I have this for loop, and it seems to not end.

for i=1:n
   Phi1=1;
   Phi2=1;
   gamma1calc(i)=exp(alpha/(1+(alpha/beta)*(x1(i)/x2(i)))^2);
   gamma2calc(i)=exp(beta/(1+(beta/alpha)*(x2(i)/x1(i)))^2);
   Pcalc(i) = ((x1(i)*gamma1calc(i)*P1sat)/(Phi1))+((x2(i)*gamma2calc(i)*P2sat)/(Phi2));
   AE1(i)=1;
        while AE1(i) > 0.0001
            y1calc(i) = (x1(i)*gamma1calc(i)*P1sat)/(Phi1);
            y2calc(i) = 1-y1calc(i);
    
            Phi1calc(i)=exp((B1.*(Pcalc(i)-P1sat)+Pcalc(i).*y2calc(i).^2.*(2.*B12-B1-B2))./(R*T));
            Phi2calc(i)=exp((B2.*(Pcalc(i)-P2sat)+Pcalc(i).*y1calc(i).^2.*(2.*B12-B1-B2))./(R*T));
            Pnew(i) = ((x1(i)*gamma1calc(i)*P1sat)/Phi1calc(i))+((x2(i)*gamma2calc(i)*P2sat)/Phi2calc(i));
            AE2 (i)=abs(Pnew(i)-Pcalc(i));
                if AE2(i) > 0.0001
                     Pcalc(i)=Pnew(i);
                end
        end
    Pcalc(i)=Pnew(i);    
end

[Stephen23]

"I have this for loop, and it seems to not end."

The WHILE loop condition relies on the value of AE1(i). But inside the WHILE loop you do not change any value of AE1.

If you do not change any value of AE1, why do you expect the condition to change?

[Josiah Jarenee Comia]

My bad, I entered the wrong code, I just tested that because im not getting anything. Here's the original. This should work right? I mean the loop structure is correct and all right?

for i=1:n
   Phi1=1;
   Phi2=1;
   gamma1calc(i)=exp(alpha/(1+(alpha/beta)*(x1(i)/x2(i)))^2);
   gamma2calc(i)=exp(beta/(1+(beta/alpha)*(x2(i)/x1(i)))^2);
   Pcalc(i) = ((x1(i)*gamma1calc(i)*P1sat)/(Phi1))+((x2(i)*gamma2calc(i)*P2sat)/(Phi2));
   AE1(i)=1;
        while AE1(i) > 0.0001
            y1calc(i) = (x1(i)*gamma1calc(i)*P1sat)/(Phi1);
            y2calc(i) = 1-y1calc(i);
            Phi1calc(i)=exp((B1.*(Pcalc(i)-P1sat)+Pcalc(i).*y2calc(i).^2.*(2.*B12-B1-B2))./(R*T));
            Phi2calc(i)=exp((B2.*(Pcalc(i)-P2sat)+Pcalc(i).*y1calc(i).^2.*(2.*B12-B1-B2))./(R*T));
            Pnew(i) = ((x1(i)*gamma1calc(i)*P1sat)/Phi1calc(i))+((x2(i)*gamma2calc(i)*P2sat)/Phi2calc(i));
            AE1(i)=abs(Pnew(i)-Pcalc(i));
                if AE1(i) > 0.0001
                     Pcalc(i)=Pnew(i);
                end
        end
    Pcalc(i)=Pnew(i);    
end

[Stephen23]

"This should work right?"

You did not describe the intended algorithm, so I have no way to check if it is implemented correctly or should "work".

"I mean the loop structure is correct and all right?"

That looks like the correct syntax for a WHILE loop.

Answer 1

[Pranav Verma]

Hi Josiah,

I would recommend you to print out the value of AE1(i) inside the loop along with appropriate messages. This will allow you to watch the value of AE1(i) and debug the code easily.

You can use disp function to print out the value and messages.

Thanks