i am trying to add the value of a certain function to an array, but there seems to be some error. the code is as follows. could you please help? trying to store the value of Thetahat into A for every x.

function [inseed] = optsim (inseed, nreps)

sum = 0;
sum2 = 0;
for x = 0:5:60
    for j= 1:nreps
        [inseed, profit] = poisprofit(inseed, x);
        sum = sum+profit;
        sum2 =sum2 + profit^2;
    end
    Thetahat = sum/nreps;
    sigmahat  = sqrt(sum2/nreps-Thetahat^2);
    sehatThetahat = sigmahat/sqrt(nreps);

      A(x)= profit;
      D(x) = x;
  end
  end

Answer 1

[Walter Roberson]

Only positive integers can be used as indices.

You should use a pattern more like

sum1 = 0;
sum2 = 0;
xvals = 0:5:60;
for xidx = 1 : length(xvals)
    x = xvals(xidx);
    for j= 1:nreps
        [inseed, profit] = poisprofit(inseed, x);
        sum1 = sum1+profit;
        sum2 =sum2 + profit^2;
    end
    Thetahat = sum1/nreps;
    sigmahat  = sqrt(sum2/nreps-Thetahat^2);
    sehatThetahat = sigmahat/sqrt(nreps);

        A(xidx)= profit;
        D(xidx) = x;
    end
    end