change data, mathematics, function, geometry and geometry_plot_pylab. add data_step, data_step_std and helper. add an example and more documentation.

inside the data module rename read to read_columns add add new read function to read the whole file as string. add print_list function to print one element per line. add unique_list and unique_list_hashable to reduce the list into a unique list with same order. add find_last, str_between, str_to_list functions.

inside the mathematics module for vector add normalized creating a new object (normalize will change the object), isclose and iscloseto, change ang to round internal number. for matrix improve slicing and add transposed creating a new object (transpose will change object).

inside the function module add b_spline_basis, b_spline_curve_with_knots and b_spline_knots functions. add sample_hal_open and sample_half_open_seq. add circle and ellipse.

inside the geometry module change CS init from using lists to Directions and add new constructor CS.init_xzy using lists. rename Wireframe to Polyline. add classes B_spline_curve_with_knots, Ellipse, ArcCircle, ArcEllipse, ArcBSplineCurveWithKnots. add function sample_half_open to create a list of Points.

inside the geometry_plot_pylab module change the help text.

add step_and data data_step_std module to read a step file to list and draw the content.

add helper module with context manager and decorator timeit to meassure the time for a section or function.

add example for b_spline function.

tests/test_mathematics.py

@@ -167,14 +167,42 @@ class TestGeometry(unittest.TestCase):
         len(obj),
         3)
 
-  def test_vector_normalize(self):
-    v = vector.normalize(vector([3, 4]))
+  def test_vector_ang(self):
+    a = vector([1, 0])
+    b = vector([0, 1])
+    print(vector.ang(a,b), vector.ang(b, a))
     self.assertEqual(
-        v,
+      vector.ang(a, b),
+      math.pi/2)
+    self.assertEqual(
+      vector.ang(b, a),
+      math.pi/2)
+
+  def test_vector_normalized(self):
+    v1 = vector([3, 4])
+    v2 = vector.normalized(v1)
+    self.assertEqual(
+        v2,
         [0.6, 0.8])
     self.assertEqual(
-        abs(v),
+        abs(v2),
         1)
+    self.assertEqual(
+        v1,
+        [3, 4])
+
+  def test_vector_normalize(self):
+    v1 = vector([3, 4])
+    v2 = v1.normalize()
+    self.assertEqual(
+        v2,
+        [0.6, 0.8])
+    self.assertEqual(
+        abs(v2),
+        1)
+    self.assertEqual(
+        v1,
+        [0.6, 0.8])
 
   def test_vector_rotate_x(self):
     # rotation of vector coordinate system about x axis