const Fix16 sdiv(const double other) const { Fix16 ret = fix16_sdiv(value, fix16_from_dbl(other)); return ret; }
const int operator!=(const double other) const { return (value != fix16_from_dbl(other)); }
int main()
{
int status = 0;
{
COMMENT("Testing fix16_exp() corner cases");
TEST(fix16_exp(0) == fix16_one);
TEST(fix16_exp(fix16_minimum) == 0);
TEST(fix16_exp(fix16_maximum) == fix16_maximum);
}
{
COMMENT("Testing fix16_exp() accuracy over -11..4");
fix16_t max_delta = -1;
fix16_t worst = 0;
fix16_t sum = 0;
int count = 0;
fix16_t a;
for (a = fix16_from_dbl(-11.0); a < fix16_from_dbl(4.0); a += 31)
{
fix16_t result = fix16_exp(a);
fix16_t resultf = fix16_from_dbl(exp(fix16_to_dbl(a)));
fix16_t d = delta(result, resultf);
if (d > max_delta)
{
max_delta = d;
worst = a;
}
sum += d;
count++;
}
printf("Worst delta %d with input %d\n", max_delta, worst);
printf("Average delta %0.2f\n", (float)sum / count);
TEST(max_delta < 200);
}
{
COMMENT("Testing fix16_exp() accuracy over full range");
float max_delta = -1;
fix16_t worst = 0;
float sum = 0;
int count = 0;
fix16_t a;
// Test the whole range of results 0..32768 with a bit less samples
for (a = -772243; a < 681391; a += 113)
{
fix16_t result = fix16_exp(a);
fix16_t resultf = fix16_from_dbl(exp(fix16_to_dbl(a)));
fix16_t d1 = delta(result, resultf);
if (d1 > 0) d1--; // Forgive +-1 for the fix16_t inaccuracy
float d = (float)d1 / resultf * 100;
if (resultf < 1000) continue; // Percentages can explode when result is almost 0.
if (d > max_delta)
{
max_delta = d;
worst = a;
}
sum += d;
count++;
}
printf("Worst delta %0.4f%% with input %d\n", max_delta, worst);
printf("Average delta %0.4f%%\n", sum / count);
TEST(max_delta < 1);
}
{
COMMENT("Testing fix16_log() accuracy over full range");
fix16_t max_delta = -1;
fix16_t worst = 0;
fix16_t sum = 0;
int count = 0;
fix16_t a;
for (a = 100; a > 0 && a < fix16_maximum - 7561; a += 7561)
{
fix16_t result = fix16_log(a);
fix16_t resultf = fix16_from_dbl(log(fix16_to_dbl(a)));
fix16_t d = delta(result, resultf);
if (d > max_delta)
{
max_delta = d;
worst = a;
}
sum += d;
count++;
}
printf("Worst delta %d with input %d\n", max_delta, worst);
printf("Average delta %0.2f\n", (float)sum / count);
TEST(max_delta < 20);
}
if (status != 0)
fprintf(stdout, "\n\nSome tests FAILED!\n");
return status;
}
const Fix16 ssub(const double other) const { Fix16 ret = fix16_sadd(value, -fix16_from_dbl(other)); return ret; }
Fix16 & operator/=(const double rhs) { value = fix16_div(value, fix16_from_dbl(rhs)); return *this; }
Fix16 & operator-=(const double rhs) { value -= fix16_from_dbl(rhs); return *this; }
Fix16(const double inValue) { value = fix16_from_dbl(inValue); }
