Supported C99 Functions

namespace boost{ namespace math{ namespace tr1{ extern "C"{

typedef unspecified float_t;
typedef unspecified double_t;

double acosh(double x);
float acoshf(float x);
long double acoshl(long double x);

double asinh(double x);
float asinhf(float x);
long double asinhl(long double x);

double atanh(double x);
float atanhf(float x);
long double atanhl(long double x);

double cbrt(double x);
float cbrtf(float x);
long double cbrtl(long double x);

double copysign(double x, double y);
float copysignf(float x, float y);
long double copysignl(long double x, long double y);

double erf(double x);
float erff(float x);
long double erfl(long double x);

double erfc(double x);
float erfcf(float x);
long double erfcl(long double x);

double expm1(double x);
float expm1f(float x);
long double expm1l(long double x);

double fmax(double x, double y);
float fmaxf(float x, float y);
long double fmaxl(long double x, long double y);

double fmin(double x, double y);
float fminf(float x, float y);
long double fminl(long double x, long double y);

double hypot(double x, double y);
float hypotf(float x, float y);
long double hypotl(long double x, long double y);

double lgamma(double x);
float lgammaf(float x);
long double lgammal(long double x);

long long llround(double x);
long long llroundf(float x);
long long llroundl(long double x);

double log1p(double x);
float log1pf(float x);
long double log1pl(long double x);

long lround(double x);
long lroundf(float x);
long lroundl(long double x);

double nextafter(double x, double y);
float nextafterf(float x, float y);
long double nextafterl(long double x, long double y);

double nexttoward(double x, long double y);
float nexttowardf(float x, long double y);
long double nexttowardl(long double x, long double y);

double round(double x);
float roundf(float x);
long double roundl(long double x);

double tgamma(double x);
float tgammaf(float x);
long double tgammal(long double x);

double trunc(double x);
float truncf(float x);
long double truncl(long double x);

}}}} // namespaces

In addition sufficient additional overloads of the double versions of the above functions are provided, so that calling the function with any mixture of float, double, long double, or integer arguments is supported, with the return type determined by the result type calculation rules.

For example:

acoshf(2.0f);  // float version, returns float.
acosh(2.0f);   // also calls the float version and returns float.
acosh(2.0);    // double version, returns double.
acoshl(2.0L);  // long double version, returns a long double.
acosh(2.0L);   // also calls the long double version.
acosh(2);      // integer argument is treated as a double, returns double.

Quick Reference

More detailed descriptions of these functions are available in the C99 standard.

typedef unspecified float_t;
typedef unspecified double_t;

In this implementation float_t is the same as type float, and double_t the same as type double unless the preprocessor symbol FLT_EVAL_METHOD is defined, in which case these are set as follows:

double acosh(double x);
float acoshf(float x);
long double acoshl(long double x);

Returns the inverse hyperbolic cosine of x.

See also acosh for the full template (header only) version of this function.

double asinh(double x);
float asinhf(float x);
long double asinhl(long double x);

Returns the inverse hyperbolic sine of x.

See also asinh for the full template (header only) version of this function.

double atanh(double x);
float atanhf(float x);
long double atanhl(long double x);

Returns the inverse hyperbolic tangent of x.

See also atanh for the full template (header only) version of this function.

double cbrt(double x);
float cbrtf(float x);
long double cbrtl(long double x);

Returns the cubed root of x.

See also cbrt for the full template (header only) version of this function.

double copysign(double x, double y);
float copysignf(float x, float y);
long double copysignl(long double x, long double y);

Returns a value with the magnitude of x and the sign of y.

double erf(double x);
float erff(float x);
long double erfl(long double x);

Returns the error function of x:

See also erf for the full template (header only) version of this function.

double erfc(double x);
float erfcf(float x);
long double erfcl(long double x);

Returns the complementary error function of x 1-erf(x) without the loss of precision implied by the subtraction.

See also erfc for the full template (header only) version of this function.

double expm1(double x);
float expm1f(float x);
long double expm1l(long double x);

Returns exp(x)-1 without the loss of precision implied by the subtraction.

See also expm1 for the full template (header only) version of this function.

double fmax(double x, double y);
float fmaxf(float x, float y);
long double fmaxl(long double x, long double y);

Returns the larger (most positive) of x and y.

double fmin(double x, double y);
float fminf(float x, float y);
long double fminl(long double x, long double y);

Returns the smaller (most negative) of x and y.

double hypot(double x, double y);
float hypotf(float x, float y);
long double hypotl(long double x, long double y);

Returns sqrt(x*x + y*y) without the danger of numeric overflow implied by that formulation.

See also hypot for the full template (header only) version of this function.

double lgamma(double x);
float lgammaf(float x);
long double lgammal(long double x);

Returns the log of the gamma function of x.

See also lgamma for the full template (header only) version of this function.

long long llround(double x);
long long llroundf(float x);
long long llroundl(long double x);

Returns the value x rounded to the nearest integer as a long long: equivalent to floor(x + 0.5)

See also round for the full template (header only) version of this function.

double log1p(double x);
float log1pf(float x);
long double log1pl(long double x);

Returns the log(x+1) without the loss of precision implied by that formulation.

See also log1p for the full template (header only) version of this function.

long lround(double x);
long lroundf(float x);
long lroundl(long double x);

Returns the value x rounded to the nearest integer as a long: equivalent to floor(x + 0.5)

See also round for the full template (header only) version of this function.

double nextafter(double x, double y);
float nextafterf(float x, float y);
long double nextafterl(long double x, long double y);

Returns the next representable floating point number after x in the direction of y, or x if x == y.

double nexttoward(double x, long double y);
float nexttowardf(float x, long double y);
long double nexttowardl(long double x, long double y);

As nextafter, but with y always expressed as a long double.

double round(double x);
float roundf(float x);
long double roundl(long double x);

Returns the value x rounded to the nearest integer: equivalent to floor(x + 0.5)

See also round for the full template (header only) version of this function.

double tgamma(double x);
float tgammaf(float x);
long double tgammal(long double x);

Returns the gamma function of x:

See also tgamma for the full template (header only) version of this function.

double trunc(double x);
float truncf(float x);
long double truncl(long double x);

Returns x truncated to the nearest integer.

See also trunc for the full template (header only) version of this function.

See also C99 ISO Standard