Did you mean /infinite/? "Invinite" is not in any of the dictionaries I
queried, and it doesn't show on a google, except as a misspelling.
Yes, i meant "infinite" (sorry, was a typing error)
There could almost certainly be a way to provide a standard representation
of Pi. There may be a need for a PI_d, and a PI_f, but I don't see why
there is a fundamental reason it could not be part of the standard.
Perhaps I should take this over to comp.std.c++.
Someone wrote it before, some constants are defined in math.h (cmath).
/* Some useful constants. */
#if defined __USE_BSD || defined __USE_XOPEN
# define M_E 2.7182818284590452354 /* e */
# define M_LOG2E 1.4426950408889634074 /* log_2 e */
# define M_LOG10E 0.43429448190325182765 /* log_10 e */
# define M_LN2 0.69314718055994530942 /* log_e 2 */
# define M_LN10 2.30258509299404568402 /* log_e 10 */
# define M_PI 3.14159265358979323846 /* pi */
# define M_PI_2 1.57079632679489661923 /* pi/2 */
# define M_PI_4 0.78539816339744830962 /* pi/4 */
# define M_1_PI 0.31830988618379067154 /* 1/pi */
# define M_2_PI 0.63661977236758134308 /* 2/pi */
# define M_2_SQRTPI 1.12837916709551257390 /* 2/sqrt(pi) */
# define M_SQRT2 1.41421356237309504880 /* sqrt(2) */
# define M_SQRT1_2 0.70710678118654752440 /* 1/sqrt(2) */
#endif
/* The above constants are not adequate for computation using `long
double's.
Therefore we provide as an extension constants with similar names as a
GNU extension. Provide enough digits for the 128-bit IEEE quad. */
#ifdef __USE_GNU
# define M_El 2.7182818284590452353602874713526625L /* e */
# define M_LOG2El 1.4426950408889634073599246810018921L /* log_2 e */
# define M_LOG10El 0.4342944819032518276511289189166051L /* log_10
e */
# define M_LN2l 0.6931471805599453094172321214581766L /* log_e 2 */
# define M_LN10l 2.3025850929940456840179914546843642L /* log_e
10 */
# define M_PIl 3.1415926535897932384626433832795029L /* pi */
# define M_PI_2l 1.5707963267948966192313216916397514L /* pi/2 */
# define M_PI_4l 0.7853981633974483096156608458198757L /* pi/4 */
# define M_1_PIl 0.3183098861837906715377675267450287L /* 1/pi */
# define M_2_PIl 0.6366197723675813430755350534900574L /* 2/pi */
# define M_2_SQRTPIl 1.1283791670955125738961589031215452L /*
2/sqrt(pi) */
# define M_SQRT2l 1.4142135623730950488016887242096981L /* sqrt(2) */
# define M_SQRT1_2l 0.7071067811865475244008443621048490L /*
1/sqrt(2) */
#endif
Have a look at analysis 1.
I don't follow? Are you talking about "analysis" as in /real analysis/?
whats an irrational number .. thats what i wanted to say.
It makes no sense if you define Pi with ..... lets say 50 digits (in
this case: base 10) if you not define a datatype in this range for all
your variables.
simple example: 2*pi*r ...... what is the accuracy of pi (example long
double) worth, if r (example float) is only of low accuracy?
regards marbac