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InfluxDB
Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.
I remember posting a similar list for introductory analysis (like the kind commonly required for math majors) too, but I didn't bother to figure out where that was, so I just looked up Volume I of the book by Jiří Lebl and found another good explanation of it, including cases where the function to be integrated is not continuous.
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