用matlab解方程组的问题，五个方程求解四个未知数。 请教：在matlab解方程组中，5个未知数，4个方程的方程组...
matlab\u89e3\u65b9\u7a0b\u7ec4\u95ee\u9898\uff0c\u4e94\u4e2a\u65b9\u7a0b\uff0c\u6709\u56db\u4e2a\u672a\u77e5\u6570\uff0c\u6309\u7167\u4e0b\u9762\u5199\u7684\u89e3\u4e0d\u51fa\u6765\uff0c\u8bf7\u9ad8\u624b\u5e2e\u5fd9\u3002\u6539\u7528\u6570\u503c\u89e3\uff1a
1\u3001\u7f16\u5199\u51fd\u6570\uff1a
function f=fun2(in)
x=in(1);y=in(2);z=in(3);t=in(4);
f(1)=((500-x)^2+(3300-y)^2+z^2)/(21.15-t)^2-((3200-x)^2+(3100-y)^2+z^2)/(17.95-t)^2;
f(2)=((300-x)^2+(200-y)^2+z^2)/(19.4833-t)^2-((3400-x)^2+(100-y)^2+z^2)/(16.8167-t)^2;
f(3)=((800-x)^2+(1600-y)^2+z^2)/(14.85-t)^2-((2500-x)^2+(1900-y)^2+z^2)/(10.2333-t)^2;
f(4)=((1400-x)^2+(2200-y)^2+z^2)/(13.2833-t)^2-((2300-x)^2+(2800-y)^2+z^2)/(14.7833-t)^2;
f(5)=((1700-x)^2+(700-y)^2+z^2)/(11.7667-t)^2-((2900-x)^2+(900-y)^2+z^2)/(11.7667-t)^2;
2\u3001\u8c03\u7528\u6c42\u89e3\uff1a
fsolve(@(x)fun2(x),x0);% x0\u53ef\u4ee5\u6839\u636e\u5b9e\u9645\u786e\u5b9a\u51fa\u5927\u81f4\u8303\u56f4\u5373\u53ef
\u6539\u7528\u6570\u503c\u89e3\uff1a
1\u3001\u7f16\u5199\u51fd\u6570\uff1a
function f=fun2(in)
x=in(1);y=in(2);z=in(3);t=in(4);
f(1)=((500-x)^2+(3300-y)^2+z^2)/(21.15-t)^2-((3200-x)^2+(3100-y)^2+z^2)/(17.95-t)^2;
f(2)=((300-x)^2+(200-y)^2+z^2)/(19.4833-t)^2-((3400-x)^2+(100-y)^2+z^2)/(16.8167-t)^2;
f(3)=((800-x)^2+(1600-y)^2+z^2)/(14.85-t)^2-((2500-x)^2+(1900-y)^2+z^2)/(10.2333-t)^2;
f(4)=((1400-x)^2+(2200-y)^2+z^2)/(13.2833-t)^2-((2300-x)^2+(2800-y)^2+z^2)/(14.7833-t)^2;
f(5)=((1700-x)^2+(700-y)^2+z^2)/(11.7667-t)^2-((2900-x)^2+(900-y)^2+z^2)/(11.7667-t)^2;
2\u3001\u8c03\u7528\u6c42\u89e3\uff1a
fsolve(@(x)fun2(x),x0);% x0\u53ef\u4ee5\u6839\u636e\u5b9e\u9645\u786e\u5b9a\u51fa\u5927\u81f4\u8303\u56f4\u5373\u53ef
clear
c1=10496.108; c2=10500.275; c3=10504.442; c4=10508.609; c5=10512.776;
A=[1,c1,c1^2,c1^3; 1,c2,c2^2,c2^3; 1,c3,c3^2,c3^3; 1,c4,c4^2,c4^3; 1,c5,c5^2,c5^3;];
B=[-3043766.03 ;-3042809.53;-3041787.84;-3040701.05;-3039549.25];
xyzt=pinv(A)*B %伪逆法求解
%xyzt=A\B %左除法
xyzt =
1.0e+004 *
0.0005
1.8316
-0.0004
0.0000
把系数写成矩阵，然后直接用等号右边的矩阵除以系数矩阵，或者直接用solve函数，看看帮助，里面写的很详细
超定方程
可以用fsolve函数求解
有时间的话就帮你做了
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