likelihoods.py 文件源码

def _partition_and_stitch(self, args, func_name):
        """
        args is a list of tensors, to be passed to self.likelihoods.<func_name>

        args[-1] is the 'Y' argument, which contains the indexes to self.likelihoods.

        This function splits up the args using dynamic_partition, calls the
        relevant function on the likelihoods, and re-combines the result.
        """
        # get the index from Y
        Y = args[-1]
        ind = tf.gather(tf.transpose(Y), tf.shape(Y)[1]-1)  # ind = Y[:,-1]
        ind = tf.cast(ind, tf.int32)
        Y = tf.transpose(tf.gather(tf.transpose(Y), tf.range(0, tf.shape(Y)[1]-1)))  # Y = Y[:,:-1]
        args[-1] = Y

        # split up the arguments into chunks corresponding to the relevant likelihoods
        args = zip(*[tf.dynamic_partition(X, ind, self.num_likelihoods) for X in args])

        # apply the likelihood-function to each section of the data

        with params_as_tensors_for(self, convert=False):
            funcs = [getattr(lik, func_name) for lik in self.likelihood_list]
        results = [f(*args_i) for f, args_i in zip(funcs, args)]

        # stitch the results back together
        partitions = tf.dynamic_partition(tf.range(0, tf.size(ind)), ind, self.num_likelihoods)
        results = tf.dynamic_stitch(partitions, results)

        return results