Revert "Access of numpy-Arrays changed. Now without .index()"

This reverts commit b2e5fbb80ca4cd110a7354efa7a2aae356d9604c.
Revert "Revert "Access of numpy-Arrays changed. Now without .index()""

This reverts commit f5f74d12c0e20cca00bd900abfbd2fed5db2b4ae.
Revert the windows merge fuck up.

Turns out, it was kinda easy doing, only with git checkout :-)