diff --git a/pyEPR/ansys.py b/pyEPR/ansys.py
index 8a84c99..29530f8 100644
--- a/pyEPR/ansys.py
+++ b/pyEPR/ansys.py
@@ -41,21 +41,22 @@
 try:
     import pythoncom
 except (ImportError, ModuleNotFoundError):
-    pass
+    pass #raise NameError ("pythoncom module not installed. Please install.")
 
 try:
     # TODO: Replace `win32com` with Linux compatible package.
     # See Ansys python files in IronPython internal.
     from win32com.client import Dispatch, CDispatch
 except (ImportError, ModuleNotFoundError):
-    pass
+    pass #raise NameError ("win32com module not installed. Please install.")
 
 try:
     from pint import UnitRegistry
     ureg = UnitRegistry()
     Q = ureg.Quantity
 except (ImportError, ModuleNotFoundError):
-    ureg = "Pint module not installed. Please install."
+    pass # raise NameError ("Pint module not installed. Please install.")
+
 
 ##############################################################################
 ###
@@ -2936,6 +2937,30 @@ def getQty(self, name):
     def integrate_line(self, name):
         return self._integrate(name, "EnterLine")
 
+    def normal2surface(self, name):
+        ''' return the part normal to surface.
+            Complex Vector. '''
+        stack = self.stack + [("EnterSurf", name),
+                                ("CalcOp",    "Normal")]
+        stack.append(("CalcOp", "Dot"))
+        stack.append(("EnterSurf", name))
+        stack.append(("CalcOp",    "Normal"))
+        stack.append(("CalcOp", "*"))
+        return CalcObject(stack, self.setup)
+
+    def tangent2surface(self, name):
+        ''' return the part tangent to surface.
+            Complex Vector. '''
+        stack = self.stack + [("EnterSurf", name),
+                                ("CalcOp",    "Normal")]
+        stack.append(("CalcOp", "Dot"))
+        stack.append(("EnterSurf", name))
+        stack.append(("CalcOp",    "Normal"))
+        stack.append(("CalcOp", "*"))
+        stack = self.stack + stack
+        stack.append(("CalcOp", "-"))
+        return CalcObject(stack, self.setup)
+
     def integrate_line_tangent(self, name):
         ''' integrate line tangent to vector expression \n
             name = of line to integrate over '''
diff --git a/pyEPR/core_distributed_analysis.py b/pyEPR/core_distributed_analysis.py
index eb53d34..ed09215 100644
--- a/pyEPR/core_distributed_analysis.py
+++ b/pyEPR/core_distributed_analysis.py
@@ -151,14 +151,14 @@ def __init__(self, *args, **kwargs):
         # Modes and variations - the following get updated in update_variation_information
         self.n_modes = int(1)  # : Number of eigenmodes
         self.modes = None
-        #: List of variation indecies, which are strings of ints, such as ['0', '1']
+        #: List of variation indices, which are strings of ints, such as ['0', '1']
         self.variations = []
-        self.variations_analyzed = []  # : List of analyzed variations. List of indecies
+        self.variations_analyzed = []  # : List of analyzed variations. List of indices
 
         # String identifier of variables, such as  "Cj='2fF' Lj='12.5nH'"
         self._nominal_variation = ''
         self._list_variations = ("",)  # tuple set of variables
-        # container for eBBQ list of varibles; basically the same as _list_variations
+        # container for eBBQ list of variables; basically the same as _list_variations
         self._hfss_variables = Dict()
 
         self._previously_analyzed = set()  # previously analyzed variations
@@ -356,7 +356,6 @@ def _get_lv(self, variation=None):
 
                 ['Lj1:=','13nH', 'QubitGap:=','100um']
         '''
-
         if variation is None:
             lv = self._nominal_variation  # "Cj='2fF' Lj='12.5nH'"
             lv = self._parse_listvariations(lv)
@@ -369,7 +368,7 @@ def _get_lv(self, variation=None):
 
     @property
     def n_variations(self):
-        """ Number of **solved** variaitons, corresponding to the
+        """ Number of **solved** variations, corresponding to the
         selected Setup. """
         return len(self._list_variations)
 
@@ -477,7 +476,6 @@ def update_ansys_info(self):
             n_modes, _list_variations, nominal_variation, n_variations
 
         '''
-
         # from oDesign
         self._nominal_variation = self.design.get_nominal_variation()
 
@@ -888,7 +886,7 @@ def get_Qdielectric(self, dielectric, mode, variation, U_E=None):
 
     def get_Qsurface_all(self, mode, variation, U_E=None):
         '''
-        caculate the contribution to Q of a dieletric layer of dirt on all surfaces
+        calculate the contribution to Q of a dielectric layer of dirt on all surfaces
         set the dirt thickness and loss tangent in the config file
         ref: http://arxiv.org/pdf/1509.01854.pdf
         '''
@@ -1027,10 +1025,10 @@ def calc_p_junction(self, variation, U_H, U_E, Ljs, Cjs):
             #print('\tV_peak=', V_peak)
 
         # ------------------------------------------------------------
-        # Calcualte participations from the peak voltage and currents
+        # Calculate participation from the peak voltage and currents
         #
 
-        # All junction capactive and inductive lumped energies - all peak
+        # All junction capacitive and inductive lumped energies - all peak
         U_J_inds = {j_name: 0.5*Ljs[j_name] * I_peak_[j_name]
                     ** 2 for j_name in self.pinfo.junctions}
         U_J_caps = {j_name: 0.5*Cjs[j_name] * V_peak_[j_name]
@@ -1423,7 +1421,7 @@ def save(self, project_info: dict = None):
             pickle.dump(to_save, handle)  # , protocol=pickle.HIGHEST_PROTOCOL)
 
     def load(self, filepath=None):
-        """Utility function to load reuslts file
+        """Utility function to load results file
 
         Keyword Arguments:
             filepath {[type]} -- [description] (default: {None})
diff --git a/pyEPR/core_quantum_analysis.py b/pyEPR/core_quantum_analysis.py
index 4d8e6fd..541d7d4 100644
--- a/pyEPR/core_quantum_analysis.py
+++ b/pyEPR/core_quantum_analysis.py
@@ -445,7 +445,7 @@ def analyze_all_variations(self,
 
         Specific params:
         --------------------
-            variations : None returns all_variations otherwis this is a list with number
+            variations : None returns all_variations otherwise this is a list with number
                          as strings ['0', '1']
             nalyze_previous :set to true if you wish to overwrite previous analysis
         '''