用Python解决6个非线性方程组的问题

如何解决用Python解决6个非线性方程组的问题

我正在尝试使用Python解决由6个非线性方程组成的系统。到目前为止，我已经：

from scipy.optimize import fsolve 
import math 
from numpy import log

ka1 = 1.045
ka2 = 0.1759
ka3 = 0.3159

def equations(p):
    yh2o,yco2,yh2,ych4,yco = p

    return (yh2o + yco2 + yh2 + ych4 + yco - 1,ka1 - (yh2o ** 2)/(yco * (yh2 ** 2),ka2 - (yco ** 2) / yco2,ka3 - ych4 / (yh2 ** 2),0.5 - (2.0 * yco2 + yco + yh2o) / (2 * yh2o + 2 * yh2 + 4 * ych4)))

yh2o,yco = fsolve(equations,[0.2,0.2,0.2])

print(f"yh2o = {yh2o},yco2 = {yco2},yh2 = {yh2},ych4 = {ych4},yco = {yco}")

当我尝试运行此命令时，我会得到

TypeError: fsolve: there is a mismatch between the input and output shape of the 'func' argument 'equations'.Shape should be (5,) but it is (2,).

我尝试更改初始猜测，但错误仍然相同。

我还尝试过将等式更改为多项式：

    return (yh2o + yco2 + yh2 + ych4 + yco - 1.0,ka1 * (yco * (yh2 ** 2.0)) - (yh2o * yh2o),ka2 * (yco2) - (yco ** 2.0),ka3 * (yh2 ** 2.0) - ych4,0.5 * (2.0 * yh2o + 2.0 * yh2 + 4 * ych4) - (2.0 * yco2 + yco + yh2o)) 

但是我说错了

TypeError: can't multiply sequence by non-int of type 'float'

解决方法

我认为您在方程式（返回的元组）中括号（即放置(和)）有问题。

下面是完整的经过纠正的工作代码：

Try it online!

from scipy.optimize import fsolve 
import math 
from numpy import log

ka1 = 1.045
ka2 = 0.1759
ka3 = 0.3159

def equations(p):
    yh2o,yco2,yh2,ych4,yco = p

    return (
        (yh2o + yco2 + yh2 + ych4 + yco - 1),ka1 - (yh2o ** 2) / (yco * (yh2 ** 2)),ka2 - (yco ** 2) / yco2,ka3 - ych4 / (yh2 ** 2),0.5 - (2.0 * yco2 + yco + yh2o) / (2 * yh2o + 2 * yh2 + 4 * ych4)
    )

yh2o,yco = fsolve(equations,[0.2,0.2,0.2])

print(f"yh2o = {yh2o},yco2 = {yco2},yh2 = {yh2},ych4 = {ych4},yco = {yco}")

输出：

yh2o = 0.17829101808889491,yco2 = 0.17513942402710805,yh2 = 0.4163023675952086,ych4 = 0.05474789024926531,yco = 0.1755193000395232