Initializing PICMI real component

[archermarx]

Hi,

I'd like to add a real component to a particle species. However, trying to access this component causes WarpX to segfault. Here's an example:

# Define my particle container and the component
elec_wrapper = particle_containers.ParticleContainerWrapper('electrons')
elec_wrapper.add_real_comp('my_comp')

# Trying to initialize this component to zero at the first timestep
def initialize_comp():
    x = elec_wrapper.get_particle_arrays('my_comp')
    for xi in x:
        xi[:] = 0.0

# Install callback
callbacks.installafterinit(initialize_comp)

What am I doing wrong?

[roelof-groenewald]

Hi Thomas. The reason you are encountering a segfault is because the particle containers are not initialized yet when you query WarpX for it via elec_wrapper = particle_containers.ParticleContainerWrapper('electrons'). This call needs to happen after WarpX has been initialized through simulation.initialize_warpx().
Take a look at the example at https://github.com/ECP-WarpX/WarpX/blob/development/Examples/Tests/particle_data_python/PICMI_inputs_2d.py for how this can be achieved.

Please let us know if you have further questions.

[archermarx]

Yep, that was it. Thank you!