How can I import CSV files in Sagemath Cloud?

edit

I was trying out Sagemath Cloud. Looks great, good job. But I have a problem because I can't figure out how to import CSV files with data.

I am using R (%default_mode r) to do some basic statistics and stuff in a worksheet. I already have the script working on my local machine, but I wanted to try it in the Cloud too.

What I did was that I drag-and-dropped a couple of CSV files into a project. Seems to work fine; the files appear in the drag-and-drop area, and a progress indicator goes to full and then a green check-mark appears. But after that, the files are not present in the Files section, there is only my worksheet. In the Log section, there is only mention of me opening the worksheet, it says nothing about successfully uploading files. When I try to run an import command in the worksheet, I get "No such file or directory".

The import command I used:

data <- read.csv("filename.csv", header=TRUE, sep=';')

EDIT:

This question has an answer for how to do it in Python. But I am doing it from R, and I reckon the python function os.environ() is not available.

EDIT 2:

If I go to the terminal line under Files and type "ls -A" I can get a full list of files in my project, but the CSV files that I dragged-and-dropped are not in the list.