Y = log2(X)
[F,E] = log2(X)
log2(X)
computes the base 2 logarithm of the elements of X
.
[F,E] = log2(X)
for a real matrix X
, returns a matrix F
of real numbers, usually in the range 0.5 <= abs(F) < 1
, and a matrix E
of integers, so that X = F.
* 2.^E
. Any zeros in X
produce F = 0
and E = 0
.
This function corresponds to the ANSI C function frexp()
and the IEEE floating-point standard function logb()
.
[F,E] = log2(X)
yields the following values.
X F E
1 1/2 1
pi pi/4 2
-3 -3/4 2
eps 1/2 -51
realmax 1-eps/2 1024
realmin 1/2 -1021
format
hex
,log
,pow2
,realmax
,realmin
(c) Copyright 1994 by The MathWorks, Inc.