+end procedure;
+
+Test_Issue29();
diff --git a/ModFrmGL2/Tests/Shimura.m b/ModFrmGL2/Tests/Shimura.m
index 64c5f357..b35564bd 100644
--- a/ModFrmGL2/Tests/Shimura.m
+++ b/ModFrmGL2/Tests/Shimura.m
@@ -8,11 +8,18 @@ function Test_Shimura(N)
 //    mat_gens := [[-1,0,0,-1],[1,t,0,1]] cat [[a,0,0,1] : a in h_gens]
 //		cat [[1,0,0,d] : d in all_gens];
 //    gamma := PSL2Subgroup(sub<GL(2, Integers(N)) | mat_gens>);
-    gamma := GammaShimura(N, U, phi, H`subgroup, t);
+    gamma := GammaShimura(U, phi, H`subgroup, t);
 //   M := ModularSymbols(gamma, 2, Rationals(), 0);
     M := ModularSymbols(gamma);
     S := CuspidalSubspace(M);
-    D := NewformDecomposition(S);
-    // D := Decomposition(S, HeckeBound(S));
+    // D := NewformDecomposition(S);
+    D := Decomposition(S, HeckeBound(S));
     return D, S;
 end function;
+
+num_times := 5;
+max_N := 10;
+for i in [1..num_times] do
+    N := Random(max_N);
+    D, S := Test_Shimura(N);
+end for;

From 5ae2f5f929566cb0f351babcc1dd0d3f5265e8ef Mon Sep 17 00:00:00 2001
From: Eran Assaf <assaferan@gmail.com>
Date: Tue, 21 Jan 2025 16:38:49 -0500
Subject: [PATCH 2/2] not allowing for N = 1 which causes issues

---
 ModFrmGL2/Tests/Shimura.m | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ModFrmGL2/Tests/Shimura.m b/ModFrmGL2/Tests/Shimura.m
index b35564bd..fc0ad18a 100644
--- a/ModFrmGL2/Tests/Shimura.m
+++ b/ModFrmGL2/Tests/Shimura.m
@@ -20,6 +20,6 @@ function Test_Shimura(N)
 num_times := 5;
 max_N := 10;
 for i in [1..num_times] do
-    N := Random(max_N);
+    N := Random(2, max_N);
     D, S := Test_Shimura(N);
 end for;