hello, i want to set the final values of the first function with variable "u" as an initial values for the second function with variable "uc", which can be shown below. my main problem is this term "uc0 = u[end end end end];" what is the correct way.

close all; clc

kd = 10;
cd = 0.0051;
ct = 10.47;
Tt = 39.5671;
Jt = 13.92;
Jb = 1.1378;
WOB = 1760.9718;
Ls = 0.00597;
Lk = 0.0045;
Ld = 0.183;
Lstr = 0.000019312;

u0 = [0 0 0 0];
tspan = [0 45];

[t,u] = ode45(@(t,u) first_order2(u,kd,cd,ct,Tt,Jt,Jb,WOB,Ls,Lk,Ld,Lstr), tspan, u0);

plot(t,u(:,2),'r',t,u(:,4),'b')
figure
plot(u(:,3)-u(:,1),u(:,4),'g')

%CONTROL

uc0 = u[end end end end];

[tc,uc] = ode45(@(tc,uc) control(uc,kd,cd,ct,Tt,Jt,Jb,WOB,Ls,Lk,Ld,Lstr), tspan, uc0);

plot(t,uc(:,2),'r',t,uc(:,4),'b')
figure
plot(uc(:,3)-uc(:,1),uc(:,4),'g')

Answer 1

[Torsten]

uc0 = u(end,:);

[Dirar Aletan]

thanks, i did that but now i got this problem "Index exceeds matrix dimensions. Error in control (line 11) Tst = cd * (uc(2) - uc(4)) + kd * (uc(1) - uc(3)); " for the following function :

function duc = control(tc,uc,kd,cd,ct,Jt,Jb,WOB,Ls,Lk,Ld,Lstr,L,wd)

% u(1) = ot; u(2) = wt; u(3) = ob; u(4) = wb

%R = 0.0492; %dc = 3.7186;

Tst = cd * (uc(2) - uc(4)) + kd * (uc(1) - uc(3)); Tcf = (2/3) * Ls * WOB;

%if u(4) * Ld <= 0.3 % fun = @(r) 2 * WOB / R^2 * (r.^2. * ((Lk/R) + ((Ls/R) - (Lk/R))*exp(-dc*u(4)*r))); % Tdr = integral(fun,0,R); %else Tdr = ((2/3) * Lk * WOB) + (2 * WOB * (Ls - Lk) / (Ld^3 * uc(4)^3)) * (2 - exp(-Ld*uc(4)) * (Ld^2 * uc(4)^2 + 2 * Ld * uc(4) + 2)) + (0.5 * WOB * Lstr * uc(4)); %end

if abs(uc(4)) <= 0.001 && Tst < Tcf Tb = sign(uc(4))*Tst; elseif abs(uc(4)) <= 0.001 && Tst >= Tcf Tb = sign(uc(4))*Tcf; elseif abs(uc(4)) > 0.001 Tb = sign(uc(4))*Tdr; end

% control sys

Tti = (cd + ct) * uc(2) - cd * uc(4) + Kd * (uc(1) - uc(3)) - Jt * L * (uc(2) - wd) - Jt * L (uc(2)-uc(4));

duc = zeros(4,1);

duc(1) = uc(2); duc(2) =(-(cd + ct) * uc(2) + cd * uc(4) - kd * uc(1) + kd * uc(3) + Tti) / Jt; duc(3) = uc(4); duc(4) = (cd * uc(2) - cd * uc(4) + kd * uc(1) - kd * uc(3) - Tb) / Jb; end

[Torsten]

The parameter lists for "control" do not fit:

[tc,uc] = ode45(@(tc,uc) control(uc,kd,cd,ct,Tt,Jt,Jb,WOB,Ls,Lk,Ld,Lstr), tspan, uc0);

gives 12 arguments

function duc = control(tc,uc,kd,cd,ct,Jt,Jb,WOB,Ls,Lk,Ld,Lstr,L,wd)

gives 14 arguments.

[Stephen23]

@Dirar Aletan: rather than trying to pass so many individual variables, I would recommend that you define those values as fields of one structure. Then you just have one variable to pass around.