function, as dynamically assigned variables are missing otherwise

bugfix: unmasking reinjected the new (i.e. nan) instead of the old values (this should have been caught by a test)

a implementation with a finally clause would be possible, but make the code look like spaghetti. :P

i removed the setup of the logging module from the core. It interferes
with the needs of the user of the lib (saqc). eg. Messages are double
printed or not at all.

>> It is strongly advised that you do not add any handlers other than
>> NullHandler to your library’s loggers. [...]
from https://docs.python.org/3/howto/logging.html

we might add a defalutLoggingSetup(log_level='INFO') function or similar in future,
to ease the setup the logging.

Data that is flagger.BAD is masked by default.
One can pass a flag or a list-like to the param to_mask to control the behavior.
Pass an empty list to disable masking.
Nevertheless IFF the index changed the masked data is not restored.
Also flags are NOT restored IFF they considered _flagged_ before the func call, but not afterwards anymore.
Also any data that is set on masked locations is not overwritten by unmasking.

`write_back` parameter in `getResult`. While the previous
version worked in the sense, that it allowed to `save` computations
already done, I disliked the state-changing behaviour of that
implemetation. Now we have a way to realize the registered
test functions into a new `SaQC` without modifying the old one and
don't violate the functional interface of the `SaQC`-Objects
any more.

the actually needed charactersitics. The old check was forcing equal
columns on `flagger.flags` and `data`, a condition we don't need to
be satisfied and don't satisfy during the lifetime of `SaQC`-Object
either. The new check only guarantees, that all columns in `data`
have a counterpart in `flagger.flags` but allow the latter to have
additional columns as well.

David Schäfer authored 4 years ago and Bert Palm committed 4 years ago

  - most things work
  - all remaining things are solveable
  - a lot of cleanup ahead