This script detects harmonic formations: Gartley, Bat, Butterfly, and Crab.
Unlike the other harmonic scanners, it analyzes more than the last five consecutive points. It checks up to 50 last high/low points and tries to find a pattern there. It also labels point D with information on what type of formation it is and if it's a signal to sell or buy.
The default error margin for each formation is 5% (so each point can be up to 5% different than the ideal value defined in the books).
I don't have enough reputation for linking other charts, but check it out with BATS:V (Visa) and BATS:JPM (JPMorgan Chase) to see more formations.