Ray.get with remote function doesn't work for string variables

Ray Core
1

Hello,
I’m trying to use ray.get(classifier.remote(i, x,) where i and x are file paths (string variables). For some reason, the Classifier function isn’t picking up the string variables to open the files. Is it normal?
Please help!

2

@sangcho
Please help!

3

Can you give me a little bit more context? Like how is your Classifier function looking like and what’s the error message you are seeing?

4

@ray.remote
def classifier(i,x):
x = pd.read_csv(i)
return x

and error says “cannot find file”

5

but if I do without ray, it is working fine :frowning:

6

Are you using a cluster mode? It simply means your file cannot be found from the place where the worker is executed. You can try;

@ray.remote
def classifier(i, x):
    import os
    print(os.getcwd())
    x = pd.read_csv(i)
    return x
7

Ray workers are not executed at the same directory location as your driver, so you should pass the absolute path instead, and I think it will work if you are using a single node. If you are using a cluster mode, you need to make sure the file exists in the worker node.

8

ohh okay. I’ll try that. Thanks!

9

Looks like the path is where the script is located at… and not the working directory it is supposed to go to :frowning:

10

Great! Did you fix the issue then?

11

yes. I’m using os.chdir('path') within the function and it works!
Thanks!

1 Like
12

I think it’s worth documenting it somewhere.
#rayforlife

13

Yeah good idea! (Also, feel free to submit a contribution PR if you’d like to!)