Error message: Index exceeds the number of array elements. Index must not exceed 1. When I use trim function

% Define the trim condition
Y0 = 2500; % RPM
X0 = [2500; 0; 0; 0]; % Initial guess for the state vector
U0 = 0; % Input value for trimming
% Perform the trimming
[X0, U0] = trim(model,X0,U0,[],[],Y0);

Unrecognized function or variable 'model'.

The above is my code. Unfortunately, I can't provide the model. The Simulink Model have one input and Three output. But two of three output connects to the Terminator Block.

[Walter Roberson]

Please query,

which trim

At the moment that error is consistent with the possibility that trim is a variable at that point in the code.

[Changyu]

After I run this. C:\Program Files\MATLAB\R2023a\toolbox\simulink\core\general\trim.p

Is .p means this file is a variable?

[Walter Roberson]

No, that would be a function.

Answer 1

[Walter Roberson]

According to trim y0 must be immediately after u0

[Changyu]

[X0, U0] = trim(model,X0,U0,Y0,[],[],Y0);

Although, I add it. It has same erro:Index exceeds the number of array elements. Index must not exceed 1.

Error in trim

Error in trim

[Walter Roberson]

[x,u,y,dx] = trim('sys',x0,u0,y0,ix,iu,iy) finds the trim point closest to x0, u0, y0 that satisfies a specified set of state, input, and/or output conditions. The integer vectors ix, iu, and iy select the values in x0, u0, and y0 that must be satisfied.

You are passing Y0 in the iy position, and Y0 = 2500 in your code. That tells trim() that the 2500'th y0 value must be satisfied. But you only have one y0 value, which is the scalar Y0.

The iy is an index not a value .

You should probably just be using

[X0, U0] = trim(model,X0,U0,Y0);

[Changyu]

Warning: Rank deficient, rank = 1, tol = 1.332268e-15.

> In qpsub

In nlconst

In simcnstr

In trim

In trim

Maximum number of function evaluations exceeded;

increase OPTIONS(14)

It doesn't work. I can't understand the error message.