diff --git a/src/@dseries/lag_.m b/src/@dseries/lag_.m
index 1cd1a05d44473dede7d3b7291fba279b42b31244..7c90ad43135485e10d7786fd277bedcbb61532c0 100644
--- a/src/@dseries/lag_.m
+++ b/src/@dseries/lag_.m
@@ -65,9 +65,13 @@ o.data = [NaN(p, vobs(o));  o.data(1:end-p,:)];
 
 for i=1:vobs(o)
     if isempty(o.ops)
-        o.ops(i) = {sprintf('lag(%s, %s)', o.name{i}, p)};
+        o.ops(i) = {sprintf('lag(%s, %s)', o.name{i}, int2str(p))};
     else
-        o.ops(i) = {sprintf('lag(%s, %s)', o.ops{i}, p)};
+        if isempty(o.ops{i})
+            o.ops(i) = {sprintf('lag(%s)', int2str(p))};
+        else
+            o.ops(i) = {sprintf('lag(%s, %s)', o.ops{i}, int2str(p))};
+        end
     end
 end
 
@@ -101,7 +105,7 @@ end
 %$
 %$ if t(1)
 %$     t(2) = dassert(ts.data,data,1e-15);
-%$     t(3) = isempty(ts.ops)
+%$     t(3) = isempty(ts.ops{1});
 %$ end
 %$
 %$ T = all(t);
diff --git a/src/@dseries/lead_.m b/src/@dseries/lead_.m
index 2c5aebe4b84cb69b24b9e0d733466cae2eec8228..a76269107fdcf7f93ac9658d6dc9ad5d99c3fb2e 100644
--- a/src/@dseries/lead_.m
+++ b/src/@dseries/lead_.m
@@ -64,10 +64,14 @@ end
 o.data = [  o.data(p+1:end,:); NaN(p, vobs(o));];
 
 for i=1:vobs(o)
-    if isempty(o.ops{i})
-        o.ops(i) = {sprintf('lead(%s, %s)', o.name{i}, p)};
+    if isempty(o.ops)
+        o.ops(i) = {sprintf('lead(%s, %s)', o.name{i}, int2str(p))};
     else
-        o.ops(i) = {sprintf('lead(%s, %s)', o.ops{i}, p)};
+        if isempty(o.ops{i})
+            o.ops(i) = {sprintf('lead(%s)', int2str(p))};
+        else
+            o.ops(i) = {sprintf('lead(%s, %s)', o.ops{i}, int2str(p))};
+        end
     end
 end
 
@@ -118,7 +122,7 @@ end
 %$
 %$ if t(1)
 %$     t(2) = dassert(ts.data,data,1e-15);
-%$     t(3) = isempty(ts.ops)
+%$     t(3) = isempty(ts.ops{1});
 %$ end
 %$
 %$ T = all(t);