Universal numbers (data format)
Universal numbers, or unums, are a replacement for IEEE-754 floating-point numbers proposed by John Gustafson.
Posits are the most recent version of Gustafson's proposal. They have variable-sized index and mantissa bitfields, with the split being specified by a "regime" indicator. Gustafson claims that they offer better precision than standard floating-point numbers while taking up fewer bits.
Gustafson has published a book, The End of Error: Unum Computing, describing an earlier version of his system and its advantages. Posits are a more recent version of the same general scheme.
