function [ X,header ] = pnFeatures(data,featType)
%PNFEATURES Extract features for a given model
% [ X,header ] = pnFeatures(data,featType) extracts features for the data
% given the type of features requested. These features are in double
% matrix form and can be used in model development algorithms.
%
% Inputs:
% data - Cell array of data.
% Column 1 - Subject IDs
% Column 2 - Time stamp vectors for each subject
% Column 3 - Feature name vectors for each subject
% Column 4 - Data value vectors for each subject
%
% featType - The type of features to extract
%
% Outputs:
% X - Double matrix NxD with D features needed for training.
% header - Cell array 1xD of labels for each feature used.
%
%
% Example
% bpath = './set-a/';
% data = pnLoadTextFilesCell(bpath);
% stat = pnFeatures(data(1,:)) %
% See also PNGENERATEFEATURES
% References:
% Physionet Challenge 2012
% Copyright 2012 Alistair Johnson
% $LastChangedBy: alistair $
% $LastChangedDate: 2012-08-23 18:39:12 -0400 (Thu, 23 Aug 2012) $
% $Revision: 152 $
% Originally written on GLNXA64 by Alistair Johnson, 21-Jun-2012 13:00:48
% Contact: alistairewj@gmail.com
if nargin<2
featType = 'Base';
end
%=== Get the type of features to be extracted/default to base as needed
switch featType
case {'Complexity'}
featfcn = @pnComplexityFeatures;
case {'Plus'}
featfcn = @pnPlusFeatures;
case {'Base'}
featfcn = @pnBaseFeatures;
case {'Andrew'}
featfcn = @pnAndrewFeatures;
case {'LouisOld'}
featfcn = @pnLouisOldFeatures;
case {'Louis'}
featfcn = @pnLouisFeatures;
case {'GSO21','ReliefF1','CFS1','CBF1','jmi1','mrmr1','disr1','all1'}
k = 1;
featfcn = @(x) pnThanasisFeatures(x,featType,k);
case {'GSO22','ReliefF2','CFS2','CBF2','jmi2','mrmr2','disr2','all2'}
k = 2;
featfcn = @(x) pnThanasisFeatures(x,featType,k);
case {'GSO23','ReliefF3','CFS3','CBF3','jmi3','mrmr3','disr3','all3'}
k = 3;
featfcn = @(x) pnThanasisFeatures(x,featType,k);
%=== default is using fold 4 of thanasis' feature selection
case {'GSO2','ReliefF','CFS','CBF','jmi','mrmr','disr','all',...
'GSO24','ReliefF4','CFS4','CBF4','jmi4','mrmr4','disr4','all4'}
k = 4;
featfcn = @(x) pnThanasisFeatures(x,featType,k);
otherwise
fprintf('Feature function not found! Using BASE features.');
featfcn = @pnBaseFeatures;
end
[X,header] = featfcn(data);
end