Please describe the issue clearly and attach any relevant files e.g. STLs
Please add a test if relevant. If it is a bug fix, create a test which would fail before the fix and passes after the fix. If it is a feature, add a test which shows the feature works. If the feature requires explanation, please add documentation to the README.md file. Finally, please run the test suite to make sure nothing broke. The last regression test takes a long time (~24 minutes) so don't run it while developing, just once at the end.