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Fix handling of SPH arrays and database changes between versions #88

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Merged
codie3611 merged 2 commits into from
Aug 30, 2025
Merged

Fix handling of SPH arrays and database changes between versions #88

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bfc132e
fix: Correctly read SPH data
DCHartlen Aug 30, 2025
0cf6444
fix: Handle inconsistant SPH header between versions
DCHartlen Aug 30, 2025
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77 changes: 42 additions & 35 deletions src/lasso/dyna/d3plot.py
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Original file line number Diff line number Diff line change
Expand Up @@ -1285,7 +1285,8 @@ class SphSectionInfo:
has_material_density: bool = False
has_internal_energy: bool = False
has_n_affecting_neighbors: bool = False
has_strain_and_strainrate: bool = False
has_strain: bool = False
has_strainrate: bool = False
has_true_strains: bool = False
has_mass: bool = False
n_sph_history_vars: int = 0
Expand Down Expand Up @@ -2157,7 +2158,15 @@ def _read_fluid_material_data(self):
LOGGER.debug("_read_fluid_material_data end at byte %d", self.geometry_section_size)

def _read_sph_element_data_flags(self):
"""Read the sph element data flags"""
"""Read the sph element data flags

The LS-DYNA database has some undocumented behaviour between older and newer
versions that impact how SPH header data is handled. The manual idnicates that
isphfg(1) should always be 11. However, in versions of LS-DYNA newer than R9,
isphfg(1) can be either 10 or 11 as history variables are handled differently.
Special handling was needed to ensure that old behaviour broken while handling
this undocumented change.
"""

if not self._buffer:
return
Expand Down Expand Up @@ -2193,17 +2202,16 @@ def _read_sph_element_data_flags(self):
self._sph_info.has_material_density = sph_header_data["isphfg6"] != 0
self._sph_info.has_internal_energy = sph_header_data["isphfg7"] != 0
self._sph_info.has_n_affecting_neighbors = sph_header_data["isphfg8"] != 0
self._sph_info.has_strain_and_strainrate = sph_header_data["isphfg9"] != 0
self._sph_info.has_strain = sph_header_data["isphfg9"] != 0
self._sph_info.has_strainrate = sph_header_data["isphfg9"] > 6
self._sph_info.has_true_strains = sph_header_data["isphfg9"] < 0
self._sph_info.has_mass = sph_header_data["isphfg10"] != 0
self._sph_info.n_sph_history_vars = sph_header_data["isphfg11"]

if self._sph_info.n_sph_array_length != 11:
msg = (
"Detected inconsistency: "
f"isphfg = {self._sph_info.n_sph_array_length} but must be 11."
)
raise RuntimeError(msg)
# If isphfg1 = 10, then there are no history variables by default and isphfg11
# is filled with junk data that causes issues calculating n_sph_vars below
if sph_header_data["isphfg1"] == 10:
self._sph_info.n_sph_history_vars = 0
else:
self._sph_info.n_sph_history_vars = sph_header_data["isphfg11"]

self._sph_info.n_sph_vars = (
sph_header_data["isphfg2"]
Expand All @@ -2215,7 +2223,7 @@ def _read_sph_element_data_flags(self):
+ sph_header_data["isphfg8"]
+ abs(sph_header_data["isphfg9"])
+ sph_header_data["isphfg10"]
+ sph_header_data["isphfg11"]
+ self._sph_info.n_sph_history_vars
+ 1
) # material number

Expand Down Expand Up @@ -5082,13 +5090,17 @@ def _read_states_sph(self, state_data: np.ndarray, var_index: int, array_dict: d

# extract data
try:
sph_data = state_data[:, var_index : var_index + n_particles * n_variables]
sph_data = state_data[:, var_index : var_index + n_particles * n_variables].reshape((
n_states,
n_particles,
n_variables,
))

i_var = 1

# deletion
try:
array_dict[ArrayType.sph_deletion] = sph_data[:, 0] < 0
array_dict[ArrayType.sph_deletion] = sph_data[:, :, 0] < 0
except Exception:
trb_msg = traceback.format_exc()
msg = "A failure in %s was caught:\n%s"
Expand All @@ -5097,7 +5109,7 @@ def _read_states_sph(self, state_data: np.ndarray, var_index: int, array_dict: d
# particle radius
if info.has_influence_radius:
try:
array_dict[ArrayType.sph_radius] = sph_data[:, i_var]
array_dict[ArrayType.sph_radius] = sph_data[:, :, i_var]
except Exception:
trb_msg = traceback.format_exc()
msg = "A failure in %s was caught:\n%s"
Expand All @@ -5108,7 +5120,7 @@ def _read_states_sph(self, state_data: np.ndarray, var_index: int, array_dict: d
# pressure
if info.has_particle_pressure:
try:
array_dict[ArrayType.sph_pressure] = sph_data[:, i_var]
array_dict[ArrayType.sph_pressure] = sph_data[:, :, i_var]
except Exception:
trb_msg = traceback.format_exc()
msg = "A failure in %s was caught:\n%s"
Expand All @@ -5119,20 +5131,18 @@ def _read_states_sph(self, state_data: np.ndarray, var_index: int, array_dict: d
# stress
if info.has_stresses:
try:
array_dict[ArrayType.sph_stress] = sph_data[
:, i_var : i_var + n_particles * 6
].reshape((n_states, n_particles, 6))
array_dict[ArrayType.sph_stress] = sph_data[:, :, i_var : i_var + 6]
except Exception:
trb_msg = traceback.format_exc()
msg = "A failure in %s was caught:\n%s"
LOGGER.warning(msg, "_read_states_sph, pressure", trb_msg)
finally:
i_var += 6 * n_particles
i_var += 6

# eff. plastic strain
if info.has_plastic_strain:
try:
array_dict[ArrayType.sph_effective_plastic_strain] = sph_data[:, i_var]
array_dict[ArrayType.sph_effective_plastic_strain] = sph_data[:, :, i_var]
except Exception:
trb_msg = traceback.format_exc()
msg = "A failure in %s was caught:\n%s"
Expand All @@ -5143,7 +5153,7 @@ def _read_states_sph(self, state_data: np.ndarray, var_index: int, array_dict: d
# density
if info.has_material_density:
try:
array_dict[ArrayType.sph_density] = sph_data[:, i_var]
array_dict[ArrayType.sph_density] = sph_data[:, :, i_var]
except Exception:
trb_msg = traceback.format_exc()
msg = "A failure in %s was caught:\n%s"
Expand All @@ -5154,7 +5164,7 @@ def _read_states_sph(self, state_data: np.ndarray, var_index: int, array_dict: d
# internal energy
if info.has_internal_energy:
try:
array_dict[ArrayType.sph_internal_energy] = sph_data[:, i_var]
array_dict[ArrayType.sph_internal_energy] = sph_data[:, :, i_var]
except Exception:
trb_msg = traceback.format_exc()
msg = "A failure in %s was caught:\n%s"
Expand All @@ -5165,42 +5175,39 @@ def _read_states_sph(self, state_data: np.ndarray, var_index: int, array_dict: d
# number of neighbors
if info.has_n_affecting_neighbors:
try:
array_dict[ArrayType.sph_n_neighbors] = sph_data[:, i_var]
array_dict[ArrayType.sph_n_neighbors] = sph_data[:, :, i_var]
except Exception:
trb_msg = traceback.format_exc()
msg = "A failure in %s was caught:\n%s"
LOGGER.warning(msg, "_read_states_sph, n_neighbors", trb_msg)
finally:
i_var += 1

# strain and strainrate
if info.has_strain_and_strainrate:
# strain
if info.has_strain:
try:
array_dict[ArrayType.sph_strain] = sph_data[
:, i_var : i_var + n_particles * 6
].reshape((n_states, n_particles, 6))
array_dict[ArrayType.sph_strain] = sph_data[:, :, i_var : i_var + 6]
except Exception:
trb_msg = traceback.format_exc()
msg = "A failure in %s was caught:\n%s"
LOGGER.warning(msg, "_read_states_sph, strain", trb_msg)
finally:
i_var += 6 * n_particles
i_var += 6

if info.has_strainrate:
try:
array_dict[ArrayType.sph_strainrate] = sph_data[
:, i_var : i_var + n_particles * 6
].reshape((n_states, n_particles, 6))
array_dict[ArrayType.sph_strainrate] = sph_data[:, :, i_var : i_var + 6]
except Exception:
trb_msg = traceback.format_exc()
msg = "A failure in %s was caught:\n%s"
LOGGER.warning(msg, "_read_states_sph, strainrate", trb_msg)
finally:
i_var += 6 * n_particles
i_var += 6

# mass
if info.has_mass:
try:
array_dict[ArrayType.sph_mass] = sph_data[:, i_var]
array_dict[ArrayType.sph_mass] = sph_data[:, :, i_var]
except Exception:
trb_msg = traceback.format_exc()
msg = "A failure in %s was caught:\n%s"
Expand Down