This tutorial requires that the WavefrontPropaGator (WPG) package is installed.

Since the WPG package is a requirement of phenom, we encourage you to install WPG if you wish to use the phenom WPG interface.

You can check your installation of WPG, and the subsequent requirement of SRW as :

import wpg
from wpg import srwlpy as srwl

Interfacing with WavefrontPropaGator (WPG)

The phenom.wpg script provides the functionalities require to convert the source wavefront files to the WavefrontPropaGator (WPG) format.

Load the source generated in the any of the previous tutorials:

Converting Source Data to a WPG Wavefront

The ‘wpg_converter’ writes each key of the source to a seperate .h5 file that is WPG readable

from phenom.wpg import wpg_converter
save_loc = "./sase_field.h5" ### master .h5
key =  "pulse000" ### pulse_id

wfr = wpg_converter(save_loc, key = key)
wfr.store_hdf5("./wpg_sase.h5")

Traceback (most recent call last):

  Cell In[2], line 5
    wfr = wpg_converter(save_loc, key = key)

  File ~/phenom/phenom/wpg.py:41 in wpg_converter
    with h5.File(save_loc, mode = 'r') as hf:

  File ~/miniconda3/envs/mid/lib/python3.12/site-packages/h5py/_hl/files.py:562 in __init__
    fid = make_fid(name, mode, userblock_size, fapl, fcpl, swmr=swmr)

  File ~/miniconda3/envs/mid/lib/python3.12/site-packages/h5py/_hl/files.py:235 in make_fid
    fid = h5f.open(name, flags, fapl=fapl)

  File h5py/_objects.pyx:54 in h5py._objects.with_phil.wrapper

  File h5py/_objects.pyx:55 in h5py._objects.with_phil.wrapper

  File h5py/h5f.pyx:102 in h5py.h5f.open

FileNotFoundError: [Errno 2] Unable to synchronously open file (unable to open file: name = './sase_field.h5', errno = 2, error message = 'No such file or directory', flags = 0, o_flags = 0)

With the pulse wavefront now WPG readable, we can apply in to wavefront propagation simulations:

from wpg.beamline import Beamline
from wpg.optical_elements import Drift

from wpg.wpg_uti_wf import plot_intensity_map

wfr.load_hdf5("./wpg_sase.h5")

bl = Beamline()
bl.append(Drift(10), propagation_parameters = [0, 0, 1, 0, 0, 2, 1.0, 2, 1.0, 0, 0, 0])
bl.propagate(wfr)

plot_intensity_map(wfr)

Converting Multiple Pulses to WPG Wavefronts

We can convert all pulses in a source .h5 to WPG readable wavefronts by iterating of the source .h5:

import h5py as h5
from phenom.wpg import wpg_converter

with h5.File(save_loc) as hf:

    for key in list(hf.keys()):
        wfr = wpg_converter(save_loc, key = key)
        wfr.store_hdf5("./wpg_sase_{}.h5".format(key))

import numpy as np
from matplotlib import pyplot as plt
from wpg.wpg_uti_wf import get_intensity_on_axis

[E, spectrum] = get_intensity_on_axis(wfr).T

fig, ax = plt.subplots(1,1,figsize = (5,5))

ax.plot(E, spectrum)
ax.set_xlabel("Energy (keV)")
ax.set_ylabel("Intensity (a.u.)")