Re: Machine epsilon: conclusion

Richard Heathfield wrote:
jacob navia said:

Richard Heathfield wrote:
jacob navia said:

<snip>
For the different representations we have in the standard header
<float.h>:

#define FLT_EPSILON 1.19209290e-07F // float
#define DBL_EPSILON 2.2204460492503131e-16 // double
#define LDBL_EPSILON 1.084202172485504434007452e-19L //long double
// qfloat epsilon truncated so that it fits in this page...
#define QFLT_EPSILON 1.09003771904865842969737513593110651 ... E-106
You have the same bug as last time. No standard-conforming
implementation may define QFLT_EPSILON in the standard header
<float.h>, as I pointed out to you earlier this week.

I have told you thousand times that this can be disabled
by using -ansic.

You don't seem to understand my point, which is that you are describing <float.h> as a *standard header*, and yet you *also* describe it as containing QFLT_EPSILON. It can't *both* be a standard header *and* contain QFLT_EPSILON at the same time. If it is a standard header, it does not contain QFLT_EPSILON. If it contains QFLT_EPSILON, it is not a standard header. Your claim that QFLT_EPSILON is in a standard header is simply wrong, switch or no switch.


The compiler you use has a file called
"math.h"

There, I can read

# 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) */

but that doesn't bother you since when you call that compiler
with the needed flags, those definitions do not appear.

When I do exactly the same you will argue without end.

The fact that my compiler is the only C compiler giving to the user
105 digits floating point precision is not important to you.

Polemic, polemic without end, but you did not contribute anything
to this discussion.


.

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