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@@ -1,82 +0,0 @@
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-function svmmodel = liblinear_train_multicore ( labels, feat, settings )
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-%
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-% BRIEF
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-% A simple wrapper to provide training of 1-vs-all-classification for LIBLINEAR. No
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-% further settings are adjustable currently.
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-%
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-% INPUT
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-% labels -- multi-class labels (#sample x 1)
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-% feat -- features for training images (#samples x # dimensions)
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-% settings -- struct for configuring the svm model training, e.g., via
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-% 'b_verbose', 'f_svm_C', ...
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-%
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-% OUTPUT:
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-% svmmodel -- cell ( #classes x 1 ), every model entry is obtained via
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-% svmtrain of the corresponding 1-vs-all-problem
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-%
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-% date: 30-04-2014 ( dd-mm-yyyy )
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-% author: Alexander Freytag
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-
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- if ( nargin < 3 )
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- settings = [];
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- end
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-
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-
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- libsvm_options = '';
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-
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- % outputs for training
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- if ( ~ getFieldWithDefault ( settings, 'b_verbose', false ) )
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- libsvm_options = sprintf('%s -q', libsvm_options);
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- end
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-
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- % cost parameter
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- f_svm_C = getFieldWithDefault ( settings, 'f_svm_C', 1);
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- libsvm_options = sprintf('%s -c %f', libsvm_options, f_svm_C);
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-
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- % do we want to use an offset for the hyperplane?
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- if ( getFieldWithDefault ( settings, 'b_addOffset', false) )
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- libsvm_options = sprintf('%s -B 1', libsvm_options);
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- end
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-
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- % which solver to use
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- % copied from the liblinear manual:
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-% for multi-class classification
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-% 0 -- L2-regularized logistic regression (primal)
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-% 2 -- L2-regularized L2-loss support vector classification (primal)
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-% 11 -- l2-loss SVR
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- i_svmSolver = getFieldWithDefault ( settings, 'i_svmSolver', 2);
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- i_numThreads = getFieldWithDefault ( settings, 'i_numThreads', 2);
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- libsvm_options = sprintf('%s -s %d -n %d', libsvm_options, i_svmSolver, i_numThreads);
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-
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-
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- % increase penalty for positive samples according to invers ratio of
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- % their number, i.e., if 1/3 is ratio of positive to negative samples, then
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- % impact of positives is 3 the times of negatives
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- %
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- b_weightBalancing = getFieldWithDefault ( settings, 'b_weightBalancing', false);
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-
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-
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-
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- uniqueLabels = unique ( labels );
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- i_numClasses = size ( uniqueLabels,1);
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-
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-
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- %# train one-against-all models
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-
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- if ( ~b_weightBalancing)
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- svmmodel = train( labels, feat, libsvm_options );
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- else
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- svmmodel = cell( i_numClasses,1);
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- for k=1:i_numClasses
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- yBin = 2*double( labels == uniqueLabels( k ) )-1;
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-
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- fraction = double(sum(yBin==1))/double(numel(yBin));
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- libsvm_optionsLocal = sprintf('%s -w1 %f', libsvm_options, 1.0/fraction);
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- svmmodel{ k } = train( yBin, feat, libsvm_optionsLocal );
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-
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- %store the unique class label for later evaluations.
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- svmmodel{ k }.uniqueLabel = uniqueLabels( k );
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- end
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- end
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-
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-end
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