Change _libwarpx.py functions to LibWarpX class methods (#2696)

* Initial attempt at moving function into LibWarpX

* Bugfix - undefined structs in get_particle_theta

This is untested, identified by IDE/visual inspection only

* Unify newlines

* Delete libwarpx.clight (duplicated picmi.py)

See picmi.constants.c

* Change function descriptive comment to docstring

Also remove extra newline in __init__ beginning.

* Replace pywarpx/_libwarpx calls appropriately

* Fix atexit register of finalize function

* Reorder WarpX.py imports for pre-commit

* Use picmi.Simulation.extension = libwarpx alias

This will hopefully preempt user script changes if we restructure things
to allow multiple WarpX runs to be done within a single Python script.

* Fix libwarpx ref in WarpX.getProbLo/getProbHi

* Update get_particle_boundary_buffer doc reference

1 files changed, 4 insertions, 5 deletions

diff --git a/Examples/Modules/ParticleBoundaryProcess/PICMI_inputs_reflection.py b/Examples/Modules/ParticleBoundaryProcess/PICMI_inputs_reflection.py
index c9903ad22..d7d023ef6 100755
--- a/Examples/Modules/ParticleBoundaryProcess/PICMI_inputs_reflection.py
+++ b/Examples/Modules/ParticleBoundaryProcess/PICMI_inputs_reflection.py
@@ -2,7 +2,6 @@
 #
 # --- Input file to test particle reflection off an absorbing boundary
 
-import pywarpx
 from pywarpx import picmi
 
 constants = picmi.constants
@@ -115,20 +114,20 @@ sim.step(max_steps)
 # buffer functions as intended
 ################################################
 
-n = pywarpx.get_particle_boundary_buffer_size("electrons", 'z_hi')
+n = sim.extension.get_particle_boundary_buffer_size("electrons", 'z_hi')
 print("Number of electrons in upper buffer:", n)
 assert n == 63
 
-n = pywarpx.get_particle_boundary_buffer_size("electrons", 'z_lo')
+n = sim.extension.get_particle_boundary_buffer_size("electrons", 'z_lo')
 print("Number of electrons in lower buffer:", n)
 assert n == 67
 
-scraped_steps = pywarpx.get_particle_boundary_buffer("electrons", 'z_hi', 'step_scraped', 0)
+scraped_steps = sim.extension.get_particle_boundary_buffer("electrons", 'z_hi', 'step_scraped', 0)
 for arr in scraped_steps:
     # print(arr)
     assert all(arr == 4)
 
-scraped_steps = pywarpx.get_particle_boundary_buffer("electrons", 'z_lo', 'step_scraped', 0)
+scraped_steps = sim.extension.get_particle_boundary_buffer("electrons", 'z_lo', 'step_scraped', 0)
 for arr in scraped_steps:
     # print(arr)
     assert all(arr == 8)