Fix for add_mesh + made stability check optional

Examples/Circular Bin with Conical Hopper.py

@@ -39,10 +39,12 @@
 
 # Add the two meshes to the model
 model.add_mesh(hopper_mesh)
+
+import cProfile
+# cProfile.run('model.add_mesh(shell_mesh)', sort='cumtime')
 model.add_mesh(shell_mesh)
 
 # The two meshes have overlapping duplicate nodes that need to be merged
-import cProfile
 # cProfile.run('model.merge_duplicate_nodes()', sort='cumtime')
 model.merge_duplicate_nodes()
 
@@ -60,8 +62,8 @@
 model.add_load_combo('1.4F', {'Hydrostatic': 1.4})
 
 # Analyze the model
-# cProfile.run('model.analyze()', sort='cumtime')
-model.analyze()
+cProfile.run('model.analyze()', sort='cumtime')
+# model.analyze()
 
 # Render the model. Labels and loads will be turned off to speed up interaction.
 render_model(model, 0.1, render_loads=True, color_map='dz', combo_name='1.4F', labels=False)

PyNite/FEModel3D.py

@@ -403,7 +403,7 @@ def add_mesh(self, mesh, rename=True):
                 self.Nodes[node.Name] = node
             else:
                 # Get the next available node name and rename the node
-                new_name = 'N' + str(len(self.Nodes))
+                new_name = 'N' + str(len(self.Nodes + 1))
                 node.Name = new_name
                 self.Nodes[new_name] = node
 
@@ -422,7 +422,7 @@ def add_mesh(self, mesh, rename=True):
                     self.Plates[element.Name] = element
                 else:
                     # Get the next available element name and rename the element
-                    new_name = 'P' + str(len(self.Plates))
+                    new_name = 'P' + str(len(self.Plates + 1))
                     element.Name = new_name
                     self.Plates[new_name] = element
 
@@ -434,7 +434,7 @@ def add_mesh(self, mesh, rename=True):
                     self.Quads[element.Name] = element
                 else:
                     # Get the next available element name and rename the element
-                    new_name = 'Q' + str(len(self.Quads))
+                    new_name = 'Q' + str(len(self.Quads + 1))
                     element.Name = new_name
                     self.Quads[new_name] = element
 
@@ -1136,7 +1136,7 @@ def _aux_list(self):
         # Return the indices and the known displacements
         return D1_indices, D2_indices, D2
 
-    def K(self, combo_name='Combo 1', log=False, sparse=True):
+    def K(self, combo_name='Combo 1', log=False, check_stability=True, sparse=True):
         """
         Returns the model's global stiffness matrix.
 
@@ -1447,9 +1447,10 @@ def K(self, combo_name='Combo 1', log=False, sparse=True):
             K = coo_matrix((data, (row, col)), shape=(len(self.Nodes)*6, len(self.Nodes)*6))
 
         # Check that there are no nodal instabilities
-        if log: print('- Checking nodal stability')
-        if sparse: self._check_stability(K.tocsr())
-        else: self._check_stability(K)
+        if check_stability:
+            if log: print('- Checking nodal stability')
+            if sparse: self._check_stability(K.tocsr())
+            else: self._check_stability(K)
 
         # Return the global stiffness matrix
         return K      
@@ -1721,7 +1722,7 @@ def _partition(self, unp_matrix, D1_indices, D2_indices):
             m22 = unp_matrix[D2_indices, :][:, D2_indices]
             return m11, m12, m21, m22
 
-    def analyze(self, log=False, check_statics=False, max_iter=30, sparse=True):
+    def analyze(self, log=False, check_stability=True, check_statics=False, max_iter=30, sparse=True):
         '''
         Performs first-order static analysis.
         
@@ -1795,9 +1796,9 @@ def analyze(self, log=False, check_statics=False, max_iter=30, sparse=True):
 
                 # Get the partitioned global stiffness matrix K11, K12, K21, K22
                 if sparse == True:
-                    K11, K12, K21, K22 = self._partition(self.K(combo.name, log, sparse).tolil(), D1_indices, D2_indices)
+                    K11, K12, K21, K22 = self._partition(self.K(combo.name, log, check_stability, sparse).tolil(), D1_indices, D2_indices)
                 else:
-                    K11, K12, K21, K22 = self._partition(self.K(combo.name, log, sparse), D1_indices, D2_indices)
+                    K11, K12, K21, K22 = self._partition(self.K(combo.name, log, check_stability, sparse), D1_indices, D2_indices)
 
                 # Get the partitioned global fixed end reaction vector
                 FER1, FER2 = self._partition(self.FER(combo.name), D1_indices, D2_indices)
@@ -1976,7 +1977,7 @@ def analyze(self, log=False, check_statics=False, max_iter=30, sparse=True):
         if check_statics == True:
             self._check_statics()
 
-    def analyze_PDelta(self, log=False, max_iter=30, tol=0.01, sparse=True):
+    def analyze_PDelta(self, log=False, check_stability=True, max_iter=30, tol=0.01, sparse=True):
         '''
         Performs second order (P-Delta) analysis.
 
@@ -2063,9 +2064,9 @@ def analyze_PDelta(self, log=False, max_iter=30, tol=0.01, sparse=True):
                 if iter_count_PD == 1:
 
                     if sparse == True:
-                        K11, K12, K21, K22 = self._partition(self.K(combo.name, log, sparse).tolil(), D1_indices, D2_indices)  # Initial stiffness matrix
+                        K11, K12, K21, K22 = self._partition(self.K(combo.name, log, check_stability, sparse).tolil(), D1_indices, D2_indices)  # Initial stiffness matrix
                     else:
-                        K11, K12, K21, K22 = self._partition(self.K(combo.name, log, sparse), D1_indices, D2_indices)  # Initial stiffness matrix
+                        K11, K12, K21, K22 = self._partition(self.K(combo.name, log, check_stability, sparse), D1_indices, D2_indices)  # Initial stiffness matrix
 
                     # Check that the structure is stable
                     if log: print('- Checking stability')
@@ -2082,7 +2083,7 @@ def analyze_PDelta(self, log=False, max_iter=30, tol=0.01, sparse=True):
                     # Calculate the partitioned global stiffness matrices
                     if sparse == True:
 
-                        K11, K12, K21, K22 = self._partition(self.K(combo.name, log, sparse).tolil(), D1_indices, D2_indices)  # Initial stiffness matrix
+                        K11, K12, K21, K22 = self._partition(self.K(combo.name, log, check_stability, sparse).tolil(), D1_indices, D2_indices)  # Initial stiffness matrix
                         Kg11, Kg12, Kg21, Kg22 = self._partition(self.Kg(combo.name, log, sparse), D1_indices, D2_indices)     # Geometric stiffness matrix
 
                         # The stiffness matrices are currently `lil` format which is great for
@@ -2096,7 +2097,7 @@ def analyze_PDelta(self, log=False, max_iter=30, tol=0.01, sparse=True):
 
                     else:
 
-                        K11, K12, K21, K22 = self._partition(self.K(combo.name, log, sparse), D1_indices, D2_indices)       # Initial stiffness matrix
+                        K11, K12, K21, K22 = self._partition(self.K(combo.name, log, check_stability, sparse), D1_indices, D2_indices)       # Initial stiffness matrix
                         Kg11, Kg12, Kg21, Kg22 = self._partition(self.Kg(combo.name, log, sparse), D1_indices, D2_indices)  # Geometric stiffness matrix
 
                         K11 = K11 + Kg11
@@ -2781,24 +2782,49 @@ def rename(self):
         """
 
         # Rename each node in the model
-        for id, node in enumerate(self.Nodes.values()):
-            node.Name = 'N' + str(id)
+        temp = self.Nodes.copy()
+        id = 1
+        for old_key, node in temp.items():
+            new_key = 'N' + str(id)
+            self.Nodes[new_key] = self.Nodes.pop(old_key)
+            self.Nodes[new_key].Name = new_key
+            id += 1
 
         # Rename each spring in the model
-        for id, spring in enumerate(self.Springs.values()):
-            spring.Name = 'S' + str(id)
+        temp = self.Springs.copy()
+        id = 1
+        for old_key, spring in temp.items():
+            new_key = 'S' + str(id)
+            self.Springs[new_key] = self.Springs.pop(old_key)
+            self.Springs[new_key].Name = new_key
+            id += 1
 
         # Rename each member in the model
-        for id, member in enumerate(self.Members.values()):
-            member.Name = 'M' + str(id)
+        temp = self.Members.copy()
+        id = 1
+        for old_key, member in temp.items():
+            new_key = 'M' + str(id)
+            self.Members[new_key] = self.Members.pop(old_key)
+            self.Members[new_key].Name = new_key
+            id += 1
 
         # Rename each plate in the model
-        for id, plate in enumerate(self.Plates.values()):
-            plate.Name = 'P' + str(id)
+        temp = self.Plates.copy()
+        id = 1
+        for old_key, plate in temp.items():
+            new_key = 'P' + str(id)
+            self.Plates[new_key] = self.Plates.pop(old_key)
+            self.Plates[new_key].Name = new_key
+            id += 1
 
         # Rename each quad in the model
-        for id, quad in enumerate(self.Quads.values()):
-            quad.Name = 'Q' + str(id)
+        temp = self.Quads.copy()
+        id = 1
+        for old_key, quad in temp.items():
+            new_key = 'Q' + str(id)
+            self.Quads[new_key] = self.Quads.pop(old_key)
+            self.Quads[new_key].Name = new_key
+            id += 1
 
     def orphaned_nodes(self):
         """

README.md

@@ -62,6 +62,10 @@ PyNite depends on the following packages:
 * sympy: Only needed if you want to view the derivations used to build PyNite.
 
 # What's New?
+v0.0.63
+* Fixed the `add_mesh` method. It was not working properly after version 0.0.62.
+* Made stability checks optional. Stability checks add significant solve time. If you are confident your model is stable, you can skip the stability check by toggling `check_stability` to `False` in your call to your analysis command.
+
 v0.0.62
 * PyNite now checks for nodal instabilities when analyzing a model. If nodal instabilities are found, PyNite will output the unstable nodes and directions to the console, and will throw an exception.
 * Added a method called `rename` to the `FEModel3D` class for quickly renaming all the nodes and elements in the model in sequential order.

setup.py

@@ -5,7 +5,7 @@
 
 setuptools.setup(
     name="PyNiteFEA",
-    version="0.0.62",
+    version="0.0.63",
     author="D. Craig Brinck, PE, SE",
     author_email="Building.Code@outlook.com",
     description="A simple elastic 3D structural finite element library for Python.",