The derivatives are not copied after the `preprocess_segment.sh` runs

[rohanbanerjee]

The line does not copy the derivatives after calculating the derivatives. This has to be fixed.

[jcohenadad]

ok-- it could be actually fine to not copy the derivatives as long as they are fetched later on when checking their existence-- the problem is, the check is performed LOCALLY (ie: in the output processed data folder):

https://github.com/neuropoly/template/blob/16fa7569dd37a0fa54b4f3a35be3d7e7cc187205/preprocess_segment.sh#L70C4-L70C4

whereas in other projects, eg spine generic, it is done using the abs input path:

https://github.com/spine-generic/spine-generic/blob/c8c8408715f101414ca08c6bcf29a5d5b87df90a/process_data.sh#L89C12-L89C12

so, to conclude:

• we SHOULD NOT copy the derivatives to the output data
• but, we SHOULD check the presence of the derivatives in the source folder