1SCALBLN(3) Linux Programmer's Manual SCALBLN(3)
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6 scalbn, scalbnf, scalbnl, scalbln, scalblnf, scalblnl - multiply float‐
7 ing-point number by integral power of radix
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10 #include <math.h>
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12 double scalbln(double x, long int exp);
13 float scalblnf(float x, long int exp);
14 long double scalblnl(long double x, long int exp);
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16 double scalbn(double x, int exp);
17 float scalbnf(float x, int exp);
18 long double scalbnl(long double x, int exp);
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20 Link with -lm.
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22 Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
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24 scalbln(), scalblnf(), scalblnl(): _XOPEN_SOURCE >= 600 ||
25 _ISOC99_SOURCE; or cc -std=c99
26 scalbn(), scalbnf(), scalbnl(): _BSD_SOURCE || _SVID_SOURCE ||
27 _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE; or cc -std=c99
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30 These functions multiply their first argument x by FLT_RADIX (probably
31 2) to the power of exp, that is:
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33 x * FLT_RADIX ** exp
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35 The definition of FLT_RADIX can be obtained by including <float.h>.
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38 On success, these functions return x * FLT_RADIX ** exp.
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40 If x is a NaN, a NaN is returned.
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42 If x is positive infinity (negative infinity), positive infinity (nega‐
43 tive infinity) is returned.
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45 If x is +0 (-0), +0 (-0) is returned.
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47 If the result overflows, a range error occurs, and the functions return
48 HUGE_VAL, HUGE_VALF, or HUGE_VALL, respectively, with a sign the same
49 as x.
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51 If the result underflows, a range error occurs, and the functions
52 return zero, with a sign the same as x.
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55 See math_error(7) for information on how to determine whether an error
56 has occurred when calling these functions.
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58 The following errors can occur:
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60 Range error, overflow
61 An overflow floating-point exception (FE_OVERFLOW) is raised.
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63 Range error, underflow
64 An underflow floating-point exception (FE_UNDERFLOW) is raised.
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66 These functions do not set errno.
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69 These functions first appeared in glibc in version 2.1.
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72 C99, POSIX.1-2001.
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75 These functions differ from the obsolete functions described in
76 scalb(3) in the type of their second argument. The functions described
77 on this page have a second argument of an integral type, while those in
78 scalb(3) have a second argument of type double.
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80 If FLT_RADIX equals 2 (which is usual), then scalbn() is equivalent to
81 ldexp(3).
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84 ldexp(3), scalb(3)
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87 This page is part of release 3.22 of the Linux man-pages project. A
88 description of the project, and information about reporting bugs, can
89 be found at http://www.kernel.org/doc/man-pages/.
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93 2008-08-11 SCALBLN(3)