IBM hexadecimal floating-point

Hexadecimal floating point (now called HFP by IBM) is a format for encoding floating-point numbers first introduced on the IBM System/360 computers, and supported on subsequent machines based on that architecture, as well as machines which were intended to be application-compatible with System/360. In comparison to IEEE 754 floating point, the HFP format has a longer significand, and a shorter exponent.

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