从目录中提取有限的文件，然后将其插入另一个目录

Question

我的目录包含80.000个图像 ，我想使用Bash命令将该目录中的30.000个图像随机插入另一个目录。

Answer 1

假设您位于80000张图片所在的目录中，而另一个目录称为target，则此目录应该有效：

ls | shuf | head -n 30000 | xargs -i cp "{}" target/.

Answer 2

While the provided answer is correct shuf is not installed on all systems so you might consider to use sort -R instead. I quote the man page:

Sort by a random order. This is a random permutation of the inputs except that the equal keys sort together. It is implemented by hashing the input keys and sorting the hash values. The hash function is chosen randomly. The hash function is randomized by /dev/random content, or by file content if it is specified by --random-source. Even if multiple sort fields are specified, the same random hash function is used for all of them.

As long as you do not have any duplicates (exactly the same file just with a different name) and you do not want to install shuf or any other tool you can use this to get a 'random' sort.

ls | sort -R | tail -n 30000 | xargs -I "{}" cp "{}" ./target