Initial revision

Demo/classes/Vec.py

@@ -0,0 +1,65 @@
+# A simple vector class
+
+
+def vec(*v):
+	return apply(Vec().init, v)
+
+
+class Vec:
+
+	def init(self, *v):
+		self.v = []
+		for x in v:
+			self.v.append(x)
+		return self
+
+
+	def fromlist(self, v):
+		self.v = []
+		if type(v) <> type([]):
+			raise TypeError
+		self.v = v[:]
+		return self
+
+
+	def __repr__(self):
+		return 'vec(' + `self.v`[1:-1] + ')'
+
+	def __len__(self):
+		return len(self.v)
+
+	def __getitem__(self, i):
+		return self.v[i]
+
+	def __add__(a, b):
+		# Element-wise addition
+		v = []
+		for i in range(len(a)):
+			v.append(a[i] + b[i])
+		return Vec().fromlist(v)
+
+	def __sub__(a, b):
+		# Element-wise subtraction
+		v = []
+		for i in range(len(a)):
+			v.append(a[i] - b[i])
+		return Vec().fromlist(v)
+
+	def __mul__(self, scalar):
+		# Multiply by scalar
+		v = []
+		for i in range(len(self.v)):
+			v.append(self.v[i]*scalar)
+		return Vec().fromlist(v)
+
+
+
+def test():
+	a = vec(1, 2, 3)
+	b = vec(3, 2, 1)
+	print a
+	print b
+	print a+b
+	print a*3.0
+
+test()