matlab求矩阵最佳方程
matlab\u5982\u4f55\u89e3\u77e9\u9635\u65b9\u7a0b\uff1f1. \u8bbeAx = b\uff0c\u6c42x\uff0c\uff08x\u548cb\u90fd\u662f\u5411\u91cf\uff09\u5219\uff1ax = A\b
\u5c31\u8fd9\u4e48\u7b80\u5355\u3002\u60f3\u4e0d\u51fa\u66f4\u590d\u6742\u7684\u65b9\u6cd5\u4e86\u3002
2. \u4f60\u4e0a\u9762\u7684\u770b\u8d77\u6765\u662f\u4e2a\u9f50\u6b21\u65b9\u7a0b\uff0c\u4f46\u662f\u56e0\u4e3ab1 b2 b3\u5df2\u77e5\uff0c\u53ef\u4ee5\u79fb\u5230\u7b49\u53f7\u53e6\u4e00\u8fb9\uff1b\u518d\u628aV3=V4\u6574\u7406\u5230\u77e9\u9635\u65b9\u7a0b\u91cc\u6216\u8005\u5e72\u8106\u4ece\u65b9\u7a0b\u4e2d\u53bb\u6389V4\uff0c\u5c31\u53ef\u4ee5\u7528\u4e0a\u9762\u65b9\u6cd5\u89e3\u4e86\u3002
syms y
x=[0 1;2 3]
x =
0 1
2 3
t=inv(x'.*x).*x*y
t =
[ 0, y/2]
[ y, 0]
A=[1
1 ;2,1；3,1；4,1,；5,1];
B=[9.60,8.85,8.05,7.50,7.15];
format
rat
x1=A\B %求得非齐次方程组Ax=B的一个特解x1
Y=null(A,’r’) %求得齐次方程组Ax=0 的基础解系Y
解法二:
formatrat
A=[1 1 ;2,1；3,1；4,1,；5,1];
B=[9.60,8.85,8.05,7.50,7.15]; %用初等行变换将增广矩阵[AB] 化成最简行阶梯形T
T=rref([AB])
绛旓細鍙互鎶0.1绉诲埌绛夊彿鐨勫彸杈癸紝杩欐牱A'=[4.46,-0.54;-1.7,3.3;-3,-3],B'=[0.054;0.17;-0.2],鐒跺悗鍐嶅仛闄ゆ硶銆侫\B灏卞彲浠ヤ簡銆
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