/*
* call-seq:
* bv.next_from(from) -> bit_num
*
* Returns the next set bit in the bit-vector scanning from low order to
* high order and starting at +from+. The scan is inclusive so if
* +from+ is equal to 10 and +bv[10]+ is set it will
* return the number 10. If the bit-vector has been negated than you should
* use the +#next_unset_from+ method.
*/
VALUE
frt_bv_next_from(VALUE self, VALUE rfrom)
{
BitVector *bv;
int from = FIX2INT(rfrom);
GET_BV(bv, self);
if (from < 0) {
from = 0;
}
return INT2FIX(bv_scan_next_from(bv, from));
}
/**
* Stress test BitVector Scanning as well as bv_set_fast. This test has been
* run successfully with BV_DENSE_SCAN_SIZE set to 20000000 and BV_SCAN_INC
* set to 97. When running this test with high numbers, be sure use -q on the
* command line or the test will take a very long time.
*/
static void test_bv_scan_stress(TestCase *tc, void *data)
{
int i;
BitVector *bv = bv_new_capa(BV_SCAN_SIZE);
BitVector *not_bv;
(void)data; /* suppress unused argument warning */
for (i = BV_SCAN_INC; i < BV_SCAN_SIZE; i += BV_SCAN_INC) {
bv_set_fast(bv, i);
Aiequal(bv_get(bv, i), 1);
Aiequal(bv_get(bv, i-1), 0);
Aiequal(bv_get(bv, i+1), 0);
}
not_bv = bv_not(bv);
for (i = BV_SCAN_INC; i < BV_SCAN_SIZE; i += BV_SCAN_INC) {
Aiequal(i, bv_scan_next_from(bv, i - BV_SCAN_INC / 2));
Aiequal(i, bv_scan_next_unset_from(not_bv, i - BV_SCAN_INC / 2));
}
Aiequal(-1, bv_scan_next_from(bv, i - BV_SCAN_INC / 2));
Aiequal(-1, bv_scan_next_unset_from(not_bv, i - BV_SCAN_INC / 2));
/* test scan_next_from where size is actually greater than the highest set
* bit */
bv_unset(bv, bv->size);
bv_set(not_bv, not_bv->size);
bv_scan_reset(bv);
bv_scan_reset(not_bv);
for (i = BV_SCAN_INC; i < BV_SCAN_SIZE; i += BV_SCAN_INC) {
Aiequal(i, bv_scan_next_from(bv, i - BV_SCAN_INC / 2));
Aiequal(i, bv_scan_next_unset_from(not_bv, i - BV_SCAN_INC / 2));
}
Aiequal(-1, bv_scan_next_from(bv, i - BV_SCAN_INC / 2));
Aiequal(-1, bv_scan_next_unset_from(not_bv, i - BV_SCAN_INC / 2));
bv_scan_reset(bv);
bv_scan_reset(not_bv);
for (i = BV_SCAN_INC; i < BV_SCAN_SIZE; i += BV_SCAN_INC) {
Aiequal(i, bv_scan_next(bv));
Aiequal(i, bv_scan_next_unset(not_bv));
}
Aiequal(-1, bv_scan_next(bv));
Aiequal(-1, bv_scan_next_unset(not_bv));
bv_clear(bv);
bv_destroy(not_bv);
for (i = 0; i < BV_DENSE_SCAN_SIZE; i++) {
bv_set(bv, i);
}
not_bv = bv_not(bv);
for (i = 0; i < BV_DENSE_SCAN_SIZE; i++) {
Aiequal(i, bv_scan_next_from(bv, i));
Aiequal(i, bv_scan_next_unset_from(not_bv, i));
}
Aiequal(-1, bv_scan_next_from(bv, i));
Aiequal(-1, bv_scan_next_unset_from(not_bv, i));
bv_scan_reset(bv);
bv_scan_reset(not_bv);
for (i = 0; i < BV_DENSE_SCAN_SIZE; i++) {
Aiequal(i, bv_scan_next(bv));
Aiequal(i, bv_scan_next_unset(not_bv));
}
Aiequal(-1, bv_scan_next(bv));
Aiequal(-1, bv_scan_next_unset(not_bv));
bv_destroy(bv);
bv_destroy(not_bv);
}
