列主元消元法python
时间: 2023-11-06 10:02:31 浏览: 83
基于Python的列主元消元法是一种解决nxn阶行列式问题的算法。这个算法的思想是,在每次消元之前,选择未知数系数中绝对值最大的系数作为主元,并通过方程对换将其移到对角线上,然后进行消元。下面是一个用Python实现列主元消元法的示例代码:
```python
import numpy as np
def solve_eq(A,a):
if a.shape[0] != a.shape[1]:
print('系数矩阵不是方阵')
sys.exit(0)
n = A.shape[0]
for i in range(n-1):
max_ = 0
for j in range(i, n):
if np.abs(A[j, i]) > max_:
max_ = np.abs(A[j, i])
maxn = j
exchange = A[i].copy()
A[i] = A[maxn]
A[maxn] = exchange
for k in range(i+1, n):
q = A[k, i] / A[i, i]
A[k, :] = A[k, :] - q * A[i, :]
b = A[:, n]
b[n-1] = A[n-1, n] / A[n-1, n-1]
for i in range(n-2, -1, -1):
b[i] = (b[i] - np.dot(A[i, i+1:n], b[i+1:n])) / A[i, i]
return b
a = np.array([[0.001, 2, 3], [-1, 3.712, 4.623], [-2, 1.072, 5.643]])
c = np.array([1.0, 2.0, 3.0])
A = np.insert(a, 3, values=c, axis=1)
X = solve_eq(A, a)
print(X)
```
请注意,这只是一个简单的示例代码,可以根据实际需求进行修改和优化。
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