计算平方根

[python]代码库

# -*- coding: utf-8 -*-
import math

def quadratic(a1,b1,c1):
    a = int(a1)
    b = int(b1)
    c = int(c1)
    
    if b*b-4*a*c >0 :
        t=b*b-4*a*c
        t2 = math.sqrt(t)
        x1 = -(b/(2*a))+(t2/(2*a))
        x2 = -(b/(2*a))-(t2/(2*a))
        z = 1
        return x1,x2,z
    elif b*b-4*a*c == 0 :
        
        x1 = (-b/(2*a))
        z=0
        return x1,x1,z
    else:
        t=4*a*c-b*b
        t2 = math.sqrt(t)
        x = (-b/(2*a))
        y = (t2/(2*a))
        z = -1
        return x,y,z




a = input('输入ax2+bx+c的a值：')
b = input('输入ax2+bx+c的b值：')
c = input('输入ax2+bx+c的c值：')

x,y,z = quadratic(a,b,c)
if z == 1:
    print('该方程有两个根x1,x2分别为%.3f %.3f'%(x,y))
elif z == 0:
    print('该方程有一个根x1=%.3f'%(x))
else :
    print('该方程有两个虚根a,b分别为%.3f %.3f'%(x,y))