Function definitions are not permitted in this context.

can any one help me , or explain why there is error in the function.

function [V,v,W,w,e] = MLPBP(V,v,W,w,X,T,params)
%function [V,v,W,w,e] = MLPBP(V,v,W,w,X,T,params)
%
% Implementation of the backpropagation learning algorithm for a single
% hidden layer MLP. Returns weights updated by backpropagation over X and T
%
% V is a Q by N matrix of weights for N hidden layer units
% W is an N by O matrix of weights for O output layer units
% v is the bias weight vector (Nx1) for N hidden layer units
% w is the bias weight vector (Ox1) for O output layer units
% X is a Q by M matrix of M training input patterns
% T is a O by M matrix of M training output patterns
% params(1) is the number of training epochs required
% params(2) is the learning rate
% e SSE after each epoch

%Changelog:
% 15 March 2013, haywardr, initial code
% 22 March 2013, haywardr, corrected calculation of deltav and deltaw.
% These incorrectly used deltaV and deltaW rather than the slopes. 
% Added RMSE

%track SSE error in e
e =zeros(1,params(1));

eta = params(2);

[numInputs, numExamples] = size(X);
[numHidden, numOutput] = size(W);

%setup the bias values
hiddenOutputOnes = ones([numHidden numExamples]);
outputOutputOnes = ones([numOutput numExamples]);

numExamplesOnes = ones(1,numExamples);

for i=1:params(1),
    %forward propagate signals
   hiddenOutput = sigmoid((V'*X)-(v*numExamplesOnes));
   outputOutput = sigmoid((W'*hiddenOutput)-(w*numExamplesOnes));

     %calculate the sigmoid derivative at each layer
     hiddenDerivative = hiddenOutput .* (hiddenOutputOnes - hiddenOutput);
     outputDerivative = outputOutput .* (outputOutputOnes - outputOutput);

     %calculate the error at the output layer
     error = (T-outputOutput);

     %gradients for each of the weight matrices
     slopeW = (error .* outputDerivative); %OxM
     slopeV = ((W*slopeW) .* hiddenDerivative); % NxM

     %calculate weight changes
     deltaV = (X * slopeV'); %QxN
     deltav = sum(slopeV,2); %Nx1
     deltaW = (hiddenOutput * slopeW'); %NxO
     deltaw = sum(slopeW,2); %Ox1

     sumSquaredError = sum(sum(error .^2)');
     e(i) = sumSquaredError;
     fprintf('Epoch: %d: SSE=%15.20f RMSE=%15.20f\n',...
         i,sumSquaredError,sqrt(sumSquaredError)/numExamples);

     %adapt weights
     V = V + eta.*deltaV; %QxN
     v = v - eta.*deltav; %Nx1
     W = W + eta.*deltaW; %NxO
     w = w - eta.*deltaw; %Ox1

end

Answer 1

[Image Analyst]

Why is all your code enclosed in braces? Try removing them.

Also review this: http://www.mathworks.com/matlabcentral/answers/13205-tutorial-how-to-format-your-question-with-markup

Answer 2

[Walter Roberson]

You must save the code (without the '{' and '}') to a file named MLPBP.m