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From: Stephen on 14 Apr 2010 03:32
I am trying to solve a system of 6 ODE's where on the 2nd ODE has a desired final value; however, it is not a BVP. I am trying to include a while loop to adjust the initial value for this equation until the desired tolerance for the final value, eq2(end), is reached. The error I am getting is: 'Index exceeds matrix dimensions.
Error in ==> mars_ascent_vehicle_optimization at 46
while abs(gamma_2{J}(K))>0.01'

Here is my code. The while loop is located below the break.

clear
clc
format short g
Vo=0.001;
Go=90;
Ao=0;
lat=0;
long=0;
head=90;
head=90-head;
p1=0;
p2=2.269;
p3=1.4;
p4=0;
thrust_data
MAX=max(tt);
incr=max(tt)/(length(tt)-1);
K=(((MAX)/incr)+1);
x0=[Vo Go*(pi()/180) Ao lat*(pi()/180) long*(pi()/180) head*(pi()/180)];
p=[p1*pi()/180 p2 p3 p4];
for N=2:K-1
tspan{N}=0:incr:N*incr;
[t{N},x{N}]=ode45(@mars_ascent_trajectory_burn,tspan{N},x0,[],p);
V{N}=x{N}(1:end,1);
gamma{N}=(180/pi()).*x{N}(1:end,2);
A{N}=x{N}(1:end,3);
LA{N}=(180/pi()).*x{N}(1:end,4);
LO{N}=(180/pi()).*x{N}(1:end,5);
H{N}=-((180/pi()).*x{N}(1:end,6))+90;
for J=N:K
gamma_2{J}={};

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

while abs(gamma_2{J}(K))>0.01
tspan_2{N}=tspan{N}(end):incr:MAX;
Go_2(J)=gamma{N}(end)-0.001*(sind(gamma_2{J}(end))/(abs(sind
(gamma_2{J}(end)))));
x0_2{J}=[V{N}(end) Go_2(J) A{N}(end) LA{N}(end)*(pi()/180) LO{N}
(end)*(pi()/180) (pi()/2)-H{N}(end)*(pi()/180)];
[t_2{J},x_2{J}]=ode45(@mars_rocket_trajectory_burn_2,tspan_2
{J},x0_2{J},[],p);
V_2{J}=x_2{J}(1:end,1);
gamma_2{J}=(180/pi()).*x_2{J}(1:end,2);
A_2{J}=x_2{J}(1:end,3);
LA_2{J}=(180/pi()).*x_2{J}(1:end,4);
LO_2{J}=(180/pi()).*x_2{J}(1:end,5);
H_2{J}=-((180/pi()).*x_2{J}(1:end,6))+90;
end
end
end

I think it has something to do with the fact that I am asking the while loop to test the last value in the gamma_2 entry for K minus one different gamma_2 vectors. Thanks in advance for any help offered.
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