dgl.function.sum¶

dgl.function.sum(msg, out)[source]¶

Builtin reduce function that aggregates messages by sum.

Parameters:	msg (str) – The message field. out (str) – The output node feature field.

Examples

>>> import dgl
>>> reduce_func = dgl.function.sum(msg='m', out='h')

The above example is equivalent to the following user defined function (if using PyTorch):

>>> import torch
>>> def reduce_func(nodes):
>>>     return {'h': torch.sum(nodes.mailbox['m'], dim=1)}