Generating Realistic Humidity Data for TimeScale DB with Data Diluvium

For next steps of why I set up TimeScale DB up for local dev, and being able to just do things, I need two new data generators over on Data Diluvium. One for humidity, which will be this post, and one for temperature, which will be next.

Why Humidity Data?

When working with TimeScale DB for time-series data, having realistic environmental data is crucial. I’ve found that humidity is a particularly important parameter that affects everything from agriculture to HVAC systems. Having realistic humidity data is essential for:

• Testing environmental monitoring systems
• Simulating weather conditions
• Developing IoT applications
• Training machine learning models for climate prediction

The Implementation

I created a humidity generator that produces realistic values based on typical Earth conditions. Here’s what I considered:

• Average humidity ranges (typically 30-70% for most inhabited areas)
• Daily variations (higher in the morning, lower in the afternoon)
• Seasonal patterns
• Geographic influences

With the definition of what needs to be generated, I created a table schema for Data Diluvium that would use this (and the temperature) data generators.

CREATE TABLE TestingHumidityAndTemperature (
    Identifier UUID PRIMARY KEY,
    StampInTime DATETIME,
    Temperature DOUBLE,
    Humidity DOUBLE
);

Since both Temperature and Humidity generators will be double values, to test humidity while we implement, I’ll just set temperature to humidity too.

The Data Diluvium App Code

Here’s how I implemented this in Data Diluvium:

export const humidityGenerator: GeneratorConfig = {
  name: 'Humidity',
  description: 'Generates realistic humidity values with daily and seasonal variations',
  category: 'number',
  compatibleTypes: [
    'NUMBER', 'DECIMAL', 'NUMERIC', 'FLOAT', 'DOUBLE',
    'NUMBER(5,2)', 'DECIMAL(5,2)', 'NUMERIC(5,2)'
  ],
  defaultOptions: {
    minHumidity: 30,
    maxHumidity: 70,
    includeTimeVariation: true,
    includeSeasonalVariation: true
  },
  generate: async (count: number, options?: GeneratorOptions) => {
    const finalOptions = { ...humidityGenerator.defaultOptions, ...options };
    
    return Array.from({ length: count }, () => {
      let baseHumidity = finalOptions.minHumidity! + 
        (Math.random() * (finalOptions.maxHumidity! - finalOptions.minHumidity!));

      if (finalOptions.includeTimeVariation) {
        // Add daily variation (higher in morning, lower in afternoon)
        const hour = new Date().getHours();
        const timeFactor = Math.sin((hour - 6) * Math.PI / 12); // Peak at 6 AM
        baseHumidity += timeFactor * 10;
      }

      if (finalOptions.includeSeasonalVariation) {
        // Add seasonal variation (higher in winter, lower in summer)
        const month = new Date().getMonth();
        const seasonalFactor = Math.sin((month - 1) * Math.PI / 6); // Peak in January
        baseHumidity += seasonalFactor * 5;
      }

      // Ensure the value stays within bounds
      return Math.max(finalOptions.minHumidity!, Math.min(finalOptions.maxHumidity!, baseHumidity));
    });
  }
};

Using the Generator with TimeScale DB

{
  "generator": "humidity",
  "options": {
    "minHumidity": 25,
    "maxHumidity": 75,
    "includeTimeVariation": true,
    "includeSeasonalVariation": true
  }
}

This configuration works perfectly with TimeScale DB’s time-series capabilities, allowing you to generate continuous humidity data that follows natural patterns over time.

describe('Humidity Generator', () => {
  it('should generate values within specified range', () => {
    const value = generateHumidity({
      minHumidity: 40,
      maxHumidity: 60
    });
    expect(value).toBeGreaterThanOrEqual(40);
    expect(value).toBeLessThanOrEqual(60);
  });

  it('should respect time-based variations', () => {
    const morningValue = generateHumidity({ includeTimeVariation: true });
    const afternoonValue = generateHumidity({ includeTimeVariation: true });
    expect(morningValue).toBeGreaterThan(afternoonValue);
  });
});

Alright, next up I’m going to test this and see what I get. Clicking over to the generate data tab it looks like the data is generating as expected and what is being generated will work for what I need.

Clicking through again to generate data, the humidity settings look mostly ok. I think I’ll come back to this after a while, and maybe change some parameters. But for now, this is good for what I’ll need for further testing and development.

Next up I’ll add the temperature generator, tweak them until they’re effective, and will get a feature addition up at https://datadiluvium.com and you too can give em’ a try!

With that, until next time happy thrashing coding! 🚀