Read a result file

pyvista_frd.read() returns a pyvista.UnstructuredGrid. Nodal results are stored as point data and work with standard PyVista filters.

The file here is a cantilever: 600 linear hexahedra fixed at one end and loaded at the other, solved by CalculiX 2.22.

from pathlib import Path

import pyvista as pv

import pyvista_frd

# Sphinx-Gallery runs this file from ``doc/examples``.
DATA = Path('../_data').resolve()

Read the first result step.

mesh = pyvista_frd.read(DATA / 'cantilever.frd')
mesh

UnstructuredGrid (0x7f9965d48100)
  N Cells:    600
  N Points:   900
  X Bounds:   0.000e+00, 1.500e+02
  Y Bounds:   0.000e+00, 2.000e+01
  Z Bounds:   0.000e+00, 2.000e+01
  N Arrays:   15

UnstructuredGrid 900 points 600 cells 245 KiB

Bounds⧉X [0.000e+00, 1.500e+02]Y [0.000e+00, 2.000e+01]Z [0.000e+00, 2.000e+01]

• Point Data: (15)
  DISP active
  • original_node_ids⧉
    scalar
    int32
    [1.000e+00, 9.000e+02]
  • DISP⧉
    3 comp
    float64
    [-2.308e-02, 2.291e-03]
    active
  • STRESS⧉
    6 comp
    float64
    [-8.138e+00, 8.138e+00]
  • STRESS_Mises⧉
    scalar
    float64
    [2.222e-01, 5.980e+00]
  • STRESS_sgMises⧉
    scalar
    float64
    [-5.980e+00, 5.980e+00]
  • STRESS_PS3⧉
    scalar
    float64
    [-8.535e+00, 3.091e+00]
  • STRESS_PS2⧉
    scalar
    float64
    [-3.488e+00, 3.488e+00]
  • STRESS_PS1⧉
    scalar
    float64
    [-3.091e+00, 8.535e+00]
  • TOSTRAIN⧉
    6 comp
    float64
    [-2.879e-05, 2.879e-05]
  • TOSTRAIN_Mises⧉
    scalar
    float64
    [9.169e-07, 2.468e-05]
  • TOSTRAIN_sgMises⧉
    scalar
    float64
    [-2.468e-05, 2.468e-05]
  • TOSTRAIN_PS3⧉
    scalar
    float64
    [-3.125e-05, -3.093e-07]
  • TOSTRAIN_PS2⧉
    scalar
    float64
    [-8.168e-06, 8.168e-06]
  • TOSTRAIN_PS1⧉
    scalar
    float64
    [3.093e-07, 3.125e-05]
  • ERROR⧉
    scalar
    float64
    [1.617e+01, 9.405e+01]

DISP and STRESS come from the file. The reader derives the _Mises and _PS* arrays from the stress tensor.

for name in mesh.point_data:
    array = mesh.point_data[name]
    print(f'{name:16s} {array.shape}')

original_node_ids (900,)
DISP             (900, 3)
STRESS           (900, 6)
STRESS_Mises     (900,)
STRESS_sgMises   (900,)
STRESS_PS3       (900,)
STRESS_PS2       (900,)
STRESS_PS1       (900,)
TOSTRAIN         (900, 6)
TOSTRAIN_Mises   (900,)
TOSTRAIN_sgMises (900,)
TOSTRAIN_PS3     (900,)
TOSTRAIN_PS2     (900,)
TOSTRAIN_PS1     (900,)
ERROR            (900,)

Plot displacement on the deformed mesh. A factor of 200 makes the small displacement visible.

warped = mesh.warp_by_vector('DISP', factor=200)

pl = pv.Plotter(window_size=(1000, 380))
pl.add_mesh(warped, scalars='DISP', component=2, cmap='coolwarm', show_edges=True)
pl.add_mesh(mesh, style='wireframe', color='grey', opacity=0.3)
pl.camera.tight(padding=0.05, adjust_render_window=False, view='xz')
pl.show()

Apply a standard PyVista clip to the same mesh.

pl = pv.Plotter(window_size=(1000, 380))
pl.add_mesh(warped.clip('y'), scalars='STRESS_Mises', cmap='inferno', show_edges=True)
pl.camera.tight(padding=0.05, adjust_render_window=False, view='xz')
pl.show()