@comment better formatting.
@comment
@menu
+* Typedef and constants:: Defined data types and constants
* Math Library Routines:: The Libquadmath math runtime application
programming interface.
* I/O Library Routines:: The Libquadmath I/O runtime application
@c ---------------------------------------------------------------------
+@c Defined macros
+@c ---------------------------------------------------------------------
+
+@node Typedef and constants
+@chapter Typedef and constants
+
+The following data type has been defined via @code{typedef}.
+
+@table @asis
+@item @code{__complex128}: @code{__float128}-based complex number
+@end table
+
+The following macros are defined, which give the numeric limits of the
+@code{__float128} data type.
+
+@table @asis
+@item @code{FLT128_MAX}: largest finite number
+@item @code{FLT128_MIN}: smallest positive number with full precision
+@item @code{FLT128_EPSILON}: difference between 1 and the next larger
+ representable number
+@item @code{FLT128_DENORM_MIN}: smallest positive denormalized number
+@item @code{FLT128_MANT_DIG}: number of digits in the mantissa (bit precision)
+@item @code{FLT128_MIN_EXP}: maximal negative exponent
+@item @code{FLT128_MAX_EXP}: maximal positive exponent
+@end table
+
+The following mathematical constants of type @code{__float128} are defined.
+
+@table @asis
+@item @code{M_Eq}: the constant e (Euler's number)
+@item @code{M_LOG2Eq}: binary logarithm of 2
+@item @code{M_LOG10Eq}: common, decimal logarithm of 2
+@item @code{M_LN2q}: natural logarithm of 2
+@item @code{M_LN10q}: natural logarithm of 10
+@item @code{M_PIq}: pi
+@item @code{M_PI_2q}: two pi
+@item @code{M_PI_4q}: four pi
+@item @code{M_1_PIq}: one over pi
+@item @code{M_2_PIq}: one over two pi
+@item @code{M_2_SQRTPIq}: two over square root of pi
+@item @code{M_SQRT2q}: square root of 2
+@item @code{M_SQRT1_2q}: one over square root of 2
+@end table
+
+
+@c ---------------------------------------------------------------------
@c Math routines
@c ---------------------------------------------------------------------
@item @code{expm1q}: exponential minus 1 function
@need 800
@item @code{fabsq}: absolute value function
+@item @code{fdimq}: positive difference function
@item @code{finiteq}: check finiteness of value
@item @code{floorq}: floor value function
@item @code{fmaq}: fused multiply and add
+@item @code{fmaxq}: determine maximum of two values
+@item @code{fminq}: determine minimum of two values
@item @code{fmodq}: remainder value function
@item @code{frexpq}: extract mantissa and exponent
@item @code{hypotq}: Eucledian distance function
+@item @code{ilogbq}: get exponent of the value
@item @code{isinfq}: check for infinity
@item @code{isnanq}: check for not a number
@item @code{j0q}: Bessel function of the first kind, first order
@item @code{jnq}: Bessel function of the first kind, @var{n}-th order
@item @code{ldexpq}: load exponent of the value
@item @code{lgammaq}: logarithmic gamma function
+@item @code{llrintq}: round to nearest integer value
@item @code{llroundq}: round to nearest integer value away from zero
@item @code{logq}: natural logarithm function
@item @code{log10q}: base 10 logarithm function
@item @code{log1pq}: compute natural logarithm of the value plus one
+@item @code{log2q}: base 2 logarithm function
@need 800
+@item @code{lrintq}: round to nearest integer value
@item @code{lroundq}: round to nearest integer value away from zero
@item @code{modfq}: decompose the floating-point number
@item @code{nanq}: return quiet NaN
+@item @code{nearbyintq}: round to nearest integer
@item @code{nextafterq}: next representable floating-point number
@item @code{powq}: power function
@item @code{remainderq}: remainder function
+@item @code{remquoq}: remainder and part of quotient
@item @code{rintq}: round-to-nearest integral value
@item @code{roundq}: round-to-nearest integral value, return @code{__float128}
@item @code{scalblnq}: compute exponent using @code{FLT_RADIX}
@item @code{y0q}: Bessel function of the second kind, first order
@item @code{y1q}: Bessel function of the second kind, second order
@item @code{ynq}: Bessel function of the second kind, @var{n}-th order
-@item @code{cabsq} complex absolute value function:
+@item @code{cabsq} complex absolute value function
@item @code{cargq}: calculate the argument
+@item @code{cimagq} imaginary part of complex number
+@item @code{crealq}: real part of complex number
+@item @code{cacoshq}: complex arc hyperbolic cosine function
+@item @code{cacosq}: complex arc cosine function
+@item @code{casinhq}: complex arc hyperbolic sine function
+@item @code{casinq}: complex arc sine function
+@item @code{catanhq}: complex arc hyperbolic tangent function
+@item @code{catanq}: complex arc tangent function
@item @code{ccosq} complex cosine function:
@item @code{ccoshq}: complex hyperbolic cosine function
@item @code{cexpq}: complex exponential function
+@need 800
@item @code{cexpiq}: computes the exponential function of ``i'' times a
real value
@item @code{clogq}: complex natural logarithm
@item @code{clog10q}: complex base 10 logarithm
+@item @code{conjq}: complex conjugate function
@item @code{cpowq}: complex power function
+@item @code{cprojq}: project into Riemann Sphere
@item @code{csinq}: complex sine function
@item @code{csinhq}: complex hyperbolic sine function
-@need 800
@item @code{csqrtq}: complex square root
@item @code{ctanq}: complex tangent function
@item @code{ctanhq}: complex hyperbolic tangent function
@chapter I/O Library Routines
@menu
-* @code{quadmath_strtopQ}: quadmath_strtopQ, Convert from string
-* @code{quadmath_dtoaq}: quadmath_dtoaq, Convert to string
+* @code{strtoflt128}: strtoflt128, Convert from string
+* @code{quadmath_snprintf}: quadmath_snprintf, Convert to string
@end menu
-@node quadmath_strtopQ
-@section @code{quadmath_strtopQ} --- Convert from string
+@node strtoflt128
+@section @code{strtoflt128} --- Convert from string
The function @code{dmath_strtopQ} converts a string into a
@code{__float128} number.
@table @asis
@item Syntax
-@code{int quadmath_strtopQ (const char *s, char **sp, void *V)}
+@code{__float128 strtoflt128 (const char *s, char **sp)}
@c The return values are defined in gdtoa/gdtoa.h STRTOG_*
@c However, the values are currently not exported - thus we
@multitable @columnfractions .15 .70
@item @var{s} @tab input string
@item @var{sp} @tab the address of the next character in the string
-@item @var{V} @tab @code{__float128} containing the converted number
@end multitable
The argument @var{sp} contains, if not @code{NULL}, the address of the
int main ()
@{
__float128 r;
- char str[200];
- quadmath_strtopQ ("1.2345678", NULL, &r);
+ r = strtoflt128 ("1.2345678", NULL);
return 0;
@}
@end table
-@node quadmath_dtoaq
-@section @code{quadmath_dtoaq} --- Convert to string
+@node quadmath_snprintf
+@section @code{quadmath_snprintf} --- Convert to string
-The function @code{quadmath_dtoaq} converts a @code{__float128} floating-point
-number into a string.
+The function @code{quadmath_snprintf} converts a @code{__float128} floating-point
+number into a string. It is a specialized alternative to @code{snprintf}, where
+the format string is restricted to a single conversion specifier with @code{Q}
+modifier and conversion specifier @code{e}, @code{E}, @code{f}, @code{F}, @code{g},
+@code{G}, @code{a} or @code{A}, with no extra characters before or after the
+conversion specifier. The @code{%m$} or @code{*m$} style must not be used in
+the format.
@table @asis
@item Syntax
-@code{void quadmath_dtoaq (char *s, size_t size, size_t n, __float128 x)}
+@code{int quadmath_snprintf (char *s, size_t size, const char *format, ...)}
@item @emph{Arguments}:
@multitable @columnfractions .15 .70
@item @var{s} @tab output string
@item @var{size} @tab byte size of the string, including tailing NUL
-@item @var{n} @tab number of digits after the decimal point
-@item @var{x} @tab the number to be converted
+@item @var{format} @tab conversion specifier string
@end multitable
@item Example
@smallexample
#include <quadmath.h>
+#include <stdlib.h>
+#include <stdio.h>
int main ()
@{
__float128 r;
- char str[200];
+ int prec = 20;
+ int width = 46;
+ char buf[128];
r = 2.0q;
- r = sqrtq(r);
- quadmath_dtoaq (str, sizeof (str), 20, r);
- printf("%s\n", str);
- /* Prints: +1.41421356237309504880e+00 */
+ r = sqrtq (r);
+ int n = quadmath_snprintf (buf, sizeof buf, "%+-#*.20Qe", width, r);
+ if ((size_t) n < sizeof buf)
+ printf ("%s\n", buf);
+ /* Prints: +1.41421356237309504880e+00 */
+ quadmath_snprintf (buf, sizeof buf, "%Qa", r);
+ if ((size_t) n < sizeof buf)
+ printf ("%s\n", buf);
+ /* Prints: 0x1.6a09e667f3bcc908b2fb1366ea96p+0 */
+ n = quadmath_snprintf (NULL, 0, "%+-#46.*Qe", prec, r);
+ if (n > -1)
+ @{
+ char *str = malloc (n + 1);
+ if (str)
+ @{
+ quadmath_snprintf (str, n + 1, "%+-#46.*Qe", prec, r);
+ printf ("%s\n", str);
+ /* Prints: +1.41421356237309504880e+00 */
+ @}
+ free (str);
+ @}
return 0;
@}
@end smallexample
+
@end table
+On some targets when supported by the C library hooks are installed
+for @code{printf} family of functions, so that @code{printf ("%Qe", 1.2Q);}
+etc.@: works too.
+
@c ---------------------------------------------------------------------
@c GNU Free Documentation License