Porcupine

Displays "spike days" by colouring the bars (Default: yellow for a Spike High and blue for a Spike Low)

Spike Day's definition taken from Jack D Schwager's Book: A Complete Guide to the Futures Market: Technical Analysis, Trading Systems, Fundamental Analysis, Options, Spreads, and Trading Principles


A spike is:

• A wide difference between the spike high and the highs of the preceding and succeeding days.
  
• A close near the low of the day's range.
  
• A substantial price advance preceding the spike's formation.
  

The more extreme each of these conditions, the greater the likelihood that a spike high will prove to be an important relative high or even a major top.

(inverse is true for lows, basically)


Enjoy!