Isolating shifting morphs

Author: Sparks29032

src/diffpy/pdfmorph/morphs/morphshift.py

@@ -47,9 +47,13 @@ class MorphShift(Morph):
 
     def morph(self, x_morph, y_morph, x_target, y_target):
         """Apply the shifts."""
-        if self.hshift is None:
+        try:
+            self.hshift
+        except AttributeError:
             self.hshift = 0
-        if self.vshift is None:
+        try:
+            self.vshift
+        except AttributeError:
             self.vshift = 0
 
         Morph.morph(self, x_morph, y_morph, x_target, y_target)

src/diffpy/pdfmorph/pdfmorphapp.py

@@ -369,19 +369,11 @@ def single_morph(parser, opts, pargs, stdout_flag=True):
         chain.append(morphs.MorphShift())
         config["hshift"] = hshift_in
         refpars.append("hshift")
-        if opts.vshift is None:
-            vshift_in = 0
-            config["vshift"] = vshift_in
-            refpars.append("vshift")
     if opts.vshift is not None:
         vshift_in = opts.vshift
         chain.append(morphs.MorphShift())
         config["vshift"] = vshift_in
         refpars.append("vshift")
-        if opts.hshift is None:
-            hshift_in = 0
-            config["hshift"] = hshift_in
-            refpars.append("hshift")
     # Smear
     if opts.smear is not None:
         smear_in = opts.smear