diff --git a/matlab/AddCPWPort.m b/matlab/AddCPWPort.m
index ba4fc4a..d5e9b5f 100644
--- a/matlab/AddCPWPort.m
+++ b/matlab/AddCPWPort.m
@@ -84,12 +84,12 @@ for n=1:2:numel(varargin)
         end
     elseif (strcmp(varargin{n},'Feed_R')==1);
         feed_R = varargin{n+1};
-        if (numel(feed_shift)>1)
+        if (numel(feed_R)>1)
             error 'Feed_R must be a scalar value'
         end
     elseif (strcmp(varargin{n},'MeasPlaneShift')==1);
         measplanepos = varargin{n+1};
-        if (numel(feed_shift)>1)
+        if (numel(measplanepos)>1)
             error 'MeasPlaneShift must be a scalar value'
         end
     elseif (strcmp(varargin{n},'ExcitePort')==1);
diff --git a/matlab/AddCoaxialPort.m b/matlab/AddCoaxialPort.m
index 45c0d2b..9c94723 100644
--- a/matlab/AddCoaxialPort.m
+++ b/matlab/AddCoaxialPort.m
@@ -66,12 +66,12 @@ for n=1:2:numel(varargin)
         end
     elseif (strcmp(varargin{n},'Feed_R')==1);
         feed_R = varargin{n+1};
-        if (numel(feed_shift)>1)
+        if (numel(feed_R)>1)
             error 'Feed_R must be a scalar value'
         end
     elseif (strcmp(varargin{n},'MeasPlaneShift')==1);
         measplanepos = varargin{n+1};
-        if (numel(feed_shift)>1)
+        if (numel(measplanepos)>1)
             error 'MeasPlaneShift must be a scalar value'
         end
     elseif (strcmp(varargin{n},'ExciteAmp')==1);
diff --git a/matlab/AddMSLPort.m b/matlab/AddMSLPort.m
index 462db14..bd4c6ab 100644
--- a/matlab/AddMSLPort.m
+++ b/matlab/AddMSLPort.m
@@ -85,12 +85,12 @@ for n=1:2:numel(varargin)
         end
     elseif (strcmp(varargin{n},'Feed_R')==1);
         feed_R = varargin{n+1};
-        if (numel(feed_shift)>1)
+        if (numel(feed_R)>1)
             error 'Feed_R must be a scalar value'
         end
     elseif (strcmp(varargin{n},'MeasPlaneShift')==1);
         measplanepos = varargin{n+1};
-        if (numel(feed_shift)>1)
+        if (numel(measplanepos)>1)
             error 'MeasPlaneShift must be a scalar value'
         end
     elseif (strcmp(varargin{n},'ExcitePort')==1);
diff --git a/matlab/AddStripLinePort.m b/matlab/AddStripLinePort.m
index 70dd065..af73e54 100644
--- a/matlab/AddStripLinePort.m
+++ b/matlab/AddStripLinePort.m
@@ -84,12 +84,12 @@ for n=1:2:numel(varargin)
         end
     elseif (strcmp(varargin{n},'Feed_R')==1);
         feed_R = varargin{n+1};
-        if (numel(feed_shift)>1)
+        if (numel(feed_R)>1)
             error 'Feed_R must be a scalar value'
         end
     elseif (strcmp(varargin{n},'MeasPlaneShift')==1);
         measplanepos = varargin{n+1};
-        if (numel(feed_shift)>1)
+        if (numel(measplanepos)>1)
             error 'MeasPlaneShift must be a scalar value'
         end
     elseif (strcmp(varargin{n},'ExcitePort')==1);