Python script to compute definite integral by trapezoidal rule.

definite_ingegral_trapezoid.py

#! /usr/local/bin/python3.6
"""
Definite integral by by trapizoidal rule
"""
import math
import sys
import traceback


class DefiniteIntegralTrapezoid:
    M = 100  # Number of division

    def __init__(self):
        self.f = lambda x: math.sqrt(4 - x * x)

    def compute(self, a, b):
        """
        Computation of infinite intagral
        """
        try:
            h = (b - a) / self.M
            x, s = a, 0
            for k in range(1, self.M):
                x += h
                s += self.f(x)
            s = h * ((self.f(a) + self.f(b)) / 2 + s)
            print("  / {:f}".format(b))
            print("  |  f(x)dx = {:f} ".format(s))
            print("  / {:f}".format(a))
        except Exception as e:
            raise


if __name__ == '__main__':
    if len(sys.argv) < 3:
        print("USAGE: ./definite_integral_trapezoid.py A B")
        sys.exit(0)
    a, b = list(map(float, sys.argv[1:3]))
    if a == 0 and b == 0:
        sys.exit(0)

    try:
        obj = DefiniteIntegralTrapezoid()
        obj.compute(a, b)
    except Exception as e:
        traceback.print_exc()
        sys.exit(1)