[WIP] OpenPMD frontend update

pyproject.toml

@@ -118,7 +118,7 @@ http-stream = ["requests>=2.20.0"]
 idefix = ["yt_idefix[HDF5]>=2.3.0"] # externally packaged frontend
 moab = ["yt[HDF5]"]
 nc4-cm1 = ["yt[netCDF4]"]
-open-pmd = ["yt[HDF5]"]
+open-pmd = ["yt[openpmd_api]"]
 owls = ["yt[HDF5]"]
 owls-subfind = ["yt[HDF5]"]
 ramses = ["yt[Fortran]"]

yt/frontends/open_pmd/api.py

@@ -1,4 +1,4 @@
 from . import tests
 from .data_structures import OpenPMDDataset, OpenPMDGrid, OpenPMDHierarchy
 from .fields import OpenPMDFieldInfo
-from .io import IOHandlerOpenPMDHDF5
+from .io import IOHandlerOpenPMD

yt/frontends/open_pmd/fields.py

@@ -5,7 +5,6 @@
 from yt.frontends.open_pmd.misc import is_const_component, parse_unit_dimension
 from yt.units.yt_array import YTQuantity
 from yt.utilities.logger import ytLogger as mylog
-from yt.utilities.on_demand_imports import _h5py as h5py
 from yt.utilities.physical_constants import mu_0, speed_of_light
 
 
@@ -141,20 +140,19 @@ class OpenPMDFieldInfo(FieldInfoContainer):
 
  def __init__(self, ds, field_list):
  f = ds._handle
- bp = ds.base_path
- mp = ds.meshes_path
- pp = ds.particles_path
 
  try:
- fields = f[bp + mp]
- for fname in fields.keys():
+ fields = f.meshes
+ for fname in list(fields):
  field = fields[fname]
- if isinstance(field, h5py.Dataset) or is_const_component(field):
+ if len(list(field)) == 1 or is_const_component(field):
  # Don't consider axes.
  # This appears to be a vector field of single dimensionality
- ytname = str("_".join([fname.replace("_", "-")]))
+ ytname = str(
+ "_".join([fname.replace("_", "-")])
+ ) # doesn't do anything for us
  parsed = parse_unit_dimension(
- np.asarray(field.attrs["unitDimension"], dtype="int64")
+ np.asarray(field.unit_dimension, dtype="int64")
  )
  unit = str(YTQuantity(1, parsed).units)
  aliases = []
@@ -164,10 +162,10 @@ def __init__(self, ds, field_list):
  self._mag_fields.append(ytname)
  self.known_other_fields += ((ytname, (unit, aliases, None)),)
  else:
- for axis in field.keys():
+ for axis in list(field):
  ytname = str("_".join([fname.replace("_", "-"), axis]))
  parsed = parse_unit_dimension(
- np.asarray(field.attrs["unitDimension"], dtype="int64")
+ np.asarray(field.unit_dimension, dtype="int64")
  )
  unit = str(YTQuantity(1, parsed).units)
  aliases = []
@@ -182,29 +180,28 @@ def __init__(self, ds, field_list):
  pass
 
  try:
- particles = f[bp + pp]
- for pname in particles.keys():
+ particles = f.particles
+ for pname in list(particles):
  species = particles[pname]
- for recname in species.keys():
+ for recname in list(species):
  try:
  record = species[recname]
- parsed = parse_unit_dimension(record.attrs["unitDimension"])
+ parsed = parse_unit_dimension(record.unit_dimension)
  unit = str(YTQuantity(1, parsed).units)
+
  ytattrib = str(recname).replace("_", "-")
  if ytattrib == "position":
  # Symbolically rename position to preserve yt's
  # interpretation of the pfield particle_position is later
  # derived in setup_absolute_positions in the way yt expects
  ytattrib = "positionCoarse"
- if isinstance(record, h5py.Dataset) or is_const_component(
- record
- ):
+ if len(list(record)) == 1 or is_const_component(record):
  name = ["particle", ytattrib]
  self.known_particle_fields += (
  (str("_".join(name)), (unit, [], None)),
  )
  else:
- for axis in record.keys():
+ for axis in list(record):
  aliases = []
  name = ["particle", ytattrib, axis]
  ytname = str("_".join(name))