Error Message: Subscript indices must either be real positive integers or logicals. This occurs when running the for loop for the very last value of a. Perhaps someone may be able to assist me.

sigma_lam=.7; sigma_m=.3; sigma_k=1-sigma_m; intgr=ones(1,1101); z=0:1100; zint=(z+1).^(-1); D_1=((sigma_lam*((z+1).^(-3))+sigma_k*((z+1).^(-1))+sigma_m).^(.5))./(z+1).^(-1.5); a=linspace(1/1101,1,1101); aa=num2cell(a); zplusone=0:1100; zplusone=fliplr(zplusone); zplusonea=num2cell(zplusone); scalefactor_z= containers.Map(aa,zplusonea);

for a=linspace(1/1101,1,1101); x=0:.0001:a; y=x.^(1.5)./((sigma_lam*x.^3+sigma_k*x+sigma_m).^(1.5)); intgr(1,scalefactor_z(a))=trapz(x,y); end

    intgr=fliplr(intgr);

    global D_fin
D_fin=intgr.*D_1;

for i=1:1101 f_col(1,i)=erfc(1.69/(sqrt(2)*D_fin(i)*7)); end

plot(z,f_col)

%sigma(M,z)=(D(z)/D(0))*sigma(M,0); %put in D(z)

%then plot f_col

[per isakson]

With the help of the button, {}Code, you could make the code readable.

Answer 1

[per isakson]

The error occurs for the line

    intgr(1,scalefactor_z(a)) = trapz(x,y);

because with a equal to 1

    K>> scalefactor_z(a)
    ans =
         0

which is not a positive integer