Index in position 1 exceeds array bounds (must not exceed 2).

ns     = 1;
Ac     = 1.68;
Cp     = 4184;
emode  = 1;
m_test = 0.023;
a0     = 0.745;
a1     = 2.3478;
a2     = 0.0005;
m_c     = 0.03864;
Ti = 328;
To(1,1) = 328;
To(2,1) = 328;
Q_aux = 0;
t=1;
time(t,1)=60;
k_mL = 1;
it = 1380;
dt = 60; 

fileID = fopen('x.txt','r');
indata = textscan(fileID, '%f %f %f', 'HeaderLines',1);
fclose(fileID);

storedvalue{1} = indata{1};
storedvalue{2} = indata{2};
storedvalue{3} = indata{3};
X_data  = storedvalue{1};
Y1_data = storedvalue{2};
Y2_data = storedvalue{3};

if t == 1
    Num_useful  = 0;
    Deno        = 0;
end

for t=1:1:it
    
    t = t+1; 
    time(t,1)= time(t-1,1) + dt/60;
    
    minute = [60 120 180 240 300 360 420 480 540 600 660 720 780 840 900 960 1020 1080 1140 1200 1260 1320 1380 1440];
    
    Ti1 = [327.71 327.42 327.11 326.75 326.29 325.54 323.92 321.44 319.11 317.11 315.34 314.14 313.16 312.05 311.3 310.15 308.8 307.76 304.07 299.47 297.1 295.47 295.02 294.5];
    Ti (t,1) = interp1(minute,Ti1,time(t,1));
    
    Ta1 = [290.2 290.2 290.2 290.8 290.2 289.7 290.8 290.2 290.8 291.3 291.3 291.9 291.9 291.9 291.9 291.9 291.3 290.8 290.8 290.2 290.8 290.2 290.2 290.2];
    Ta(t,1) = interp1(minute,Ta1,time(t,1));
    
    gt1      = [0 0 0 0 0 4.92 196.18 398.82 570.13 697.19 771.13 786.88 743.34 643.52 494.30 306.29 96.37 0 0 0 0 0 0 0];
    gt(t,1) = interp1(minute,gt1,time(t,1));

    xkatd = 0.0431;
    storedvalue{4} = xkatd;
    conv = 0.001;
    xkat=0.85;
        
    To1 = To(t-1,1);
    
    for i = 1:500
            frulp  = a1 + a2*(Ti(t,1) - Ta(t,1));
            fratio = 1;
        
        FRTan = fratio*a0;
        FRUl  = fratio*a1;
        FRtwo = fratio*a2; 
        FRUlp = fratio*frulp;
        
        ratio = 1;
            
            if Ti(t,1)  < 323
                Q_aux(t,1)=1500;
                Ti(t,1)=Ti(t,1)+ Q_aux(t,1)/(m_c*Cp);
                qu(t,1)  = ratio*Ac*( FRTan*xkat*gt(t,1) - FRUlp*(Ti(t,1) - Ta(t,1)));
                sf(t,1)=(qu(t,1)/(qu(t,1)+Q_aux(t,1)))*100;
                To(t,1)  = qu(t,1)/m_c/Cp + Ti(t,1);
            elseif Ti(t,1) >= 333
                Q_aux(t,1)=0;
                Ti(t,1)=Ti(t,1);
                qu(t,1)  = ratio*Ac*( FRTan*xkat*gt(t,1) - FRUlp*(Ti(t,1) - Ta(t,1)));
                sf(t,1)=(qu(t,1)/(qu(t,1)+Q_aux(t,1)))*100;
                To(t,1)  = qu(t,1)/m_c/Cp + Ti(t,1);
            end
            
            if  (Ac <= 0) || (gt(t,1) <= 0) || (qu(t,1)<=0)
                Effic(t,1) = 0;
                qu(t,1)=0;
                sf(t,1)=0;
            else
                Effic(t,1) = qu(t,1)/gt(t,1)/Ac;
            end
        end
        
        
        if  (abs(To(t,1) - To1) > conv)
            To1 = To(t,1);
        else
            break;
        end
        
        if ( To(t,1) - Ti(t,1)) > 8
            m_c = 0.03864;
        elseif (To(t,1) - Ti(t,1)) < 0
            m_c = 0;
        end
    end
end

I am getting the following error

Index in position 1 exceeds array bounds (must not exceed 2).

Error in Code (line 184)
        if  (abs(To(t,1) - To1) > conv)

Can someone please help me?

[KSSV]

You will get this error when you try to extract more number of elements than present in the array. Check your To, it is of size 2*1 and you might be trying to extract To(3). Check your intialization.

[Jay]

what can I do?

[Rena Berman]

(Answers Dev) Restored edit

Answer 1

[Matt J]

How can To(t,1) make sense when t becomes greater than 2? To is only a length 2 vector.

[Jay]

what can I do?

[Image Analyst]

Put in comments so we can understand what you did. Often when you do that you'll discover the error on your own. But at least then, if you still haven't found it, we'll have a chance at understanding what you did and what you want.

[Matt J]

what can I do?

You should make sure To and other vector are the correct length.