Vectors must be the same length (leslie matrix)

I was asked to do this: Change the adult bison fecundity to 0.2, 0.42, 1.0, and 1.4. Create one graph that has adult fecundity along the horizontal axis and equilibrium population structure along the vertical axis with a data set plotted for each population class (calves, yearlings, and adults).

Here's the code:

 % Filename: LeslieFecundity.m
% M-file to
%      - Find the dominant eigenvalue and corresponding
%        eigenvector for an array of juvenile fecundities
%      - Print out a table of the results
%      - Print out results graphically

 % Print out the header for the table
fprintf('Adult      Dominant       Equilibrium Structure    \n')
fprintf('Fecundity  Eigenvalue  Calves  Yearlings  Adults\n')
fprintf('------------------------------------------------------\n')

 % Array of adult fecudity values
f = [0.2, 0.42, 1 1.4];

 % Start the loop
for i = 1:length(f) % loop thru length of f vector

    % Construct Leslie matrix with appropriate adult fecundity
    A = [   0   0    f(i) ;
          0.6   0    0 ;
            0  0.75  0.95 ];

    % Get eigenvalues and eigenvectors
    [v,lambda] = eig(A);

 % Find dominant eigenvalue in lambda
% and make note of position in lambda matrix
lambdavector = max(lambda); % array of eigenvalues
for j = 1:length(lambdavector)
if max(max(abs(lambda))) == abs(lambdavector(j))
loc = j; % position of dom eig in lambda matrix
deig = lambda(j,j); % dominant eigenvalue
end
end

 % Normalize eigenvector associated with dominant eigenvalue
normv(:,i) = v(:,loc)/sum(v(:,loc));
% This creates a matrix called normv in which the

 % iˆth column corresponds to the dominant eigenvector

    % Print these values
    fprintf('   %3.1f   ',f(i)) % adult fecundity value
    fprintf('     %5.3f   ',deig) % dominant eigenvalue
    fprintf('   %5.3f  ',normv(1,i)) % calf proprotion at eq
    fprintf('     %5.3f  ',normv(2,i)) % yearling proprotion at eq
    fprintf('   %5.3f  ',normv(3,i)) % adult proprotion at eq
    fprintf('\n') % new line    
end

 % Generate graph
c = normv(1,:);  % vector of calf proportions at eq
y = normv(2,:);  % vector of yearling proportions at eq
a = normv(3,:);  % vector of adult proprotions at eq
plot(f,c,'r.-',f,y,'g.-',f,a,'b.-')
legend('calves','yearlings','adults')
xlabel('Adult Fecundity')
ylabel('Equilibrium Structure')

[madhan ravi]

what problem are you facing , I didn't get any errors when running your code?

[Rhi Bronson]

It keeps giving me the "vector must be the same length" error when i try to plot the table.

Answer 1

[madhan ravi]

fprintf('Adult      Dominant       Equilibrium Structure    \n')
fprintf('Fecundity  Eigenvalue  Calves  Yearlings  Adults\n')
fprintf('------------------------------------------------------\n')
 f = [0.2, 0.42, 1 1.4];

% Start the loop 
for i = 1:length(f) % loop thru length of f vector

      % Construct Leslie matrix with appropriate adult fecundity
      A = [   0   0    f(i) ;
            0.6   0    0 ;
              0  0.75  0.95 ];
      % Get eigenvalues and eigenvectors
      [v,lambda] = eig(A);
  % Find dominant eigenvalue in lambda % and make note of position in lambda matrix l
  lambdavector = max(lambda); % array of eigenvalues 
  for j = 1:length(lambdavector) 
      if max(max(abs(lambda))) == abs(lambdavector(j)) 
          loc = j; % position of dom eig in lambda matrix 
          deig = lambda(j,j); % dominant eigenvalue
      end
  end

% Normalize eigenvector associated with dominant eigenvalue 
normv(:,i) = v(:,loc)/sum(v(:,loc)); % This creates a matrix called normv in which the

% iˆth column corresponds to the dominant eigenvector

      % Print these values
      fprintf('   %3.1f   ',f(i)) % adult fecundity value
      fprintf('     %5.3f   ',deig) % dominant eigenvalue
      fprintf('   %5.3f  ',normv(1,i)) % calf proprotion at eq
      fprintf('     %5.3f  ',normv(2,i)) % yearling proprotion at eq
      fprintf('   %5.3f  ',normv(3,i)) % adult proprotion at eq
      fprintf('\n') % new line    
  end
  % Generate graph 
  c = normv(1,:); % vector of calf proportions at eq 
  y = normv(2,:); % vector of yearling proportions at eq 
  a = normv(3,:); % vector of adult proprotions at eq 
  plot(f,c,'r.-',f,y,'g.-',f,a,'b.-')
  legend('calves','yearlings','adults') 
  xlabel('Adult Fecundity')
  ylabel('Equilibrium Structure')

[madhan ravi]

see the graph in the attached screenshot , I got them without any flaws

[Rhi Bronson]

I copied and pasted your code, and it's still giving me the error. The table is created, but it's not graphing the data for me

[madhan ravi]

try clear all at the beginning and then try because I have no idea why its not working for you. also paste the code here what you are trying?

[madhan ravi]

>> COMMUNITY
Adult      Dominant       Equilibrium Structure    
Fecundity  Eigenvalue  Calves  Yearlings  Adults
------------------------------------------------------
   0.2        1.034      0.148       0.086     0.766  
   0.4        1.105      0.240       0.130     0.630  
   1.0        1.242      0.367       0.177     0.456  
   1.4        1.315      0.417       0.191     0.392  
>> size(f)

ans =

       1     4

>> size(y)

ans =

       1     4

>> size(c)

ans =

       1     4

>> size(a)

ans =

       1     4

>>

[Rhi Bronson]

"clear all" worked! thank you so much

[madhan ravi]

Anytime :) accept the answer if it worked