Fix output csv writing in patch_manager

[katesedykh]

If you have several input images and use function mine_patches, the header will be added to csv file for each one. Check if file is empty or header is already there.

[grenkoca]

Thank you for your feedback @katesedykh. We recently merged some changes (See: PR #17) to resolve this issue, and hopefully they should work. Could you update your version of OPM to development using the following commands:

git clone https://github.com/CBICA/OPM.git
cd OPM/
conda create -p ./venv python=3.8.12 -y
conda activate ./venv
pip install .

Then try running your command again. If that doesn't work, it would be helpful if you could share the code/command you're using so we can reproduce the issue.

Thank you!
Caleb

[grenkoca]

Closing this thread as we patched and got no response