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A logarithmic number system (LNS) is an arithmetic system for representing real numbers. In LNS, a number X, is represented by the logarithm L of its absolute value:

   X -> { s, L = \log_b(|X|) }

where s denotes the sign of X (s = 1 if X > 0 and s = -1 if X < 0).



Library procedures

[procedure] lognum?:: X -> BOOL
[procedure] lognum-sign:: X -> INTEGER
[procedure] lognum-value:: X -> NUMBER
[procedure] number->lognum:: NUMBER -> LOGNUM
[procedure] lognum->number:: LOGNUM -> NUMBER
[procedure] lognum+:: A * B -> X
[procedure] lognum-:: A * B -> X
[procedure] lognum*:: A * B -> X
[procedure] lognum/:: A * B -> X
[procedure] lognum-neg:: A -> B
[procedure] lognum-abs:: A -> B
[procedure] lognum-signum:: A -> B
[procedure] lognum-recip:: A -> B


Ivan Raikov


Ported to Chicken 4
Initial version


Copyright 2009 Ivan Raikov and the Okinawa Institute of Science and Technology.

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