清空筛选条件
清空筛选条件

Array indices must be positive integers or logical values MATLAB error

1 次查看（过去 30 天）
Lucas Larese De Santo
评论： Lucas Larese De Santo 2020-5-10
Why do I keep getting an error "Array indices must be positive integers or logical values"?
m1=100; m2=50; k1=7410; k2=8230; b1=1430; b2=153;
A=[0 1 0 0;
-(k1+k2)/m1 -(b1+b2)/m1 k2/m1 b2/m1;
0 0 0 1;
k2/m2 b2/m2 -k2/m2 -b2/m2];
B=[0 0;
k1/m1 b1/m1
0 0;
0 0];
C=[1 0 0 0;
0 0 1 0;
k1/m1 b1/m1 0 0;
-k2/m2 -b2/m2 k2/m2 b2/m2];
D=[0 0;
0 0
k1/m1 b1/m1
0 0];
h0=0.05;
t0=1;
w=2*pi/t0;
t=0:0.01:4;
z0=h0*sin(w*t).*(0<=t & t<t0)
z0dot=h0*w*cos(w*t).*(0<=t & t<t0);
sys=ss(A,B,C,D);
lsim(sys,z0(t),t)

请先登录，再回答此问题。

回答（1 个）

Toder
Toder 2020-5-10
z0(t) is causing the error. t is a vector of decimals, and you cannot use a decimal as an index. Indices must be positive integers, or logical values, as the error mentions.
  3 个评论
显示 1更早的评论
Walter Roberson
Walter Roberson 2020-5-10
My z0 is a 1x401 double
No, your sys has 2 inputs and 4 outputs, and 401 time points, so your z0 should be 401 x 2 . You should not be replmat() your existing z0: you should be defining pairs of inputs that you want the output state to be calculated for.
Lucas Larese De Santo
Lucas Larese De Santo 2020-5-10
Ok thank you. So what I could thereotically do is for my input for the lsim use [z0;z0dot] then? You also mention z0 should be a 401 x 2, why is that instead of a 2 x 401?

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Passivity and Sector Bounds 的更多信息

标签

产品

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by