scalbl(3)

1SCALB(3)                   Linux Programmer's Manual                  SCALB(3)
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NAME

6       scalb,  scalbf,  scalbl  -  multiply  floating-point number by integral
7       power of radix (OBSOLETE)
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SYNOPSIS

10       #include <math.h>
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12       double scalb(double x, double exp);
13       float scalbf(float x, float exp);
14       long double scalbl(long double x, long double exp);
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16       Link with -lm.
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18   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
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20       scalb():
21           _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 500 ||
22           _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED
23       scalbf(), scalbl():
24           _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600
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DESCRIPTION

27       These  functions multiply their first argument x by FLT_RADIX (probably
28       2) to the power of exp, that is:
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30           x * FLT_RADIX ** exp
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32       The definition of FLT_RADIX can be obtained by including <float.h>.
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RETURN VALUE

35       On success, these functions return x * FLT_RADIX ** exp.
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37       If x or exp is a NaN, a NaN is returned.
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39       If x is positive infinity (negative infinity), and exp is not  negative
40       infinity, positive infinity (negative infinity) is returned.
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42       If x is +0 (-0), and exp is not positive infinity, +0 (-0) is returned.
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44       If  x is zero, and exp is positive infinity, a domain error occurs, and
45       a NaN is returned.
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47       If x is an infinity, and exp  is  negative  infinity,  a  domain  error
48       occurs, and a NaN is returned.
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50       If the result overflows, a range error occurs, and the functions return
51       HUGE_VAL, HUGE_VALF, or HUGE_VALL, respectively, with a sign  the  same
52       as x.
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54       If  the  result  underflows,  a  range  error occurs, and the functions
55       return zero, with a sign the same as x.
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ERRORS

58       See math_error(7) for information on how to determine whether an  error
59       has occurred when calling these functions.
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61       The following errors can occur:
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63       Domain  error:  x  is 0, and exp is positive infinity, or x is positive
64       infinity and exp is negative infinity and the other argument is  not  a
65       NaN
66              An invalid floating-point exception (FE_INVALID) is raised.
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68       Range error, overflow
69              An overflow floating-point exception (FE_OVERFLOW) is raised.
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71       Range error, underflow
72              An underflow floating-point exception (FE_UNDERFLOW) is raised.
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74       These functions do not set errno.
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CONFORMING TO

77       scalb()   is   specified   in  POSIX.1-2001,  but  marked  obsolescent.
78       POSIX.1-2008 removes the specification of scalb(), recommending the use
79       of  scalbln(3), scalblnf(3), or scalblnl(3) instead.  The scalb() func‐
80       tion is from 4.3BSD.
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82       scalbf() and scalbl()  are  unstandardized;  scalbf()  is  nevertheless
83       present on several other systems
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COLOPHON

89       This  page  is  part of release 3.53 of the Linux man-pages project.  A
90       description of the project, and information about reporting  bugs,  can
91       be found at http://www.kernel.org/doc/man-pages/.
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95                                  2013-03-23                          SCALB(3)