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FloorLog2, FloorLog10, FloorLogBase

integer part of the logarithm
FloorLog2(X: RAT): INT
FloorLog10(X: RAT): INT
FloorLogBase(X: RAT, base: INT): INT 
These functions compute the integer part (floor) of the logarithm of a
rational number in a given base.
FloorLog2(X)
is just shorthand
for
FloorLogBase(X,2)
; similarly for
FloorLog10
.
NOTE: The signs of
X
and
base
are ignored.
These functions were called
ILogBase
up to version CoCoA5.1.2.
/**/ FloorLog2(128);
7
/**/ FloorLog10(999);
2
/**/ FloorLogBase(128,2);
7
/**/ FloorLogBase(81.5,3);
4
