#想用python解方程，三元的，但求解时间太长了，等不出答案。有没有办法限制未知c1，c2，c3的精度，三位或者四位小数就行#
from sympy import *
p1 = 0.981
Ev1=54
p2 = 0.992
Ev2= 67.5
p3 = 0.995
Ev3= 87.5
c1 = Symbol('c1')
c2 = Symbol('c2')
c3 = Symbol('c3')
r = solve([c1*(1-c2*10**(-c3*Ev1))-p1, c1*(1-c2*10**(-c3*Ev2))-p2,c1*(1-c2*10**(-c3*Ev3))-p3],[c1, c2, c3])
print ("[c1, c2, c3] = ",r)
print ("1111")
