The .xdf format is a binary file format that:Â
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Stores data in blocks for efficient reading of arbitrary columns and contiguous rows
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Contains associated metadata, such as variable names, descriptions, and data storage types
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Supports a richer set of data storage types than R (eight types of integers, two types of floating point numbers
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Writes data blocks of rows so that data processing can be optimized
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Processes data in chunks (groups of blocks)
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Optimizes the block sizes depends on individual computer bandwidth for I/O
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Contains meta information at the end of the .xdf file rather than the beginning for easy updating