Problem with the command solve in matrices

1 次查看（过去 30 天）

显示更早的评论

Nuno 2013-5-1

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/74237-problem-with-the-command-solve-in-matrices

Problem:

syms w;

D=sym('D', [4 n])

Z1=Z*D(:,1)

F3=ones(4,1)

V=solve(Z1==(1/(m*w^2-i*w*c))*F3,D(:,1))

%m and c are constants; Z is a matrix 4x4 with the variable w in it; n=constant.

My objective is getting the values of D(:,1), i.e., getting D1_1, D2_1, D3_1 and D4_1, but with that formulation I'm getting a message "Warning: Explicit solution could not be found.", and I'm not able to resolve it.

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Nuno 2013-5-7

在 MATLAB Online 中打开

I forgot that the Z matrix has not one, but two variables, y1 and w, for n=3 (for example).

Where, y(1,n)=sym(['y',num2str(n)]);

And Z =

   [1,1,0,0]
   [0,0,-1,-1]
   [exp((30650000^(1/2)*((w^4)^(1/2) + w^2)^(1/2)*308151*i)/766250000)*exp((308151*(30650000*(w^4)^(1/2) - 30650000*w^2)^(1/2))/766250000), exp(-(30650000^(1/2)*((w^4)^(1/2) + w^2)^(1/2)*308151*i)/766250000)*exp(-(308151*(30650000*(w^4)^(1/2) - 30650000*w^2)^(1/2))/766250000), y1*exp((30650000^(1/2)*((w^4)^(1/2) + w^2)^(1/2)*308151*i)/766250000)*exp((308151*30650000^(1/2)*((w^4)^(1/2) - w^2)^(1/2))/766250000), y1*exp(-(30650000^(1/2)*((w^4)^(1/2) + w^2)^(1/2)*308151*i)/766250000)*exp(-(308151*30650000^(1/2)*((w^4)^(1/2) - w^2)^(1/2))/766250000)]
   [y1*exp((30650000^(1/2)*((w^4)^(1/2) + w^2)^(1/2)*308151*i)/766250000)*exp((308151*30650000^(1/2)*((w^4)^(1/2) - w^2)^(1/2))/766250000), y1*exp(-(30650000^(1/2)*((w^4)^(1/2) + w^2)^(1/2)*308151*i)/766250000)*exp(-(308151*30650000^(1/2)*((w^4)^(1/2) - w^2)^(1/2))/766250000),   -exp((30650000^(1/2)*((w^4)^(1/2) + w^2)^(1/2)*308151*i)/766250000)*exp((308151*30650000^(1/2)*((w^4)^(1/2) - w^2)^(1/2))/766250000),   -exp(-(30650000^(1/2)*((w^4)^(1/2) + w^2)^(1/2)*308151*i)/766250000)*exp(-(308151*30650000^(1/2)*((w^4)^(1/2) - w^2)^(1/2))/766250000)]

Sorry for my mistake.

请先登录，再进行评论。

请先登录，再回答此问题。