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/*
* (C) Copyright 2005- ECMWF.
*
* This software is licensed under the terms of the Apache Licence Version 2.0
* which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
*
* In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
* virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
*/
#include <stdio.h>
#include <float.h>
#include "grib_api_internal.h"
double min = -1.0000000001;
double max = -1.00000000001;
double scale;
typedef unsigned long (*ieee_to_long_proc)(double);
typedef double (*long_to_ieee_proc)(unsigned long);
#if 0
static void test(unsigned long input, ieee_to_long_proc ieee_to_long, long_to_ieee_proc long_to_ieee)
{
double x1 = long_to_ieee(input);
unsigned long num2 = ieee_to_long(x1);
printf("\nconv input=%ld to double=%.10f (%g) and back => %ld\n", input, x1, x1, num2);
if (num2!=input) printf("ERROR: input=%ld not equal!!!\n", input);
}
double p(double ref1,double ref2)
{
double scale = (max-ref1) / 65535;
unsigned long pack = (unsigned long)(((max - ref1)/scale)+0.5);
double unpack = pack*scale + ref2;
printf(" max: %04X %0.20f %0.20f\n",pack,unpack,max-unpack);
pack = (unsigned long)(((min- ref1)/scale)+0.5);
unpack = pack*scale + ref2;
printf(" min: %04X %0.20f %0.20f\n",pack,unpack,min-unpack);
printf("\n");
return unpack;
}
#endif
/* generate a random floating point number from min to max */
static double randfrom(double minimum, double maximum)
{
double range = (maximum - minimum);
double div = RAND_MAX / range;
return minimum + (rand() / div);
}
/* Return 1 on success, 0 on failure */
static int test_doubles(ieee_to_long_proc ieee_to_long, long_to_ieee_proc long_to_ieee)
{
const double tolerance = 1e-7;
const double increment = 1;
const double max_value = 10 * 1000 * 1000;
const double min_value = -max_value;
double d = max_value;
int num_errors = 0;
int num_trials = 0;
double max_reldiff = -DBL_MAX;
while (d > min_value) {
double start = randfrom(0.7, 1) * d;
unsigned long a = ieee_to_long(start);
double end = long_to_ieee(a);
num_trials++;
if (start != 0.0) {
double reldiff = fabs(end - start) / start;
if (reldiff > tolerance) {
printf("Error: %.10f (diff=%.10f)\n", start, reldiff);
num_errors++;
}
else {
/*printf("Success: %.10f (diff=%.10f)\n", start, reldiff);*/
}
if (reldiff > max_reldiff) max_reldiff = reldiff;
}
d -= increment;
}
printf("trials = %d, errors = %d\n", num_trials, num_errors);
printf("max reldiff = %g\n", max_reldiff);
return num_errors == 0 ? 1 : 0;
}
int main(int argc, char* argv[])
{
#if 1
unsigned long i = 0;
printf("Test doubles with grib_ieee_to_long/grib_long_to_ieee...\n");
ECCODES_ASSERT(test_doubles(grib_ieee_to_long, grib_long_to_ieee) == 1);
printf("Test doubles with grib_ieee64_to_long/grib_long_to_ieee64...\n");
ECCODES_ASSERT(test_doubles(grib_ieee64_to_long, grib_long_to_ieee64) == 1);
printf("Test integers...\n");
/* test(3242539564, grib_ieee_to_long, grib_long_to_ieee); This fails! */
ECCODES_ASSERT(grib_ieee_to_long(grib_long_to_ieee(i)) == i);
/* The minimum value for which we can convert a long to ieee and back is 0x800000 */
/* The maximum value for which we can convert a long to ieee and back is 0x7f800000 */
for (i = 0x800000; i < 0x7f800000; i++) {
/*unsigned long j = i | 0x80000000;*/
if (grib_ieee_to_long(grib_long_to_ieee(i)) != i) {
printf("i=%lu i=%lx e=%g x=%lx\n", i, i, grib_long_to_ieee(i), grib_ieee_to_long(grib_long_to_ieee(i)));
/*ECCODES_ASSERT(grib_ieee_to_long(grib_long_to_ieee(i)) == i);*/
ECCODES_ASSERT(0);
}
/*if(grib_ieee_to_long(grib_long_to_ieee(j)) != j)
{
printf("j=%ld i=%lx e=%g x=%lx\n",j,j,grib_long_to_ieee(j),grib_ieee_to_long(grib_long_to_ieee(j)));
}
if ((i%1000000) == 0) {
printf("i = %08lx(%ld) %08lx(%ld) %g %g\n", i,i,j,j,grib_long_to_ieee(i),grib_long_to_ieee(j));
}*/
}
#else
double ref1 = grib_long_to_ieee(grib_ieee_to_long(min));
double ref2 = grib_nearest_smaller_ieee_float(min);
double a = p(min, ref1);
double b = p(min, ref2);
double c = p(ref1, ref1);
double d = p(ref2, ref2);
ECCODES_ASSERT(min < max);
#endif
printf("ALL DONE\n");
return 0;
}
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