请问负采样策略如何按照频次采样，而不是随机采样

如题。代码中实现了sample_node和sample_node_with_src，请问对于实现按照频次采样有什么方法吗？谢谢

Start by reading the implementations of sample_node and sample_node_with_src mentioned in the issue, then trace how negative samples are selected and where node frequencies are available. The issue does not name files, tests, or a defined completion criterion; clarify the intended frequency distribution and expected API behavior before estimating or implementing the change.

Written by the indexing model from the issue text.