Coordinates and shower axis

[anelles]

How to store arrival directions. Just zenith and azimuth is confusing.

At least we need:

-- signal_arrival_zenith
-- signal_arrival_azimuth
-- particle_arrival_zenith
-- particle_arrival_azimuth
-- signal_propagation_azimuth
-- signal_propagation_zenith
-- particle_propagation_azimuth
-- particle_propagation_zenith

and then twice for simulated and reconstructed. This could be stored as just two vectors with getters and setters.

[cg-laser]

we could add a getter and setter for each 'direction' but that would make the code more difficult, i.e. we need to write a bunch of setter/getter function, serialize/deserialize everyting properly...
Instead I propose to stick to just zenith and azimuth angles and save them in the parameter storage class. These parameters need to be well defined in the parameter storage file.

Furthermore, we agreed on saving always the arrival direction to avoid confusions.

To get the verctor in cartesian coordinates, one can use the helper function from radiotools:

from radiotools import helper
helper.spherical_to_cartesian(zenith, azimuth)

[anelles]

Fine with me. I just wanted the decision to only use the arrival direction to be properly documented.

The next question is what to store from sims where. If we have two pulses in a trace they will have different arrival directions (i.e. you need different antenna angles). Any thoughts on how to save that?