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test_err=[];
test_crerr=[];
train_err=[];
train_crerr=[];

fprintf（1‘\nTraining?discriminative?model?on?MNIST?by?minimizing?cross?entropy?error.?\n‘）;
fprintf（1‘60?batches?of?1000?cases?each.?\n‘）;

[numcases?numdims?numbatches]=size（batchdata）;
N=numcases;?

load?fullmnist_dbm
[numdims?numhids]?=?size（vishid）;
[numhids?numpens]?=?size（hidpen）;?

%%%%%%?Preprocess?the?data?%%%%%%%%%%%%%%%%%%%%%%

[testnumcases?testnumdims?testnumbatches]=size（testbatchdata）;
N=testnumcases;
temp_h2_test?=?zeros（testnumcasesnumpenstestnumbatches）;?
for?batch?=?1:testnumbatches
???data?=?[testbatchdata（::batch）];
???[temp_h1?temp_h2]?=?...
???????mf_class（datavishidhidbiasesvisbiaseshidpenpenbiases）;
???temp_h2_test（::batch）?=?temp_h2;
end??

[numcases?numdims?numbatches]=size（batchdata）;
N=numcases;
temp_h2_train?=?zeros（numcasesnumpensnumbatches）;
for?batch?=?1:numbatches
???data?=?[batchdata（::batch）];
???[temp_h1?temp_h2]?=?...
?????mf_class（datavishidhidbiasesvisbiaseshidpenpenbiases）;
???temp_h2_train（::batch）?=?temp_h2;
end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

w1_penhid?=?hidpen‘;
w1_vishid?=?vishid;
w2?=?hidpen;
h1_biases?=?hidbiases;?h2_biases?=?penbiases;?

w_class?=?0.1*randn（numpens10）;?
topbiases?=?0.1*randn（110）;

for?epoch?=?1:maxepoch?

%%%%?TEST?STATS?
%%%%?Error?rates?
???[testnumcases?testnumdims?testnumbatches]=size（testbatchdata）;
???N=testnumcases;
???bias_hid=?repmat（h1_biasesN1）;
???bias_pen?=?repmat（h2_biasesN1）;
???bias_top?=?repmat（topbiasesN1）;

???err=0;
???err_cr=0;
???counter=0;??
???for?batch?=?1:testnumbatches
?????data?=?[testbatchdata（::batch）];
?????temp_h2?=?temp_h2_test（::batch）;?
?????target?=?[testbatchtargets（::batch）];?

?????w1probs?=?1./（1?+?exp（-data*w1_vishid?-temp_h2*w1_penhid?-?bias_hid??））;?
?????w2probs?=?1./（1?+?exp（-w1probs*w2?-?bias_pen））;?
?????targetout?=?exp（w2probs*w_class?+?bias_top?）;
?????targetout?=?targetout./repmat（sum（targetout2）110）;
?????[I?J]=max（targetout[]2）;?
?????[I1?J1]=max（target[]2）;?
?????counter=counter+length（find（J~=J1））;??
?????err_cr?=?err_cr-?sum（sum（?target（:1:end）.*log（targetout）））?;
???end

???test_err（epoch）=counter;
???test_crerr（epoch）=err_cr;
???fprintf（1‘\nepoch?%d?test??misclassification?err?%d?（out?of?10000）??test?cross?entropy?error