Friday, August 1, 2014

Python Code for Quadratic Equation

Writing code to find roots of Quadratic equation was a famous assignment when I was learning GW-BASIC and Borland Turbo C. Recently, I have written following Python code. The output of two sample executions are pasted below as well.


# Quadratic equation with real and non-real roots
# Written by Dr. Tariq Javid as of 31 July 2014

a = raw_input('enter a: ')
b = raw_input('enter b: ')
c = raw_input('enter c: ')

a, b, c = int(a), int(b), int(c)

if ((b ** 2) < (4 * a * c)):
    a, b, c = complex(a), complex(b), complex(c)
    x1 = ((-b) + ((b ** 2) - 4 * a * c) ** (0.5)) / (2 * a)
    x2 = ((-b) - ((b ** 2) - 4 * a * c) ** (0.5)) / (2 * a)
    print 'imaginary roots:'
    print x1
    print x2
else:
    a, b, c = float(a), float(b), float(c)
    x1 = ((-b) + ((b ** 2) - 4 * a * c) ** (0.5)) / (2 * a)
    x2 = ((-b) - ((b ** 2) - 4 * a * c) ** (0.5)) / (2 * a)
    print 'real roots:'
    print x1
    print x2