MATLAB: Receiving non-integer number results on a matrix model code

matrix modelsSymbolic Math Toolbox

Hello, everyone.
First, I would like to state that I am something of a coding idiot. If we were in person, I would ask you to speak slowly and loudly, but this is the internet, so I instead ask your patience if my question is seemingly obvious.
I'm also probably posting what is an annoying amount of code, but I have no clue where the problem lies, so I want to provide as much information as possible.
Here is the code I am trying to run. I have put '###' around the two troublesome lines:
   meanvr = [.56552  0.195165  2.835  .5500];
  vrhi = [.861332  0.250000  3.000  .41844];
  vrlo = [.405612  0.175165  2.755  .37063];
  syms AS JS Fe Pf
  Svr = [AS JS Fe Pf];
  mx = [0,   JS*Fe*Pf;
        JS,  AS];
  reps=500;
rand('state',sum(100*clock));
numvrs = length(meanvr);
allvrs = rand(reps,numvrs); 
allvrs = allvrs.*repmat(vrhi-vrlo,reps,1) + repmat(vrlo,reps,1);
for rr = 1:reps
    disp(rr);
    realmx=subs(mx,Svr,allvrs(rr,:));
    [lambdas,lambda1,W,w,V,v]=eigenall(realmx);
    sensmx=v*w'/(v'*w);
    elastmx=(sensmx.*realmx)/lambda1;
    alllams(rr,1)=lambda1;
    for xx=1:numvrs
        diffofvr=subs(diff(mx,Svr(xx)),Svr,allvrs(rr,:));
        vrsens(xx)=sum(sum(sensmx.*diffofvr));
    end;
    allelasts(rr,:)=((vrsens.*allvrs(rr,:))/lambda1);
end;
realmx=subs(mx,Svr,meanvr);
[lambdas,lambda1,W,w,V,v]=eigenall(realmx);
meanlam1=lambda1; sensmx=v*w'/(v'*w);
elastmx=(sensmx.*realmx)/lambda1;
meansens = zeros(1,numvrs);
for xx = 1: numvrs
    diffofvr=subs(diff(mx,Svr(xx)),Svr,meanvr);
    meansens(xx) = sum(sum(sensmx.*diffofvr));
end;
meanelast=((meansens.*meanvr)/lambda1);
maxlams=zeros(1,numvrs);
for rate = 1:numvrs
    vrates=meanvr; vrates(rate)=vrhi(rate);
    realmx=subs(mx,Svr,vrates);
    [lambdas,lambda1,W,w,V,v]=eigenall(realmx);
    maxlams(rate)=lambda1;
end;
disp('Below are the maximum lambdas and max proportional')
disp('change in lambdas from changing each vital rate')
disp(Svr); disp(maxlams)
###disp((maxlams-ones(1,numvrs)*meanlam1)/meanlam1)###
disp('Below are the x^2 values for lambda and each')
disp('vital rate, a measure of influence on population')
disp('growth for the random simulated matrices')
correls=corrcoef(double([allvrs, alllams]));
disp(Svr); disp((correls(numvrs+1,1:numvrs)).^2);
disp('Below are the elasticities for the mean vital rates,')
disp('and then the min, max, mean, and st. deviation of the')
disp('elasticity values from the random matrices')
###disp(Svr); disp(meanelast);###
disp(min(double(allelasts))); disp(max(double(allelasts)));
disp(mean(double(allelasts))); disp(std(double(allelasts)));
However, when I run the code, I get very odd numbers as results for those two troublesome lines. For example, the first row of numbers is what I would expect, but the second is… well:
Below are the maximum lambdas and max proportional
change in lambdas from changing each vital rate
[ AS, JS, Fe, Pf]
      0.9255    0.7040    0.6606    0.6365
[ -(113049347475759065049474359227755610434514^(1/2)/900719925474099200000 - 9045809355840329847/14073748835532800000)/(113049347475759065049474359227755610434514^(1/2)/900719925474099200000 + 7069/25000), -(113049347475759065049474359227755610434514^(1/2)/900719925474099200000 - 92622050966827273/219902325555200000)/(113049347475759065049474359227755610434514^(1/2)/900719925474099200000 + 7069/25000), -(113049347475759065049474359227755610434514^(1/2)/900719925474099200000 - 5318325929310998597/14073748835532800000)/(113049347475759065049474359227755610434514^(1/2)/900719925474099200000 + 7069/25000), -(113049347475759065049474359227755610434514^(1/2)/900719925474099200000 - 4978563237831842347/14073748835532800000)/(113049347475759065049474359227755610434514^(1/2)/900719925474099200000 + 7069/25000)]
Any help anyone is willing to give is much appreciated.

Best Answer

disp(double(meanelast))
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