Python layers.Dropout方法代碼示例

# 需要導入模塊: from neon import layers [as 別名]
# 或者: from neon.layers import Dropout [as 別名]
def gen_model(num_channels, height, width):
    assert NervanaObject.be is not None, 'need to generate a backend before using this function'

    init_uni = Kaiming()

    # we have 1 issue, they have bias layers we don't allow batchnorm and biases
    conv_common = dict(padding=1, init=init_uni, activation=Rectlin(), batch_norm=True)

    # set up the layers
    layers = []

    # need to store a ref to the pooling layers to pass
    # to the upsampling layers to get the argmax indicies
    # for upsampling, this stack holds the pooling layer refs
    pool_layers = []

    # first loop generates the encoder layers
    nchan = [64, 128, 256, 512, 512]
    for ind in range(len(nchan)):
        nchanu = nchan[ind]
        lrng = 2 if ind <= 1 else 3
        for lind in range(lrng):
            nm = 'conv%d_%d' % (ind+1, lind+1)
            layers.append(Conv((3, 3, nchanu), strides=1, name=nm, **conv_common))

        layers.append(Pooling(2, strides=2, name='conv%d_pool' % ind))
        pool_layers.append(layers[-1])
        if ind >= 2:
            layers.append(Dropout(keep=0.5, name='drop%d' % (ind+1)))

    # this loop generates the decoder layers
    for ind in range(len(nchan)-1,-1,-1):
        nchanu = nchan[ind]
        lrng = 2 if ind <= 1 else 3
        # upsampling layers need a ref to the corresponding pooling layer
        # to access the argmx indices for upsampling
        layers.append(Upsampling(2, pool_layers.pop(), strides=2, padding=0,
                      name='conv%d_unpool' % ind))
        for lind in range(lrng):
            nm = 'deconv%d_%d' % (ind+1, lind+1)
            if ind < 4 and lind == lrng-1:
                nchanu = nchan[ind]/2
            layers.append(Conv((3, 3, nchanu), strides=1, name=nm, **conv_common))
            if ind == 0:
                break
        if ind >= 2:
            layers.append(Dropout(keep=0.5, name='drop%d' % (ind+1)))

    # last conv layer outputs 12 channels, 1 for each output class
    # with a pixelwise softmax over the channels
    act_last = PixelwiseSoftmax(num_channels, height, width, name="PixelwiseSoftmax")
    conv_last = dict(padding=1, init=init_uni, activation=act_last, batch_norm=False)
    layers.append(Conv((3, 3, num_channels), strides=1, name='deconv_out', **conv_last))
    return layers 

# 需要導入模塊: from neon import layers [as 別名]
# 或者: from neon.layers import Dropout [as 別名]
def main():
    parser = get_parser()
    args = parser.parse_args()
    print('Args:', args)

    loggingLevel = logging.DEBUG if args.verbose else logging.INFO
    logging.basicConfig(level=loggingLevel, format='')

    ext = extension_from_parameters(args)

    loader = p1b3.DataLoader(feature_subsample=args.feature_subsample,
                             scaling=args.scaling,
                             drug_features=args.drug_features,
                             scramble=args.scramble,
                             min_logconc=args.min_logconc,
                             max_logconc=args.max_logconc,
                             subsample=args.subsample,
                             category_cutoffs=args.category_cutoffs)

    # initializer = Gaussian(loc=0.0, scale=0.01)
    initializer = GlorotUniform()
    activation = get_function(args.activation)()

    layers = []
    reshape = None

    if args.convolution and args.convolution[0]:
        reshape = (1, loader.input_dim, 1)
        layer_list = list(range(0, len(args.convolution), 3))
        for l, i in enumerate(layer_list):
            nb_filter = args.convolution[i]
            filter_len = args.convolution[i+1]
            stride = args.convolution[i+2]
            # print(nb_filter, filter_len, stride)
            # fshape: (height, width, num_filters).
            layers.append(Conv((1, filter_len, nb_filter), strides={'str_h':1, 'str_w':stride}, init=initializer, activation=activation))
            if args.pool:
                layers.append(Pooling((1, args.pool)))

    for layer in args.dense:
        if layer:
            layers.append(Affine(nout=layer, init=initializer, activation=activation))
        if args.drop:
            layers.append(Dropout(keep=(1-args.drop)))
    layers.append(Affine(nout=1, init=initializer, activation=neon.transforms.Identity()))

    model = Model(layers=layers)

    train_iter = ConcatDataIter(loader, ndata=args.train_samples, lshape=reshape, datatype=args.datatype)
    val_iter = ConcatDataIter(loader, partition='val', ndata=args.val_samples, lshape=reshape, datatype=args.datatype)

    cost = GeneralizedCost(get_function(args.loss)())
    optimizer = get_function(args.optimizer)()
    callbacks = Callbacks(model, eval_set=val_iter, **args.callback_args)

    model.fit(train_iter, optimizer=optimizer, num_epochs=args.epochs, cost=cost, callbacks=callbacks)