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():
25 _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
26 || /* Since glibc 2.19: */ _DEFAULT_SOURCE
27 scalbn(), scalbnf(), scalbnl():
28 _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
29 || /* Since glibc 2.19: */ _DEFAULT_SOURCE
30 || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
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33 These functions multiply their first argument x by FLT_RADIX (probably
34 2) to the power of exp, that is:
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36 x * FLT_RADIX ** exp
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38 The definition of FLT_RADIX can be obtained by including <float.h>.
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41 On success, these functions return x * FLT_RADIX ** exp.
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43 If x is a NaN, a NaN is returned.
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45 If x is positive infinity (negative infinity), positive infinity (nega‐
46 tive infinity) is returned.
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48 If x is +0 (-0), +0 (-0) 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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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 Range error, overflow
64 An overflow floating-point exception (FE_OVERFLOW) is raised.
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66 Range error, underflow
67 An underflow floating-point exception (FE_UNDERFLOW) is raised.
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69 These functions do not set errno.
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72 These functions first appeared in glibc in version 2.1.
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75 For an explanation of the terms used in this section, see
76 attributes(7).
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78 ┌──────────────────────────────────┬───────────────┬─────────┐
79 │Interface │ Attribute │ Value │
80 ├──────────────────────────────────┼───────────────┼─────────┤
81 │scalbn(), scalbnf(), scalbnl(), │ Thread safety │ MT-Safe │
82 │scalbln(), scalblnf(), scalblnl() │ │ │
83 └──────────────────────────────────┴───────────────┴─────────┘
85 C99, POSIX.1-2001, POSIX.1-2008.
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88 These functions differ from the obsolete functions described in
89 scalb(3) in the type of their second argument. The functions described
90 on this page have a second argument of an integral type, while those in
91 scalb(3) have a second argument of type double.
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93 If FLT_RADIX equals 2 (which is usual), then scalbn() is equivalent to
94 ldexp(3).
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97 ldexp(3), scalb(3)
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100 This page is part of release 4.15 of the Linux man-pages project. A
101 description of the project, information about reporting bugs, and the
102 latest version of this page, can be found at
103 https://www.kernel.org/doc/man-pages/.
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107 2017-09-15 SCALBLN(3)