我正试图用sympy来解决方程，但我想得到一个直接的数字答案 . 我的脚本是这样的：
from sympy import *
A,B,V=symbols('A,B,V')
eq1=Eq(630.26*(V-39.0)*V*(V+39)-A+B,0)
eq2=Eq(B,1.36*10**8*(V-39))
eq3=Eq(A,5.75*10**5*V*(V+39.0))
solve([eq1,eq2,eq3], [A,B,V], dict=True)
它为我提供了一长串非常扩展的解决方案 . 举个例子，
[{V: 304.107299632956 - (-5162698.06009073 + 3004043.12120894*I)**(1/3)*(-0.5 + 0.866025403784439*I) - 32920.4469842867/((-5162698.06009073 + 3004043.12120894*I)**(1/3)*(-0.5 + 0.866025403784439*I)), B: 36054592750.082 - 1245.8292864816*I*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3) + 8.46536389385714e+17/((-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3)*(1.0 - 1.73205080756888*I)) + 719.279873914469*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3), A: 97854838797.9765 - 3957.60119254414*I*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3) - 3.13901978017549e-5*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(2/3) - 0.000285202926135405*I*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(2/3) + 2925.78725273524*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3)}, {V: 304.107299632956 - (-5162698.06009073 + 3004043.12120894*I)**(1/3) - 32920.4469842867/(-5162698.06009073 + 3004043.12120894*I)**(1/3), B: -1.05776452046245e-5*(4.0015351858068e+22 - 136000000.0*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3)*(25062979.0 - (-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3)))/(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3), A: 97854838797.9765 - 3936.45368131564*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3) + 5.56956529342379e+24/(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(2/3) + 6.43347823930771e-5*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(2/3) - 1.15822484655024e+18/(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3)}, {V: 304.107299632956 - 32920.4469842867/((-5162698.06009073 + 3004043.12120894*I)**(1/3)*(-0.5 - 0.866025403784439*I)) - (-5162698.06009073 + 3004043.12120894*I)**(1/3)*(-0.5 - 0.866025403784439*I), B: 36054592750.082 + 8.46536389385714e+17/((-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3)*(1.0 + 1.73205080756888*I)) + 719.279873914469*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3) + 1245.8292864816*I*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3), A: 97854838797.9765 + 2.31644969310047e+18/((-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3)*(1.0 + 1.73205080756888*I)) - 3.21673911965385e-5*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(2/3) + 5.57155558993486e-5*I*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(2/3) - 1.11391305868476e+25/((-4.36224183723014e+21 + 2.53827793755398e+21*I)**(2/3)*(1.0 - 1.73205080756888*I)) + 1968.22684065782*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3) + 3409.06888884012*I*(-4.36224183723014e+21 + 2.53827793755398e+21*I)**(1/3)}]
我当然可以用evalf评估它们，但不是一次性评估它们 . 我正在寻找一种干净的方式，以数字形式接收方程的解 . 我现在已经做了一个解决方法 . 如果有更好的方法，我真的很想知道 . 我打印答案的功能如下：
def printeqsolve(input):
for i in input:
for j in i:
print "%r:" %j, i[j].evalf(chop=True)
print "---"
我还想排除非真实的解决方案，但是当我将符号限制为Real时，找不到解决方案 .
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