diff --git a/m1rc3/norruption/2/plot-corr b/m1rc3/norruption/2/plot-corr
index a8deee2..058777a 100755
--- a/m1rc3/norruption/2/plot-corr
+++ b/m1rc3/norruption/2/plot-corr
@@ -2,34 +2,45 @@
 
 sub usage
 {
-	print STDERR "usage: $0 [-s] [log_file]\n";
+	print STDERR "usage: $0 [-s [-n samples] [-i interval]] [log_file]\n";
 	exit(1);
 }
 
 
-if ($ARGV[0] eq "-s") {
-	shift @ARGV;
-	$sim = 1;
+while ($ARGV[0] =~ /^-/) {
+	$opt = shift @ARGV;
+	if ($opt eq "-s") {
+		$sim = 1;
+	} elsif ($opt eq "-n") {
+		$sim_n = shift @ARGV;
+		&usage unless defined $sim_n;
+	} elsif ($opt eq "-i") {
+		$sim_t = shift @ARGV;
+		&usage unless defined $sim_t;
+	} else {
+		&usage;
+	}
 }
-&usage if $ARGV[0] =~ /^-/;
 
-$n = 1;
-while (<>) {
-	next unless /^=== (\d+) ===/;
-	while ($1 != $n) {
-		push(@f, $n);
+unless ($sim && defined $sim_n && defined $sim_t) {
+	$n = 1;
+	while (<>) {
+		next unless /^=== (\d+) ===/;
+		while ($1 != $n) {
+			push(@f, $n);
+			$n++;
+		}
 		$n++;
 	}
-	$n++;
-}
 
-$n--;
-$t = int($n/@f+0.5);
+	$n--;
+	$t = int($n/@f+0.5);
 
-$last = 0;
-for (@f) {
-	push(@d, $_-$last);
-	$last = $_;
+	$last = 0;
+	for (@f) {
+		push(@d, $_-$last);
+		$last = $_;
+	}
 }
 
 if ($sim) {
@@ -39,9 +50,11 @@ if ($sim) {
 	# -T*ln(1-y) = x
 
 	$type = " (SIMULATED)";
+	$sim_n = @f unless defined $sim_n;
+	$sim_t = $t unless defined $sim_t;
 	@d = ();
-	for ($i = 0; $i != @f; $i++) {
-		push(@d, -$t*log(1-rand));
+	for ($i = 0; $i != $sim_n; $i++) {
+		push(@d, -$sim_t*log(1-rand));
 	}
 }