positive_mod       40 ext/date/lib/dow.c 	return 6 - positive_mod(j, 4) * 2;
positive_mod       51 ext/date/lib/dow.c 	y1 = positive_mod(y, 100);
positive_mod       53 ext/date/lib/dow.c 	dow = positive_mod((c1 + y1 + m1 + (y1 / 4) + d), 7);