SimplexIQ

SimplexIQ is a React + Python (FastAPI) web app for solving Linear Programming problems using the Simplex (Big‑M) method, with step-by-step tableau iterations, sensitivity analysis (shadow prices/slack), templates, and visualizations.

Table of Contents

• Overview
• Key Features
• How It Works
• Tech Stack
• Project Structure
• Getting Started
• Usage Guide
• Available Scripts
• Configuration and Limits
• Quality and Testing
• Troubleshooting
• Security and Responsible Use
• Contributing
• License
• Disclaimer

Overview

SimplexIQ is designed for learners, analysts, and practitioners who want an interactive way to solve LP problems and understand the mechanics of simplex optimization.

The app supports:

• Objective function definition (maximize or minimize)
• Dynamic variable and constraint entry
• Constraint types (<=, >=, =)
• Iterative simplex tableau breakdown
• Result interpretation with shadow prices and binding constraints
• Visual analytics and graphical method support for 2-variable problems

Key Features

1. Interactive Problem Builder Configure variables, objective coefficients, and constraints in a structured UI.

2. Simplex Solver Engine Runs simplex logic and computes feasibility/optimality status.

3. Iteration Explorer Navigate pivot-by-pivot tableau states with entering/leaving variable indicators.

4. Sensitivity Analysis Review slack values, shadow prices, and binding constraints.

5. Visualization Dashboard Inspect solution distribution, capacity utilization, and dual-value trends.

6. Built-in Templates Load preconfigured LP scenarios for quick experimentation.

How It Works

1. Create or load a problem template.
2. Define objective type and coefficients.
3. Add constraints and right-hand-side values.
4. Run simplex solve.
5. Review results, iterations, and visualizations.

Tech Stack

• React 19
• Vite 8
• Recharts
• ESLint 9

Project Structure

frontend/
	src/                    React UI (unchanged)
	public/                 Static assets (favicon, etc.)

backend/
	app.py                  FastAPI app (exposes `/api/solve`)
	simplex_solver.py       Simplex/LPP solver implementation (Python)
	schemas.py              Request/response models

Getting Started

Prerequisites

• Node.js 18 or later
• npm 9 or later

Installation

cd frontend
npm install

cd ../backend
pip install -r requirements.txt

Run in Development

# Terminal 1 (project root):
python -m uvicorn backend.app:app --host 127.0.0.1 --port 8000

# Terminal 2:
cd frontend
npm run dev

Vite will print the local URL (for example: http://localhost:5173 or next available port). The UI calls http://localhost:8000/api/solve by default.

Build for Production

cd frontend
npm run build

Preview Production Build

cd frontend
npm run preview

Usage Guide

Input Section

• Choose objective type (maximize/minimize).
• Set variable and constraint counts.
• Enter objective coefficients and constraint rows.

Results Section

• View solution status and objective value.
• Inspect variable values and sensitivity table.

Iterations Section

• Track each simplex iteration.
• Identify entering and leaving variables.

Visualizations Section

• Compare variable values and resource usage.
• Analyze shadow prices in chart form.

Templates Section

• Load predefined LP scenarios to test quickly.

Available Scripts

• npm run dev - Start local development server
• npm run build - Generate production build
• npm run preview - Preview production bundle
• npm run lint - Run static lint checks

Configuration and Limits

Current UI safeguards include:

• Variable count range: 1 to 8
• Constraint count range: 1 to 10

These limits are configurable in input-handling logic if your use case requires higher ranges.

Quality and Testing

Minimum quality workflow:

npm run lint
npm run build

Recommended additions for production readiness:

• Unit tests for solver edge cases
• Integration tests for UI workflows
• Snapshot tests for key visualization states

Troubleshooting

1. Port already in use

• Vite automatically switches to another port.
• Open the URL shown in terminal output.

2. Build size warning

• The project may output a chunk size warning during build.
• Consider route-based code splitting if needed.

3. Dependency issues

• Remove node_modules and lockfile, then reinstall dependencies.

Security and Responsible Use

• Do not submit sensitive or confidential optimization data in shared deployments.
• Validate user-provided numeric inputs in any backend-integrated version.
• Apply authentication/authorization before exposing this app in multi-user environments.

Contributing

Contributions are welcome.

Recommended process:

1. Create a feature branch.
2. Keep changes focused and documented.
3. Run lint and build checks.
4. Submit a pull request with clear context and screenshots (if UI changes).

License

No license file is currently defined in this repository.

If you plan to distribute this project, add an explicit license file (for example MIT, Apache-2.0, or proprietary terms).

Disclaimer

SimplexIQ is provided for educational and analytical purposes. Results should be independently validated before use in business-critical or regulatory decision-making contexts.