diff --git a/src/cdomains/affineEquality/arrayImplementation/arrayMatrix.ml b/src/cdomains/affineEquality/arrayImplementation/arrayMatrix.ml
index dc24b7f641..9212cf501f 100644
--- a/src/cdomains/affineEquality/arrayImplementation/arrayMatrix.ml
+++ b/src/cdomains/affineEquality/arrayImplementation/arrayMatrix.ml
@@ -355,4 +355,7 @@ module ArrayMatrix: AbstractMatrix =
       map2i_with f m' v;
       m'
 
+    let swap_rows m j k =
+      failwith "TODO"
+
   end
\ No newline at end of file
diff --git a/src/cdomains/affineEquality/matrix.ml b/src/cdomains/affineEquality/matrix.ml
index 33a622d81a..3b45c12f91 100644
--- a/src/cdomains/affineEquality/matrix.ml
+++ b/src/cdomains/affineEquality/matrix.ml
@@ -71,4 +71,6 @@ sig
 
   val copy: t -> t
 
+  val swap_rows: t -> int -> int -> t
+
 end
\ No newline at end of file
diff --git a/src/cdomains/affineEquality/sparseImplementation/sparseMatrix.ml b/src/cdomains/affineEquality/sparseImplementation/listMatrix.ml
similarity index 100%
rename from src/cdomains/affineEquality/sparseImplementation/sparseMatrix.ml
rename to src/cdomains/affineEquality/sparseImplementation/listMatrix.ml