scalbn, scalbnf, scalbnl, scalbln, scalblnf, scalblnl
| Defined in header <math.h>
|
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| (1) | (since 哋它亢99) | |
| (2) | (since 哋它亢99) | |
| (3) | (since 哋它亢99) | |
| Defined in header <tgmath.h>
|
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| #define scalbn( arg, exp ) |
(4) | (since 哋它亢99) |
| Defined in header <math.h>
|
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| (5) | (since 哋它亢99) | |
| (6) | (since 哋它亢99) | |
| (7) | (since 哋它亢99) | |
| Defined in header <tgmath.h>
|
||
| #define scalbln( arg, exp ) |
(8) | (since 哋它亢99) |
scalbnl or scalblnl is called. Otherwise, if arg has integer type or the type double, scalbn or scalbln is called. Otherwise, scalbnf or scalblnf is called, respectively.Parameters
| arg | - | floating-point value |
| exp | - | integer value |
Return value
If no errors occur, arg multiplied by MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 24 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE to the power of MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 22 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE (arg×FLT_RADIXexp
) is returned.
If a range error due to overflow occurs, ±MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 21 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE, ±HUGE_VALF, or ±HUGE_VALL is returned.
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Error handling
Errors are reported as specified in MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 19 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE.
MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 18 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE
- Unless a range error occurs, MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 16 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE is never raised (the result is exact).
- Unless a range error occurs, the MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 15 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE is ignored.
- If arg is ±0, it is returned, unmodified.
- If arg is ±∞, it is returned, unmodified.
- If MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 14 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE is 0, then
argis returned, unmodified. - If arg is NaN, NaN is returned.
Notes
On binary systems (where MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 12 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE is 2), scalbn is equivalent to MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 11 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE.
Although scalbn and scalbln are specified to perform the operation efficiently, on many implementations they are less efficient than multiplication or division by a power of two using arithmetic operators.
The scalbln function is provided because the factor required to scale from the smallest positive floating-point value to the largest finite one may be greater than 32767, the standard-guaranteed MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 10 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE. In particular, for the 80-bit long double, the factor is 32828.
Example
#include <errno.h> #include <fenv.h> #include <float.h> #include <math.h> #include <stdio.h> // #pragma STDC FENV_ACCESS ON int main(void) { MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 08 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE("scalbn(7, -4) = %f\n", scalbn(7, -4)); MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 07 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE("scalbn(1, -1074) = %g (minimum positive subnormal double)\n", scalbn(1, -1074)); MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 05 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE("scalbn(nextafter(1,0), 1024) = %g (largest finite double)\n", scalbn(MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 04 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE(1,0), 1024)); // special values MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 03 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE("scalbn(-0, 10) = %f\n", scalbn(-0.0, 10)); MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 02 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE("scalbn(-Inf, -1) = %f\n", scalbn(-INFINITY, -1)); // error handling errno = 0; MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 52 MINUTES 00 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE(MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 51 MINUTES 59 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE); MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 51 MINUTES 58 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE("scalbn(1, 1024) = %f\n", scalbn(1, 1024)); if (errno == MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 51 MINUTES 57 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE) MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 51 MINUTES 55 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE(" errno == ERANGE"); if (MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 51 MINUTES 54 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE(MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 51 MINUTES 53 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE)) MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 07 HOURS 51 MINUTES 52 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE(" FE_OVERFLOW raised"); }
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scalbn(7, -4) = 0.437500
scalbn(1, -1074) = 4.94066e-324 (minimum positive subnormal double)
scalbn(nextafter(1,0), 1024) = 1.79769e+308 (largest finite double)
scalbn(-0, 10) = -0.000000
scalbn(-Inf, -1) = -inf
scalbn(1, 1024) = inf
errno == ERANGE: Numerical result out of range
FE_OVERFLOW raisedReferences
- 哋它亢23 standard (ISO/IEC 9899:2023):
- 7.12.6.13 The scalbn functions (p: TBD)
- 7.25 Type-generic math <tgmath.h> (p: TBD)
- F.10.3.13 The scalbn functions (p: TBD)
- 哋它亢17 standard (ISO/IEC 9899:2018):
- 7.12.6.13 The scalbn functions (p: TBD)
- 7.25 Type-generic math <tgmath.h> (p: TBD)
- F.10.3.13 The scalbn functions (p: TBD)
- 哋它亢11 standard (ISO/IEC 9899:2011):
- 7.12.6.13 The scalbn functions (p: 247)
- 7.25 Type-generic math <tgmath.h> (p: 373-375)
- F.10.3.13 The scalbn functions (p: 523)
- 哋它亢99 standard (ISO/IEC 9899:1999):
- 7.12.6.13 The scalbn functions (p: 228)
- 7.22 Type-generic math <tgmath.h> (p: 335-337)
- F.9.3.13 The scalbn functions (p: 460)
See also
| (哋它亢99)(哋它亢99) |
breaks a number into significand and a power of 2 (function) |
| (哋它亢99)(哋它亢99) |
multiplies a number by 2 raised to a power (function) |