Pfthb

I am trying to use TemporaryFile. here is the code snippet.

from tempfile import TemporaryFile
outfile = TemporaryFile(dir='./')
np.save(outfile, np.arange(9))
outfile.close()

I print outfile.name, then I got 62, I didn't find anything with a name 62. Actually I got nothing in specified directory.

My question is, where does TemporaryFile save file, and how to specify a directory for TemporaryFile() method.

You probably want NamedTemporaryFile instead of TemporaryFile. TemporaryFile can be created in such a way as to not be visible on the normal filesystem, whereas NamedTemporaryFile is guaranteed to be visible.

From the NamedTemporaryFile docs:

This function operates exactly as TemporaryFile() does, except that the file is guaranteed to have a visible name in the file system (on Unix, the directory entry is not unlinked). That name can be retrieved from the name attribute of the returned file-like object...

So just replace all mentions of TemporaryFile in your code with NamedTemporaryFile and then everything should work like you expect. Be aware though that a NamedTemporaryFile will still be removed from your filesystem once you close() it.