matlab解矩阵微分方程 Matlab如何求解矩阵微分方程组的符号解
matlab \u77e9\u9635\u5fae\u5206\u65b9\u7a0b\u6c42\u89e3\u6700\u5e38\u7528\u7684\u5c31\u662f\u5e7f\u4e49\u7279\u5f81\u5411\u91cf\u57fa\u7840\u77e9\u9635\u89e3\u65b9\u6cd5\u3002\u4f60\u8981\u4e00\u4e2a\u601d\u8def\uff0c\u6211\u7ed9\u4e00\u4e2a2\u7ef4\u60c5\u51b5\u7684\u4f8b\u5b50\uff0c\u5176\u4e2d\u7279\u89e3x(t0)=x0\u7684\u7406\u89e3\u548c\u5982\u4f55\u4f7f\u7528\u90fd\u6709\uff0c\u4f60\u770b\u770b\u662f\u5426\u591f\u7528\u3002
.
Matlab \u4e0b\u4e8c\u7ef4\u7684\u4f8b\u5b50\uff1a
\u4f7f\u7528dsolve\u51fd\u6570
dsolve('Dx=2*c*x+A*y','Dy=g*y','Dz=A*x+A*z','x(0)=0','y(0)=1','z(0)=0')
\u5c31\u662f\u628a\u65b9\u7a0b\u7ec4\u5199\u51fa\u4e09\u4e2a\u5fae\u5206\u65b9\u7a0b\u8fdb\u884c\u8ba1\u7b97
\u795d\u4f60\u5b66\u4e60\u6109\u5feb\uff01
参考代码：
% 参数定义
m1 = 1; m2 = 2; m3 = 3;
k1 = 4; k2 = 5; k3 = 6;
c1 = 7; c2 = 8; c3 = 9;
Qy = 10;
% 微分方程
K = [k1 -k1 0; -k1 k1+k2 -k2; 0 -k2 k2+k3];
C = [c1 -c1 0; -c1 c1+c2 -c2; 0 -c2 c2+c3]
dy = @(t,y)[y(4:6); (-K*y(1:3)-C*y(4:6)+[Qy;0;0])./[m1;m2;m3]];
% 初始条件（y4~y6 为 y1'~y3'）
y0 = zeros(6,1);
% 求解，直接绘图
[t,y] = ode45(dy,[0 15],y0);
plot(t,y(:,1:3));
lstr = arrayfun(@(i){sprintf('y%i',i)},1:3);
legend(lstr{:})
legend(lstr{:},'Location','S','Orientation','horizontal')
忘光了，全还给老师了
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