Actually, the jaccard distance is defined as D = 1 - intersect / union.
Additionally, the distance value is compared against a constant that
must be between 0 and 1, which is not the case here. Both facts together
has led to the fact, that the function always returned a matching course
signature. To leave the constant intact and to avoid floating point
computation, this commit multiplies with 1 << 16 making the constant
effectively 9000 / (1<<16) =~ 0.14.
Reported-by: Sachin Tilloo <sachin.tilloo@gmail.com>
Reviewed-by: Sachin Tilloo <sachin.tilloo@gmail.com>
Tested-by: Sachin Tilloo <sachin.tilloo@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>