| name | calculix-sim |
| description | Use when driving CalculiX (CCX) via Abaqus-style .inp input decks — open-source static/frequency/thermal FEA through sim runtime one-shot execution. |
calculix-sim
You are connected to CalculiX (CCX) via sim-cli. This file is the
index. It tells you where to look for actual content — it does not
contain the content itself.
CalculiX is an open-source finite element solver by Guido Dhondt. It
reads Abaqus-dialect .inp input decks and writes results to .frd
(field) and .dat (text tables via *NODE PRINT / *EL PRINT).
Execution is pure subprocess: ccx <jobname> (no .inp extension).
base/ — always relevant
| Path | What's there |
|---|
base/reference/inp_keywords.md | CalculiX-supported *KEYWORD list — what works, what's Abaqus-only. |
base/reference/analysis_types.md | Static / Frequency / Thermal / Coupled procedures. |
base/reference/result_files.md | .frd and .dat format; how to extract numeric results. |
base/snippets/01_cantilever_beam.inp | Verified cantilever beam E2E snippet (B32R beams). |
base/known_issues.md | Quirks discovered during TDD (LD_LIBRARY_PATH, glibc compat). |
solver/2.11/ — CalculiX 2.11 specifics
solver/2.11/notes.md — Debian buster build, spooles dep, glibc limits.
Hard constraints
ccx takes the jobname without extension. ccx beam, NOT ccx beam.inp.
- Not all Abaqus keywords are supported. Before inventing a keyword,
check
base/reference/inp_keywords.md — if it's not listed, don't use it.
- Acceptance != exit code. Validate against physics (displacement,
stress, frequency ranges), not just "Job finished".
- Output requires explicit keywords. Without
*NODE FILE / *EL FILE
the .frd is empty; without *NODE PRINT / *EL PRINT the .dat is empty.
- LD_LIBRARY_PATH may be required — the driver sets this automatically
when the deb-package layout is detected.
Required protocol
After sim check calculix confirms availability: gather Category A
inputs from user (geometry, materials, BCs, loads, analysis type,
acceptance criteria). Write the .inp deck using only CalculiX-supported
keywords. Lint with sim lint. Run with sim run --solver calculix.
Parse .dat (preferred for numeric extraction) or .frd for results.
Validate against physics-based acceptance.