std::expm1

 

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abs(int)labsllabsimaxabs (C++11) abs(float)fabs divldivlldivimaxdiv (C++11) fmod	remainder (C++11) remquo (C++11) fma (C++11) fmax (C++11) fmin (C++11) fdim (C++11) nannanfnanl (C++11)(C++11)(C++11)
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fpclassify (C++11) isfinite (C++11) isinf (C++11) isnan (C++11) isnormal (C++11) signbit (C++11)	isgreater (C++11) isgreaterequal (C++11) isless (C++11) islessequal (C++11) islessgreater (C++11) isunordered (C++11)
Macro constants
HUGE_VALFHUGE_VALHUGE_VALL (C++11)(C++11) INFINITY (C++11) NAN (C++11) math_errhandlingMATH_ERRNOMATH_ERREXCEPT (C++11)	FP_NORMALFP_SUBNORMALFP_ZEROFP_INFINITEFP_NAN (C++11)(C++11)(C++11)(C++11)(C++11)

 

Defined in header <cmath>
float       expm1( float arg );		(since C++11)
double      expm1( double arg );		(since C++11)
long double expm1( long double arg );		(since C++11)
double      expm1( Integral arg );		(since C++11)

Computes the e (Euler's number, 2.7182818) raised to the given power arg, minus 1. This function is more accurate than the expression std::exp(arg)-1 if arg is close to zero.

Parameters

arg

-

value of floating-point or Integral type

Return value

earg
-1

If the result is too large for the underlying type, range error occurs and HUGE_VAL is returned.

See also

exp	returns e raised to the given power (ex) (function)
log1p (C++11)	natural logarithm (to base e) of 1 plus the given number (function)
exp2 (C++11)	returns 2 raised to the given power (2x) (function)
C documentation for expm1