** Using WeBWorK **

For an assignment in a linear algebra unit, I've done the following: Give students 10 problems, 5 of which have unique answers, 3 of which have infinitely many answers, and 2 of which have no answers. For reasons dealing with the student population of the class, I've set these up as 10 separate problems. I don't want all students to have the same results: i.e., I don't want the answer to #7 to be "none" for every student.

I've use the following code:

# Give student same seed for every problem (code from forum)
$seed = 0; map {$seed += ord($_)} split(//,$studentID);
SRAND($seed);

@rr = (0,0,0,0,0,1,1,2,2,2);
# 0 represents unique answer
# 1 represents no answer
# 2 represents dependent system

# Shuffle @rr
# I know there are more efficient methods here...
for $i (0..9) {
$j = random(0,9);
$tmp = $rr[$i];
$rr[$i] = $rr[$j];
$rr[$j] = $tmp;
}

# Choose problem type
$r = $rr[$prob]; # $prob runs between 0 and 9, assigned earlier

$seed += 1421177; # Converted chapter/section/prob. num to octal
SRAND($seed);

This certainly works. I would, however, like to make things a little nicer, and give them a random seed at the end, rather than one based on their ID and the problem number. Is there a good way to do this?

Nathan