python类argmax()的实例源码

def __build_loss_train__fn__(self):
        # create loss function
        prediction = layers.get_output(self.net)
        loss = objectives.categorical_crossentropy(prediction, self.__target_var__)
        loss = loss.mean() + 1e-4 * regularization.regularize_network_params(self.net, regularization.l2)

        val_acc = T.mean(T.eq(T.argmax(prediction, axis=1), self.__target_var__),dtype=theano.config.floatX)

        # create parameter update expressions
        params = layers.get_all_params(self.net, trainable=True)
        self.eta = theano.shared(sp.array(sp.float32(0.05), dtype=sp.float32))
        update_rule = updates.nesterov_momentum(loss, params, learning_rate=self.eta,
                                                    momentum=0.9)

        # compile training function that updates parameters and returns training loss
        self.__train_fn__ = theano.function([self.__input_var__,self.__target_var__], loss, updates=update_rule)
        self.__predict_fn__ = theano.function([self.__input_var__], layers.get_output(self.net,deterministic=True))
        self.__val_fn__ = theano.function([self.__input_var__,self.__target_var__], [loss,val_acc])

def _parse_plink_snps_(genotype_file, snp_indices):
    plinkf = plinkfile.PlinkFile(genotype_file)
    samples = plinkf.get_samples()
    num_individs = len(samples)
    num_snps = len(snp_indices)
    raw_snps = sp.empty((num_snps,num_individs),dtype='int8')
    #If these indices are not in order then we place them in the right place while parsing SNPs.
    snp_order = sp.argsort(snp_indices)
    ordered_snp_indices = list(snp_indices[snp_order])
    ordered_snp_indices.reverse()
    print 'Iterating over file to load SNPs'
    snp_i = 0
    next_i = ordered_snp_indices.pop()
    line_i = 0
    max_i = ordered_snp_indices[0]
    while line_i <= max_i:
        if line_i < next_i:
            plinkf.next()
        elif line_i==next_i:
            line = plinkf.next()
            snp = sp.array(line, dtype='int8')
            bin_counts = line.allele_counts()
            if bin_counts[-1]>0:
                mode_v = sp.argmax(bin_counts[:2])
                snp[snp==3] = mode_v
            s_i = snp_order[snp_i]
            raw_snps[s_i]=snp
            if line_i < max_i:
                next_i = ordered_snp_indices.pop()
            snp_i+=1
        line_i +=1
    plinkf.close()
    assert snp_i==len(raw_snps), 'Failed to parse SNPs?'
    num_indivs = len(raw_snps[0])
    freqs = sp.sum(raw_snps,1, dtype='float32')/(2*float(num_indivs))
    return raw_snps, freqs

def predict(self,X):
        proba = self.predict_proba(X=X)
        y_pred = sp.argmax(proba,axis=1)
        return sp.array(y_pred)

def cluster(self, X):
        self.fit(X)

        cluster = [X[sp.argmax(self.responsibility, axis=1) == k] for k in range(self.n_classes)]
        mean = self.center
        cov = [sp.cov(c, rowvar=0, ddof=0) for c in cluster]

        return cluster, mean, cov