crf.py 文件源码

def __init__(self, incoming, num_labels, mask_input=None, W=init.GlorotUniform(), b=init.Constant(0.), **kwargs):
        # This layer inherits from a MergeLayer, because it can have two
        # inputs - the layer input, and the mask.
        # We will just provide the layer input as incomings, unless a mask input was provided.

        self.input_shape = incoming.output_shape
        incomings = [incoming]
        self.mask_incoming_index = -1
        if mask_input is not None:
            incomings.append(mask_input)
            self.mask_incoming_index = 1

        super(ChainCRFLayer, self).__init__(incomings, **kwargs)
        self.num_labels = num_labels + 1
        self.pad_label_index = num_labels

        num_inputs = self.input_shape[2]
        self.W = self.add_param(W, (num_inputs, self.num_labels, self.num_labels), name="W")

        if b is None:
            self.b = None
        else:
            self.b = self.add_param(b, (self.num_labels, self.num_labels), name="b", regularizable=False)