Features of propertylib

Section author: Florian Zill (Helmholtz Centre for Environmental Research GmbH - UFZ)

propertylib provides a common interface for other modules to structure reading, conversion and output of mesh data.

import matplotlib.pyplot as plt
import numpy as np
import pandas as pd

from ogstools.propertylib import presets

There are some predefined default properties:

tab = pd.DataFrame(presets.all_properties).set_index("output_name")
tab["type"] = [p.type_name for p in presets.all_properties]
tab.drop(["func", "bilinear_cmap"], axis=1).sort_values(["mask", "data_name"])

	data_name	data_unit	output_unit	mask	categoric	type
output_name
MaterialIDs	MaterialIDs				True	Scalar
NodalForces	NodalForces			displacement_active	False	Vector
displacement	displacement	m	m	displacement_active	False	Vector
strain	epsilon		percent	displacement_active	False	Matrix
effective_pressure	sigma	Pa	MPa	displacement_active	False	Scalar
QP_ratio	sigma	Pa	percent	displacement_active	False	Scalar
stress	sigma	Pa	MPa	displacement_active	False	Matrix
von_Mises_stress	sigma	Pa	MPa	displacement_active	False	Scalar
MassFlowRate	MassFlowRate			pressure_active	False	Scalar
pore_pressure	pressure	Pa	MPa	pressure_active	False	Scalar
hydraulic_height	pressure	m	m	pressure_active	False	Scalar
darcy_velocity	velocity	m/s	m/s	pressure_active	False	Vector
HeatFlowRate	HeatFlowRate			temperature_active	False	Scalar
temperature	temperature	K	°C	temperature_active	False	Scalar

You can access properties either form the entire collection or from a subset which only contains properties available to a specific OGS process. Calling a property converts the argument from data_unit to output_unit and applies a function if specified.

print(presets.temperature(273.15))  # access from the entire collection
print(presets.strain(0.01))  # access from Mechanics collection

0 °C
1 %

VectorProperties and MatrixProperties contain other Properties which represent the result of an applied function on itself. Components can be accessed with brackets. VectorProperties should be of length 2 or 3 corresponding to the dimension. MatrixProperties likewise should be of length 4 [xx, yy, zz, xy] or 6 [xx, yy, zz, xy, yz, xz].

Element 1 (counting from 0) of a 3D displacement vector:

print(presets.displacement[1]([0.01, 0.02, 0.03]))

0.02 m

Magnitude of a 2D displacement vector from:

print(presets.displacement.magnitude([0.03, 0.04]))

0.05 m

Log of Magnitude of a 2D velocity vector from the Hydraulics collection:

print(presets.velocity.log_magnitude(np.sqrt([50, 50])))

1

Magnitude and trace of a 3D strain matrix:

eps = np.array([1, 3, 9, 1, 2, 2]) * 1e-2
print(presets.strain.magnitude(eps))
print(presets.strain.trace(eps))

10 %
13 %

You can change the attributes of the defaults. For example for temperature from the Thermal Collection from the default output_unit °C to °F:

temp = np.linspace(273.15, 373.15, 10)
fig, axs = plt.subplots(2)
axs[0].plot(presets.temperature(temp), color="r")
temperature_F = presets.temperature.replace(output_unit="°F")
axs[1].plot(temperature_F(temp), color="b")
fig.show()

/workspaces/tools/.venv-devcontainer/lib/python3.9/site-packages/matplotlib/cbook/__init__.py:1345: UnitStrippedWarning: The unit of the quantity is stripped when downcasting to ndarray.
  return np.asarray(x, float)