ADX_RD

ADX_RD - Average Directional Index (Ryan DeBraal)
This script plots a refined version of the **ADX (Average Directional Index)**,
used to measure trend strength regardless of trend direction. It includes
custom smoothing, modified DM (Directional Movement) logic, dynamic coloring,
and a built-in 20-level threshold.

FEATURES
- Calculates +DI, –DI, and ADX using standard Wilder smoothing (RMA).
- Signal color turns **white** when ADX < 20 (low-trend or choppy conditions).
- Signal color turns **blue** when ADX >= 20 (trend strengthening).
- Horizontal dotted reference line at **20**, a widely used threshold:
ADX < 20 → weak or ranging market
ADX > 20 → strengthening trend
- Works on all timeframes, supports custom smoothing lengths.

PURPOSE
This indicator helps identify when a market is trending vs when it is flat.
It does not indicate direction by itself — only the strength of the move —
making it ideal for confirming breakout setups, trend-following entries,
and filtering out low-probability trades during chop.