added test for automorphism on automorphism key

base2k/src/module.rs

@@ -74,15 +74,15 @@ impl<B: Backend> Module<B> {
     }
 
     // Returns gen^-1
-    pub fn galois_element_inv(&self, generator: i64) -> i64 {
-        if generator == 0 {
+    pub fn galois_element_inv(&self, gal_el: i64) -> i64 {
+        if gal_el == 0 {
             panic!("cannot invert 0")
         }
         ((mod_exp_u64(
-            generator.abs() as u64,
+            gal_el.abs() as u64,
             (self.cyclotomic_order() - 1) as usize,
         ) & (self.cyclotomic_order() - 1)) as i64)
-            * generator.signum()
+            * gal_el.signum()
     }
 }
 

base2k/src/vec_znx_ops.rs

@@ -574,6 +574,7 @@ impl<BACKEND: Backend> VecZnxOps for Module<BACKEND> {
         #[cfg(debug_assertions)]
         {
             assert_eq!(a.n(), self.n());
+            assert!(k & 1 != 0, "invalid galois element: must be odd but is {}", k);
         }
         unsafe {
             vec_znx::vec_znx_automorphism(