From 30cf24c84661ac409ca48fb548f57d7affdd4cb6 Mon Sep 17 00:00:00 2001
From: lane <ltdouthit@email.arizona.edu>
Date: Tue, 20 Feb 2018 17:39:45 -0700
Subject: [PATCH] added quadrature trapezoidal rule to Maths

---
 Maths/TrapezoidalRule.py | 45 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)
 create mode 100644 Maths/TrapezoidalRule.py

diff --git a/Maths/TrapezoidalRule.py b/Maths/TrapezoidalRule.py
new file mode 100644
index 000000000..f926ed256
--- /dev/null
+++ b/Maths/TrapezoidalRule.py
@@ -0,0 +1,45 @@
+'''
+Numerical integration or quadrature for a smooth function f with known values at x_i
+
+This method is the classical approch of suming 'Equally Spaced Abscissas' 
+
+method 1: 
+"extended trapezoidal rule"
+
+'''
+
+def method_1(boundary, steps):
+# "extended trapezoidal rule"
+# int(f) = dx/2 * (f1 + 2f2 + ... + fn)
+	h = (boundary[1] - boundary[0]) / steps
+	a = boundary[0]
+	b = boundary[1]
+	x_i = makePoints(a,b,h)
+	y = 0.0	
+	y += (h/2.0)*f(a)
+	for i in x_i:
+		#print(i)	
+		y += h*f(i)
+	y += (h/2.0)*f(b)	
+	return y	
+
+def makePoints(a,b,h):
+	x = a + h	
+	while x < (b-h):
+		yield x
+		x = x + h
+		
+def f(x):
+	y = (x-0)*(x-0)
+	return y
+
+def main():
+	a = 0.0 #Lower bound of integration
+	b = 1.0	#Upper bound of integration
+	steps = 10.0		#define number of steps or resolution	
+	boundary = [a, b]	#define boundary of integration
+	y = method_1(boundary, steps)
+	print 'y = {0}'.format(y)
+
+if __name__ == '__main__':
+	main()