Original LUA indicator: http://fxcodebase.com/code/viewtopic.php?f=17&t=36543.
Formulas:
BL = (MinH+MaxH)/2,
BR = (MinL+MaxL)/2,
POB = (BL+BR)/2, where
MinH, MaxH - minimum and maximum HIGH prices at range from (i-Length) to i,
MinL, MaxL - minimum and maximum LOW prices at range from (i-Length) to i.
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