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ga optimization of nn weights
Posted:
Feb 6, 2013 11:52 AM


% Subject: ga optimization of nn weights % From: Syed Umar Amin <syed.umar.amin@gmail.com> % Sent: Feb 4, 2013 11:17:22 AM
getting error Index exceeds matrix dimensions. pls help
Name Size Bytes Class Attributes cancerInputs 9x699 50328 double cancerTargets 2x699 11184 double
function mse_calc = mse_test(x, net, inputs, targets) % 'x' contains the weights and biases vector % in row vector form as passed to it by the % genetic algorithm. This must be transposed % when being set as the weights and biases % vector for the network. % To set the weights and biases vector to the % one given as input net = setwb(net, x); % To evaluate the ouputs based on the given % weights and biases vector y = net(inputs); % Calculating the mean squared error mse_calc = sum((ytargets).^2)/length(y); end % inputs for the neural net inputs = cancerInputs; % targets for the neural net targets = cancerTargets; % number of neurons n = 10; % create a neural network net = feedforwardnet(n); % configure the neural network for this dataset net = configure(net, inputs, targets); % create handle to the MSE_TEST function, that % calculates MSE h = @(x) mse_test(x, net, inputs, targets); % Setting the Genetic Algorithms tolerance for % minimum change in fitness function before % terminating algorithm to 1e8 and displaying % each iteration's results. ga_opts = gaoptimset('TolFun', 1e8,'display','iter'); % PLEASE NOTE: For a feedforward network % with n neurons, 3n+1 quantities are required % in the weights and biases column vector. % % a. n for the input weights % b. n for the input biases % c. n for the output weights % d. 1 for the output bias % running the genetic algorithm with desired options [x_ga_opt, err_ga] = ga(h, 3*n+1, ga_opts); Error: Index exceeds matrix dimensions.



