在Tensorflow中，如何将tf.gather（）用于最后一个维度？ [英] In Tensorflow, how to use tf.gather() for the last dimension?

问题描述

我正在尝试收集最后张量的张量切片，以实现层之间的部分连接。因为输出张量的形状是 [batch_size，h，w，深度] ，所以我想根据最后一个维度选择切片，例如

I am trying to gather slices of a tensor in terms of the last dimension for partial connection between layers. Because the output tensor's shape is [batch_size, h, w, depth], I want to select slices based on the last dimension, such as

# L is intermediate tensor
partL = L[:, :, :, [0,2,3,8]]

但是， tf.gather（L，[0，2,3,8]）似乎仅适用于第一个维度（对吗？）有人可以告诉我该怎么做吗？

However, tf.gather(L, [0, 2,3,8]) seems to only work for the first dimension (right?) Can anyone tell me how to do it?

推荐答案

此处有一个跟踪错误可支持此用例： https://github.com/tensorflow/tensorflow/issues/206

There's a tracking bug to support this use-case here: https://github.com/tensorflow/tensorflow/issues/206

您可以：

1. 对矩阵进行转置，以便首先收集要收集的维数（转置非常昂贵）

1. transpose your matrix so that dimension to gather is first (transpose is expensive)

将张量重整为1d（重整便宜），然后在线性索引处将收集列的索引转换为单个元素索引的列表，然后重整

reshape your tensor into 1d (reshape is cheap) and turn your gather column indices into a list of individual element indices at linear indexing, then reshape back

这篇关于在Tensorflow中，如何将tf.gather（）用于最后一个维度？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！