#!/usr/bin/perl -w

# ----------------------------------------------------------------
# John Kerl
# kerl.john.r@gmail.com
# 2005-06-30
# See http://math.arizona.edu/~kerl/doc/ssdda.pdf for information.
# ----------------------------------------------------------------

use PMATLIB;

$sign = 1.0;
while (@ARGV) {
	last unless $ARGV[0] =~ m/^-/;
	if (pmatlib_opt(\@ARGV)) {
		;
	}
	elsif ($ARGV[0] eq "-inv") {
		$sign = -1.0;
		shift @ARGV;
	}
	else {
		usage();
	}
}

if (@ARGV != 1) {
	usage();
}
$n = shift @ARGV;

for ($i = 0; $i < $n; $i++) {
	for ($j = 0; $j < $n; $j++) {
		$A[$i][$j] = ($sign ** ($i+$j)) * binc($i, $j);
	}
}
print_matrix(\@A, $n, $n);

# ----------------------------------------------------------------
sub usage
{
	die
		"Usage: $0 [options] {n}\n" .
		"Options:\n" .
		pmatlib_options_string() .
		"  -inv: print the inverse of A.\n";
}