Add support to Python 3 with a single codebase

Author: cdsousa

.travis.yml

@@ -1,6 +1,7 @@
 language: python
 python:
   - "2.7"
+  - "3.3"
 before_install:
   - pip install sympy --use-mirrors
   - pip install numpy --use-mirrors
@@ -9,4 +10,4 @@ install:
 before_script:
   - cd sympybotics
 script:
-  - ../run_tests.sh
+  - ../run_tests.sh

sympybotics/_compatibility_.py

@@ -0,0 +1,22 @@
+""" Python 2/3 compatibility utils """
+
+import sys
+pyversion = sys.version_info[0]
+
+# exec (from https://bitbucket.org/gutworth/six/):
+if pyversion is 3:
+    import builtins
+    exec_ = getattr(builtins, "exec")
+    del builtins
+elif pyversion is 2:
+    def exec_(_code_, _globs_=None, _locs_=None):
+        """Execute code in a namespace."""
+        if _globs_ is None:
+            frame = sys._getframe(1)
+            _globs_ = frame.f_globals
+            if _locs_ is None:
+                _locs_ = frame.f_locals
+            del frame
+        elif _locs_ is None:
+            _locs_ = _globs_
+        exec("""exec _code_ in _globs_, _locs_""")

sympybotics/dynamics/regressor.py

@@ -27,8 +27,8 @@ def regressor(rbtdef, geom, ifunc=None):
     for p, parm in enumerate(dynparms):
 
         for i in range(rbtdef.dof):
-            rbtdeftmp.Le[i] = map(
-                lambda x: 1 if x == parm else 0, rbtdef.Le[i])
+            rbtdeftmp.Le[i] = list(map(
+                lambda x: 1 if x == parm else 0, rbtdef.Le[i]))
             rbtdeftmp.l[i] = Matrix(rbtdef.l[i]).applyfunc(
                 lambda x: 1 if x == parm else 0)
             rbtdeftmp.m[i] = 1 if rbtdef.m[i] == parm else 0

sympybotics/robotmodel.py

@@ -6,6 +6,7 @@
 from .kinematics import Kinematics
 from .dynamics import Dynamics
 from .symcode import Subexprs, code_to_func
+from ._compatibility_ import exec_
 
 def _fprint(x):
     print(x)
@@ -99,11 +100,15 @@ def calc_base_parms(self, verbose=False):
         func_def_regressor = code_to_func(
             'python', self.H_code, 'regressor_func', ['q', 'dq', 'ddq'],
             q_subs)
+
         global sin, cos, sign
         sin = numpy.sin
         cos = numpy.cos
         sign = numpy.sign
-        exec(func_def_regressor)
+
+        l = locals()
+        exec_(func_def_regressor, globals(), l)
+        regressor_func = l['regressor_func']
 
         if verbose:
             _fprint('calculating base parameters and regressor code')

sympybotics/symcode/subexprs.py

@@ -170,7 +170,7 @@ def collect(self, exprs):
         prep_exprs = [preprocess_for_cse(e, self._optimizations)
                       for e in exprs]
 
-        out_exprs = map(self._parse, prep_exprs)
+        out_exprs = list(map(self._parse, prep_exprs))
 
         if is_single_expr:
             return out_exprs[0]
@@ -193,7 +193,7 @@ def get(self, exprs=None, symbols=None):
 
         # Find all of the repeated subexpressions.
 
-        ivar_se = {iv: se for se, iv in self._subexp_iv.iteritems()}
+        ivar_se = {iv: se for se, iv in self._subexp_iv.items()}
 
         used_ivs = set()
         repeated = set()

sympybotics/tests/test_results.py

@@ -3,6 +3,10 @@
 from math import cos, sin
 
 import sympybotics
+from sympybotics._compatibility_ import exec_
+
+
+
 
 
 def test_scara_dh_sym_geo_kin():
@@ -121,11 +125,17 @@ def test_puma_dh_num_geo_kin_dyn():
     H_func_def = sympybotics.robotcodegen.dyn_code_to_func(
         'python', puma560.H_code, 'H_puma560', 2, puma560.dof)
 
-    exec(M_func_def)
-    exec(c_func_def)
-    exec(g_func_def)
-    exec(tau_func_def)
-    exec(H_func_def)
+    l = locals()
+    exec_(M_func_def, globals(), l)
+    exec_(c_func_def, globals(), l)
+    exec_(g_func_def, globals(), l)
+    exec_(tau_func_def, globals(), l)
+    exec_(H_func_def, globals(), l)
+    tau_puma560 = l['tau_puma560']
+    g_puma560 = l['g_puma560']
+    c_puma560 = l['c_puma560']
+    M_puma560 = l['M_puma560']
+    H_puma560 = l['H_puma560']
 
     tau = tau_puma560(dynparm_test, q_test, dq_test, ddq_test)
     tau = numpy.matrix(tau).T.astype(numpy.float64)
@@ -307,11 +317,17 @@ def test_puma_mdh_num_geo_kin_dyn():
     H_func_def = sympybotics.robotcodegen.dyn_code_to_func(
         'python', puma560.H_code, 'H_puma560', 2, puma560.dof)
 
-    exec(M_func_def)
-    exec(c_func_def)
-    exec(g_func_def)
-    exec(tau_func_def)
-    exec(H_func_def)
+    l = locals()
+    exec_(M_func_def, globals(), l)
+    exec_(c_func_def, globals(), l)
+    exec_(g_func_def, globals(), l)
+    exec_(tau_func_def, globals(), l)
+    exec_(H_func_def, globals(), l)
+    tau_puma560 = l['tau_puma560']
+    g_puma560 = l['g_puma560']
+    c_puma560 = l['c_puma560']
+    M_puma560 = l['M_puma560']
+    H_puma560 = l['H_puma560']
 
     tau = tau_puma560(dynparm_test, q_test, dq_test, ddq_test)
     tau = numpy.matrix(tau).T.astype(numpy.float64)