第3章_解线性方程组的迭代法_962109547(15)
时间:2025-06-09
时间:2025-06-09
hao
10 A 1
1
110 1
2
2 5
,
72
b 83
42
解 Jacobi迭代 x1
(k 1)
110
1
(72 x
k(
2
)
x2
k
3
(
)
)
x2
(k 1)
x3
(k 1)
101(k)(k) (42 x1 x2) 5
(83 x1
(k)
2x3)
(k)
k01
x1
(k)
x2
(k)
x3
(k)
07.2
08.3
08.4
89
10.998110.9994
11.994111.9994
12.997812.9992
Gauss-Seidel
x1
(k 1)
1101
(72 x2(83 x1
(k)
2x3) 2x3)
(k)
(k)
x2x3
(k 1)(k 1)
(k 1)
101(k 1)(k 1) (42 x1 x2) 5
k01
x1
(k)
x2
(k)
x3
(k)
07.2
09.02
011.644
610.999911.999913.0000
数值结果看出。二个方法均收敛。事实上A为严格对角占优。 此外,Gauss-Seidel迭代比Jacobi迭代收敛更快。 (V)迭代法收敛速度 Ax b
x
(k 1)
(k)
x Bx f
Bx f
(B) 1,任取 x
(0)
R,
n
limx
k
(k)
x,
*
x Bx f
**