updated contents from Atlas repo

iterables/vector_flex_init.py

@@ -0,0 +1,43 @@
+"""
+A more flexible `__init__` for the Vector class
+
+A Vector can be built from an iterable:
+
+    >>> Vector([10, 20, 30])
+    Vector(10, 20, 30)
+    >>> Vector(range(1, 5))
+    Vector(1, 2, 3, 4)
+
+Or from two more arguments:
+
+    >>> Vector(100, 200)
+    Vector(100, 200)
+    >>> Vector(1, 2, 3, 4, 5)
+    Vector(1, 2, 3, 4, 5)
+
+One-dimensional vectors are not supported:
+
+    >>> Vector(99)
+    Traceback (most recent call last):
+       ...
+    TypeError: Vector() takes one iterable argument or at least 2 scalar arguments
+
+"""
+
+import reprlib
+
+
+class Vector:
+    """An n-dimensional vector"""
+
+    def __init__(self, first, *rest):  # <1>
+        if rest:
+            self._components = (first,) + tuple(rest)  # <3>
+        else:
+            try:
+                self._components = tuple(first)  # <2>
+            except TypeError:
+                raise TypeError('Vector() takes one iterable argument or at least 2 scalar arguments')
+
+    def __repr__(self):
+        return 'Vector' + reprlib.repr(self._components)