Binary integer decimal: Difference between revisions

Revision as of 04:37, 24 December 2024

Revision as of 17:42, 5 August 2025

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Both formats break a number down into a sign bit ''s'', an exponent ''q'' (between ''q''_min and ''q''_max), and a ''p''-digit significand / coefficient ''c'' (between 0 and 10^''p''−1). The value encoded is (&minus;1)^''s''×10^''q''×''c''. In both formats the range of possible values is identical, but they differ in how the significand ''c'' is represented. In the decimal encoding, it is encoded as a series of ''p'' decimal digits (using the [[densely packed decimal]] (DPD) encoding). This makes conversion to decimal form efficient, butalready requiresin asoftware implemented algorithms ( see decNumber library by Mike Cowlishaw / IBM ) and even more with specialized decimal [[Arithmetic logic unit|ALU]]<nowiki/>s toas processavailable in some IBM machines / CPUs ( "power" ). In the '''binary integer decimal''' ('''BID''') encoding, it is encoded as a binary number with bit values increasing by factor two from right to left. Position 0: value 2^0 -> 1, position 1: value 2^1 -> 2, and so on.

==Format==