diff --git a/src/extract_matrix.h b/src/extract_matrix.h
index ffcde9234b5379a05821b5b74f506100de1bd90c..81332146545f908868f964a205b15f150c33359a 100644
--- a/src/extract_matrix.h
+++ b/src/extract_matrix.h
@@ -193,7 +193,7 @@ namespace extract_gmp_R
 
 	      // remove consecutive  duplicates
 	      it = std::unique(indJ.begin(),indJ.end());
-	      //indJ.erase(it,indJ.end());
+	      indJ.erase(it,indJ.end());
 
 	      if ( indJ.back() > 0){
 		clearVec<T>(copyAdress);
@@ -305,8 +305,8 @@ namespace extract_gmp_R
 	      // we should have indI like -1 -3 -7 -7 -12 ...
 
 	      // remove duplicates
-	      std::unique(indI.begin(),indI.end());
-	      //indI.erase(it,indI.end());
+	      it= std::unique(indI.begin(),indI.end());
+	      indI.erase(it,indI.end());
 
 	      if ( indI.back() > 0){
 		clearVec<T>(copyAdress);