Trend Ruby

Ruby client for Trend, the anomaly detection and forecasting API

Note: The hosted version is no longer available. See how to run the API on your own infrastructure.

Installation

Add this line to your application’s Gemfile:

gem "trend"

And set the URL to the API:

Trend.url = "http://localhost:8000"

Anomaly Detection

Detect anomalies in a time series

# generate series
series = {}
date = Date.parse("2026-01-01")
28.times do
  series[date] = rand(100)
  date += 1
end

# add an anomaly on Apr 21
series[date - 8] = 999

Trend.anomalies(series)

Works great with Groupdate

series = User.group_by_day(:created_at).count
Trend.anomalies(series)

Forecasting

Get future predictions for a time series

series = {}
date = Date.parse("2026-01-01")
28.times do
  series[date] = date.wday
  date += 1
end

Trend.forecast(series)

Also works great with Groupdate

series = User.group_by_day(:created_at).count
Trend.forecast(series)

Specify the number of predictions to return

Trend.forecast(series, count: 3)

Correlation (Experimental)

Get the correlation between two time series

Trend.correlation(series, series2)

History

View the changelog

Contributing

Everyone is encouraged to help improve this project. Here are a few ways you can help:

• Report bugs
• Fix bugs and submit pull requests
• Write, clarify, or fix documentation
• Suggest or add new features

To get started with development:

git clone https://github.com/ankane/trend-ruby.git
cd trend-ruby
bundle install
bundle exec rake test