# XLSX To Python Test Assertion Patterns By Data Type

> Sub-skill of xlsx-to-python: Test Assertion Patterns by Data Type (+1).

- Skill: `vamseeachanta/xlsx-to-python-test-assertion-patterns-by-data-type` (Agent Skill)
- Install (CLI): `npx skillmds@latest add vamseeachanta/xlsx-to-python-test-assertion-patterns-by-data-type`
- Raw SKILL.md: https://api.skillmd.com/api/skills/vamseeachanta/xlsx-to-python-test-assertion-patterns-by-data-type/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Data & Analytics
- Author: vamseeachanta (https://skillmd.com/u/vamseeachanta)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/vamseeachanta/xlsx-to-python-test-assertion-patterns-by-data-type

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# Test Assertion Patterns by Data Type (+1)

## Test Assertion Patterns by Data Type


| Excel Cell Type | Python Test Pattern |
|----------------|-------------------|
| Number (float) | `assert result == pytest.approx(expected, rel=1e-6)` |
| Integer | `assert result == expected` |
| Boolean | `assert result is True/False` |
| String | `assert result == "expected_string"` |
| Date | `assert result == datetime(YYYY, M, D)` |
| Error (#REF!, #N/A) | Skip — log as extraction gap |


## Tolerance Selection


| Domain | Typical Tolerance | Rationale |
|--------|------------------|-----------|
| Structural (stress, force) | `rel=1e-4` | 4 sig figs standard in engineering |
| Geotechnical (soil params) | `rel=1e-3` | Higher uncertainty in soil data |
| Financial (currency) | `abs=0.01` | Cent-level precision |
| General engineering | `rel=1e-6` | Default — tighten if needed |