Visualize SG Data

SGIO can render cross-section geometry, homogenized properties, and merged blade meshes. Three backends are used, each suited to a different job.

Backend	Use for	Dependency
matplotlib	Static figures for reports	required
plotly	Interactive HTML, large meshes	required
PyVista / VTK	3D inspection, ParaView export	optional (sgio[pyvista])

Plot a Single Cross-Section

sgio.plot_sg_2d() draws the mesh of a sgio.StructureGene, and sgio.plot_model_2d() draws the quantities carried by a homogenized model — the mass center, shear center, and principal bending axes. They are separate functions that compose by sharing one matplotlib axes:

import matplotlib.pyplot as plt
import sgio

cs = sgio.read('cross_section.sg', 'vabs')
model = sgio.read_output_model('cross_section.sg.K', 'vabs', model_type='BM2')

fig, ax = plt.subplots(figsize=(10, 8))
sgio.plot_sg_2d(cs, ax)      # geometry
sgio.plot_model_2d(model, ax)  # property overlay
ax.set_aspect('equal')
fig.savefig('cross_section.png', dpi=300)

sgio.plot_sg_2d_plotly() and sgio.plot_model_2d_plotly() are the interactive equivalents.

See Plot Cross-Section with Beam Properties.

Plot Multiple Cross-Sections Along a Span

Given a layout CSV of (location, section) pairs, sgio.plot_sg_3d_beam() and sgio.plot_sg_3d_beam_plotly() place every section at its spanwise station in one 3D view.

import sgio

sgio.plot_sg_3d_beam_plotly(
    csv_file='blade.csv',
    section_dir='cs',
    input_format='vabs',
    model_type='BM2',
    aspect_mode='data',
    output_html='blade_3d.html',
)

See Plot Blade Cross-Sections in 3D.

Plot Stiffness and Compliance Matrices

sgio.plot_matrix() renders a matrix as an annotated heatmap and sgio.plot_matrix_bar3d() as a 3D bar chart, which makes the coupling structure easier to read. Both take a raw matrix; symlog=True (the default) applies symmetric-log scaling so entries of very different magnitude stay legible.

import matplotlib.pyplot as plt
import sgio

model = sgio.read_output_model('cross_section.sg.K', 'vabs', model_type='BM1')

fig, ax = plt.subplots(figsize=(8, 6))
sgio.plot_matrix(model.stff, fig=fig, ax=ax, annotate=True, symlog=True)

sgio.plot_model_matrix() is the convenience wrapper: it takes the model object and selects the matrix by kind ('stiffness' or 'compliance'), labelling the rows and columns from the model’s theory schema.

sgio.plot_model_matrix(model, kind='stiffness')

Merge Sections into One Mesh

To inspect a whole blade in an external viewer, sgio.merge_sections_from_csv() translates each section to its spanwise station and writes a single merged mesh.

import sgio

sgio.merge_sections_from_csv(
    csv_file='blade.csv',
    section_dir='cs',
    input_format='vabs',
    output_file='blade_merged.msh',
    output_format='gmsh22',
)

See Merge Section Layout Data.

Bridge to PyVista and ParaView

sgio.SGMesh converts to and from PyVista, so any SG mesh — with its point_data and cell_data — can be rendered by VTK or written to ParaView’s native formats.

import sgio

sg = sgio.read('cross_section.sg', file_format='vabs', model_type='BM2')
grid = sg.mesh.to_pyvista()
grid.plot(scalars='property_id', show_edges=True, cpos='yz')

PyVista is optional and imported lazily; install it with pip install sgio[pyvista].

See Preview an SG Mesh with PyVista and View Blade Cross-Section Failure Results in ParaView.