Uses HDF5, which itself is a great file format, well suited for big tables of numbers. Good for similar reasons as SQLite3, but for different applications. No

Uses HDF5, which itself is a great file format, well suited for big tables of numbers. Good for similar reasons as SQLite3, but for different applications. Not a relational database, columns are more strongly typed. Better suited when you have hundreds or thousands of columns, worse when you're trying to query a particular row.