import numpy
import theano
from theano import tensor
from blocks.bricks import MLP, Rectifier, Linear, Sigmoid, Identity, Softmax
from blocks.bricks.lookup import LookupTable
from blocks.initialization import IsotropicGaussian, Constant
import data
import error
class Model(object):
def __init__(self, config):
# The input and the targets
x_firstk_latitude = (tensor.matrix('first_k_latitude') - data.porto_center[0]) / data.data_std[0]
x_firstk_longitude = (tensor.matrix('first_k_longitude') - data.porto_center[1]) / data.data_std[1]
x_lastk_latitude = (tensor.matrix('last_k_latitude') - data.porto_center[0]) / data.data_std[0]
x_lastk_longitude = (tensor.matrix('last_k_longitude') - data.porto_center[1]) / data.data_std[1]
input_list = [x_firstk_latitude, x_firstk_longitude, x_lastk_latitude, x_lastk_longitude]
embed_tables = []
self.require_inputs = ['first_k_latitude', 'first_k_longitude', 'last_k_latitude', 'last_k_longitude']
for (varname, num, dim) in config.dim_embeddings:
self.require_inputs.append(varname)
vardata = tensor.lvector(varname)
tbl = LookupTable(length=num, dim=dim, name='%s_lookup'%varname)
embed_tables.append(tbl)
input_list.append(tbl.apply(vardata))
y = tensor.concatenate((tensor.vector('destination_latitude')[:, None],
tensor.vector('destination_longitude')[:, None]), axis=1)
# Define the model
mlp = MLP(activations=[Rectifier() for _ in config.dim_hidden] + [Softmax()],
dims=[config.dim_input] + config.dim_hidden + [config.dim_output])
classes = theano.shared(numpy.array(config.tgtcls, dtype=theano.config.floatX), name='classes')
# Create the Theano variables
inputs = tensor.concatenate(input_list, axis=1)
# inputs = theano.printing.Print("inputs")(inputs)
cls_probas = mlp.apply(inputs)
outputs = tensor.dot(cls_probas, classes)
# outputs = theano.printing.Print("outputs")(outputs)
# y = theano.printing.Print("y")(y)
outputs.name = 'outputs'
# Calculate the cost
cost = error.erdist(outputs, y).mean()
cost.name = 'cost'
hcost = error.hdist(outputs, y).mean()
hcost.name = 'hcost'
# Initialization
for tbl in embed_tables:
tbl.weights_init = IsotropicGaussian(0.01)
mlp.weights_init = IsotropicGaussian(0.1)
mlp.biases_init = Constant(0.01)
for tbl in embed_tables:
tbl.initialize()
mlp.initialize()
self.cost = cost
self.monitor = [cost, hcost]
self.outputs = outputs
self.pred_vars = ['destination_latitude', 'destination_longitude']
