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/*
* Nickle test suite
*
* factorial tests
*/
int errors = 0;
int fact(int n) {
int r = 1;
while (n > 1) {
r *= n;
n--;
}
return r;
}
void check_factorial(int max) {
for (int n = 0; n < max; n++) {
int is = n!;
int should = fact(n);
if (is != should) {
printf ("check failed %d! (was %d should be %d)\n",
n, is, should);
++errors;
}
}
}
real stirling (real n)
{
n = imprecise (n);
return sqrt (2 * pi * n) * (n / Math::e) ** n;
}
void check_one_stirling(int v) {
real s = stirling(v);
real f = v!;
real r = f/s;
real e = 0.1/v;
if (r < 1 || r > (1 + e)) {
printf("check failed %d! (was %d should be close to %g)\n",
v, f, s);
++errors;
}
}
void check_stirling(int rep) {
real v = 13;
while (rep-- > 0) {
int iv = floor(v);
check_one_stirling(iv);
v = v * 3 + 2;
}
}
check_stirling(10);
check_factorial(1000);
exit (errors);
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