TypeScript Ready • Easy to Use • All-in-One Cycle Engine

A TypeScript library for accurate menstrual cycle predictions, ovulation estimation, fertile windows, and cycle analytics.

---

🚺 vani-cycle

vani-cycle provides a flexible prediction engine for period tracking, ovulation calculations, and fertile window forecasting.
Built to be simple, private, and easy to integrate into any app.

---

✨ Features

• Predict the next menstrual period
• Estimate ovulation with cycle-based math
• Calculate fertile windows
• Strategy-based prediction (WMA + Calendar)
• Cycle irregularity detection
• Confidence scores + human-friendly notes
• Fully written in TypeScript

---

📦 Installation

npm install vani-cycle


# 🚺 **vani-cycle**

`vani-cycle` provides a flexible cycle prediction engine built for modern apps.  
It delivers clean predictions with confidence scores, windows, and human-friendly notes.

---

# ✨ Features

- Predict the next menstrual period  
- Estimate ovulation  
- Calculate fertile windows  
- Multiple strategies (WMA, Calendar)  
- Cycle irregularity detection  
- TypeScript support  
- Easy-to-use API  
- Zero external dependencies  

---

# 📦 Installation

```bash
npm install vani-cycle

---

🚀 Quick Start

import { PredictionEngine } from "vani-cycle";

const engine = new PredictionEngine({ strategy: "wma" });

const history = {
  periodStarts: [
    { date: "2025-01-02" },
    { date: "2025-01-30" },
    { date: "2025-02-27" }
  ]
};

const nextPeriod = engine.predictNextPeriod(history);
console.log("Next period:", nextPeriod);

const ovulation = engine.predictOvulation(history);
console.log("Ovulation:", ovulation);

const fertile = engine.predictFertileWindow(history);
console.log("Fertile Window:", fertile);

const analysis = engine.analyze(history);
console.log("Strategy Comparison:", analysis);

---

📊 Example Output

{
  "nextPeriod": {
    "likely": "2025-03-27",
    "confidence": 0.65,
    "notes": [
      "wma 27.50d",
      "pred interval 28d",
      "std 0.71d"
    ]
  },
  "ovulation": {
    "likely": "2025-03-13",
    "confidence": 0.65,
    "notes": [
      "estimated ovulation = 2025-03-13"
    ]
  }
}

---

📘 API Overview

PredictionEngine(config)

Methods

Method	Description
predictNextPeriod(history)	Predict next menstrual cycle
predictOvulation(history)	Estimate ovulation day
predictFertileWindow(history)	Calculate fertile range
predictPregnancy(lastPeriod)	Estimate due date and trimester
analyze(history)	Compare all prediction strategies

---

🧠 Strategies

WMA (Weighted Moving Average)

More accurate, gives priority to recent cycles.

Calendar

Simple average of all cycle lengths.

Custom Strategies

You can register your own:

engine.registerStrategy("myLogic", myStrategyFn);

---

🔍 Irregular Cycle Detection

Your library includes a built-in anomaly detector:

• detects unusual cycle jumps
• adjusts confidence
• returns human notes like: "Your cycles vary more than usual."

---

📄 License

MIT License.

---

❤️ Credits

Built by Narendra (nkrider) For real apps, real people, real health.