def _reset()

in gym/gym/envs/parameter_tuning/convergence.py [0:0]


    def _reset(self):

        reg = WeightRegularizer()

        # a hack to make regularization variable
        reg.l1 = K.variable(0.0)
        reg.l2 = K.variable(0.0)


        data, nb_classes = self.data_mix()
        X, Y, Xv, Yv = data

        # input square image dimensions
        img_rows, img_cols = X.shape[-1], X.shape[-1]
        img_channels = X.shape[1]
        # save number of classes and instances
        self.nb_classes = nb_classes
        self.nb_inst = len(X)

        # convert class vectors to binary class matrices
        Y = np_utils.to_categorical(Y, nb_classes)
        Yv = np_utils.to_categorical(Yv, nb_classes)

        # here definition of the model happens
        model = Sequential()

        # double true for icnreased probability of conv layers
        if random.choice([True, True, False]):

            # Choose convolution #1
            self.convAsz = random.choice([32,64,128])

            model.add(Convolution2D(self.convAsz, 3, 3, border_mode='same',
                                    input_shape=(img_channels, img_rows, img_cols),
                                    W_regularizer = reg,
                                    b_regularizer = reg))
            model.add(Activation('relu'))

            model.add(Convolution2D(self.convAsz, 3, 3,
                                    W_regularizer = reg,
                                    b_regularizer = reg))
            model.add(Activation('relu'))

            model.add(MaxPooling2D(pool_size=(2, 2)))
            model.add(Dropout(0.25))

            # Choose convolution size B (if needed)
            self.convBsz = random.choice([0,32,64])

            if self.convBsz > 0:
                model.add(Convolution2D(self.convBsz, 3, 3, border_mode='same',
                                        W_regularizer = reg,
                                        b_regularizer = reg))
                model.add(Activation('relu'))

                model.add(Convolution2D(self.convBsz, 3, 3,
                                        W_regularizer = reg,
                                        b_regularizer = reg))
                model.add(Activation('relu'))

                model.add(MaxPooling2D(pool_size=(2, 2)))
                model.add(Dropout(0.25))

            model.add(Flatten())

        else:
            model.add(Flatten(input_shape=(img_channels, img_rows, img_cols)))
            self.convAsz = 0
            self.convBsz = 0

        # choose fully connected layer size
        self.densesz = random.choice([256,512,762])

        model.add(Dense(self.densesz,
                                W_regularizer = reg,
                                b_regularizer = reg))
        model.add(Activation('relu'))
        model.add(Dropout(0.5))

        model.add(Dense(nb_classes,
                                W_regularizer = reg,
                                b_regularizer = reg))
        model.add(Activation('softmax'))

        # let's train the model using SGD + momentum (how original).
        sgd = SGD(lr=0.01, decay=1e-6, momentum=0.9, nesterov=True)
        model.compile(loss='categorical_crossentropy',
                      optimizer=sgd,
                      metrics=['accuracy'])

        X = X.astype('float32')
        Xv = Xv.astype('float32')
        X /= 255
        Xv /= 255

        self.data = (X,Y,Xv,Yv)
        self.model = model
        self.sgd = sgd

        # initial accuracy values
        self.best_val = 0.0
        self.previous_acc = 0.0

        self.reg = reg
        self.epoch_idx = 0

        return self._get_obs()