Convert SG Data#

One of the main capabilities of SGIO is to convert SG data between different formats. This can be done using the sgio.convert() function (API) or the sgio convert command (CLI).

Overview#

SGIO supports conversion between:

  • VABS ↔ SwiftComp ↔ Abaqus ↔ Gmsh

  • Mesh-only conversions for visualization

  • Format version conversions (e.g., VABS 4.0 → 4.1)

Basic Usage#

API Method#

import sgio

sgio.convert(
    file_name_in='input.inp',
    file_name_out='output.sg',
    file_format_in='abaqus',
    file_format_out='vabs',
    model_type='BM2'
)

CLI Method#

sgio convert input.inp output.sg -ff abaqus -tf vabs -m BM2

Common Parameters#

  • file_name_in: Input file path

  • file_name_out: Output file path

  • file_format_in: Input format (vabs, swiftcomp, abaqus, gmsh)

  • file_format_out: Output format

  • model_type: Structural model (BM1, BM2, PL1, PL2, SD1)

  • mesh_only: Convert mesh data only (default: False)

  • renum_node: Renumber nodes (default: False)

  • renum_elem: Renumber elements (default: False)

Common Conversion Scenarios#

Scenario 1: VABS to Gmsh for Visualization#

Convert a VABS cross-section to Gmsh format for visualization.

API:

CLI:

sgio convert cs_box_t_vabs41.sg cs_box_t_vabs41.msh \
    -ff vabs -tf gmsh -m BM2 --mesh-only

Result:

Visualization of the box cross-section in Gmsh

Figure 1 Box cross-section visualized in Gmsh#

Scenario 2: Abaqus to VABS#

Convert an Abaqus cross-section model to VABS input format.

API:

import sgio

sgio.convert(
    'airfoil.inp',      # Abaqus input file
    'airfoil.sg',       # VABS output file
    'abaqus',           # Input format
    'vabs',             # Output format
    model_type='BM2'    # Timoshenko beam
)

CLI:

sgio convert airfoil.inp airfoil.sg -ff abaqus -tf vabs -m BM2

See examples/convert_abaqus_cs_to_vabs/ for a complete example.

Scenario 3: Abaqus to SwiftComp (3D)#

Convert a 3D Abaqus model to SwiftComp format.

API:

import sgio

sgio.convert(
    'cube.inp',         # Abaqus 3D model
    'cube.sg',          # SwiftComp output
    'abaqus',           # Input format
    'swiftcomp',        # Output format
    model_type='SD1',   # 3D solid model
    sgdim=3             # 3D structure gene
)

CLI:

sgio convert cube.inp cube.sg \
    -ff abaqus -tf swiftcomp -m SD1 --sgdim 3

See examples/convert_abaqus_sg3d_to_sc/ for a complete example.

Scenario 4: Format Version Conversion#

Convert between different versions of the same format.

VABS 4.0 to 4.1:

import sgio

sgio.convert(
    'old_format.sg',
    'new_format.sg',
    'vabs',
    'vabs',
    file_version_in='4.0',
    file_version_out='4.1',
    model_type='BM2'
)

Scenario 5: Two-Step Conversion#

For more control, use separate read and write operations:

import sgio

# Step 1: Read from Abaqus
sg = sgio.read('model.inp', 'abaqus', model_type='BM2')

# Inspect or modify the data
print(f"Nodes: {len(sg.mesh.points)}")
print(f"Elements: {len(sg.mesh.cells)}")

# Step 2: Write to VABS
sgio.write(sg, 'model.sg', 'vabs')

# Step 3: Also export for visualization
sgio.write(sg, 'model.msh', 'gmsh', mesh_only=True)

See Also#