/*
 * Copyright (c) 1996 Ernest Bowen and Landon Curt Noll
 * Permission is granted to use, distribute, or modify this source,
 * provided that this copyright notice remains intact.
 *
 * By: Ernest Bowen and Landon Curt Noll
 *     ernie@neumann.une.edu.au and http://reality.sgi.com/chongo/
 *
 * This library is used by the 3500 series of the regress.cal test suite.
 */
/*
 * Stringent tests of the functions frem, fcnt, gcdrem.
 *
 * testf(n) gives n tests of frem(x,y) and fcnt(x,y) with randomly
 * 	integers x and y generated so that x = f * y^k where f, y and
 *	k are randomly generated.
 *
 * testg(n) gives n tests of gcdrem(x,y) with x and y generated as for
 *	testf(n).
 *
 * testh(n,N) gives n tests of g = gcdrem(x,y) where x and y are products of
 *	powers of small primes some of which are common to both x and y.
 *	This test uses f = abs(x) and iteratively f = frem(f,p) where
 *	p varies over the prime divisors of y; the final value for f
 *	should equal g.  For both x and y the primes are raised to the
 *	power rand(N); N defaults to 10.
 *
 * If verbose is > 1, the numbers x, y and values for some of the
 *	functions will be displayed.  Numbers used in testf()
 *	and testg() occasionally have thousands of digits.
 *
 */

global defaultverbose = 1;	/* default verbose value */
global err;

define testfrem(x,y,verbose)
{
	local f, n;

	if (isnull(verbose)) verbose = defaultverbose;

	f = frem(x,y);
	n = fcnt(x,y);
	if (verbose > 1)
		printf("frem = %d, fcnt = %d\n\n", f, n);
	if (abs(x) != f * abs(y)^n)
		return 1;
	if (!ismult(x,y) || abs(y) <= 1) {
		if (f != abs(x))
			return 2;
		if (n != 0)
			return 3;
		return 0;
	}
	if (x == 0) {
		if (f != 0 || n != 0)
			return 4;
		return 0;
	}
	if (f < 0 || !isint(f) || n <= 0)
		return 5;
	if (ismult(f, y))
		return 6;
	if (!ismult(x, y^n))
		return 7;
	if (ismult(x, y^(n+1)))
		return 8;
	return 0;
}

define testgcdrem(x,y,verbose)
{
	local d, q;

	if (isnull(verbose)) verbose = defaultverbose;

	d = gcdrem(x,y);
	if (verbose > 1)
		printf("gcdrem = %d\n\n", d);
	if (y == 0) {
		if (d != 1)
			return 1;
		return 0;
	}
	if (x == 0) {
		if (d != 0)
			return 2;
		return 0;
	}
	if (d <= 0)
		return 3;
	q = x/d;
	if (!isint(q))
		return 4;
	if (!isrel(d, y))
		return 5;
	if (!isrel(d, q))
		return 6;
	return 0;
}

define testf(str,n,verbose)
{
	local m, x, y, i, k, y1, f1, f, fail;

	if (isnull(verbose))
		verbose = defaultverbose;
	if (verbose > 0) {
		print str:":",:;
	}
	m = 0;
	for (i = 0; i < n; i++) {
		y1 = rand(2^rand(1,6));
		y = rand(-(2^y1), 1 + 2^y1);
		f1 = rand(2^rand(1,11));
		f = rand(-(2^f1), 1+2^f1);
		k = rand(1,1+2^10);
		x = f * y^k;
		if (verbose > 1) {
			printf("x = %d\n", x);
			printf("y = %d\n", y);
		}
		fail = testfrem(x,y,verbose);
		if (fail != 0) {
			printf("*** Failure %d on loop %d\n", fail, i);
			if (verbose > 1) {
				printf("    x = %d\n", x);
				printf("    y = %d\n", y);
			}
			m++;
		}
	}

	if (verbose > 0) {
		if (m) {
			printf("*** %d error(s)\n", m);
		} else {
			printf("no errors\n");
		}
	}
	return m;
}


define testg(str,n,verbose)
{
	local m, x, y, i, k, y1, f1, f, fail;

	if (isnull(verbose))
		verbose = defaultverbose;
	if (verbose > 0) {
		print str:":",:;
	}
	m = 0;
	for (i = 0; i < n; i++) {
		y1 = rand(2^rand(1,6));
		y = rand(-(2^y1), 1 + 2^y1);
		f1 = rand(2^rand(1,11));
		f = rand(-(2^f1), 1+2^f1);
		k = rand(1,1+2^10);
		x = f * y^k;
		if (verbose > 1) {
			printf("x = %d\n", x);
			printf("y = %d\n", y);
		}
		fail = testgcdrem(x,y,verbose);
		if (fail != 0) {
			printf("*** Failure %d on loop %d\n", fail, i);
			if (verbose > 1) {
				printf("    x = %d\n", x);
				printf("    y = %d\n", y);
			}
			m++;
		}
	}

	if (verbose > 0) {
		if (m) {
			printf("*** %d error(s)\n", m);
		} else {
			printf("no errors\n");
		}
	}
	return m;
}

define testh(str,n,N,verbose)
{
	local m, i, x, y, f, g;

	if (isnull(verbose))
		verbose = defaultverbose;
	if (verbose > 0) {
		print str:":",:;
	}
	m = 0;
	if (isnull(N))
		N = 61;
	for (i = 0; i < n; i ++) {
		x = 2^rand(N)*3^rand(N) * 7^rand(N) * 11^rand(N) * 101^rand(N);
		y = 2^rand(N) * 3^rand(N) * 5^rand(N) * 11^rand(N) * 53^rand(N);
		if (rand(2)) x = -x;
		if (rand(2)) y = -y;

		if (verbose > 1) {
			printf("x = %d\n", x);
			printf("y = %d\n", y);
		}
		f = abs(x);
		g = gcdrem(x,y);
		if (ismult(y,2)) f = frem(f,2);
		if (ismult(y,3)) f = frem(f,3);
		if (ismult(y,5)) f = frem(f,5);
		if (ismult(y,11)) f = frem(f,11);
		if (ismult(y,53)) f = frem(f,53);

		if (f != g) {
			printf("*** Failure on loop %d\n", i);
			if (verbose > 1) {
				printf("    x = %d\n", x);
				printf("    y = %d\n", y);
				printf("    f = %d\n", f);
				printf("    g = %d\n", g);
			}
			m++;
		}
	}

	if (verbose > 0) {
		if (m) {
			printf("*** %d error(s)\n", m);
		} else {
			printf("no errors\n");
		}
	}
	return m;
}

/*
 * test3500 - perform all of the above tests a bunch of times
 */
define test3500(verbose, tnum, n, N)
{
	/* set test parameters */
	if (isnull(verbose)) {
		verbose = defaultverbose;
	}
	if (isnull(tnum)) {
		tnum = 3501;	/* default test number */
	}
	if (isnull(n)) {
		n = 200;
	}
	if (isnull(N)) {
		N = 61;
	}

	/*
	 * test a lot of stuff
	 */
	srand(3500e3500);
	err += testf(strcat(str(tnum++), ": frem/fcnt"), n, verbose);
	err += testg(strcat(str(tnum++), ": gcdrem"), n, verbose);
	err += testh(strcat(str(tnum++),": gcdrem #2"), n, N, verbose);
	if (verbose > 1) {
		if (err) {
			print "***", err, "error(s) found in testall";
		} else {
			print "no errors in testall";
		}
	}
	return tnum;
}