mql5/Indicators/MyIndicators/TSI_Pro_Suite.md

True Strength Index (TSI) Pro Suite

1. Summary (Introduction)

The True Strength Index (TSI), developed by William Blau, is a momentum oscillator designed to provide a smoother and more reliable measure of market momentum than traditional indicators. It fluctuates around a zero line, providing clear signals for trend direction, momentum, and overbought/oversold conditions.

Our professional implementation, the TSI Pro Suite, modernizes this classic indicator by offering:

• Extended Smoothing Types: Ability to replace the standard EMAs with SMA, DEMA, TEMA, etc., for both the core calculation and the signal line.
• Full Heikin Ashi Support: Seamless integration with Heikin Ashi price data.
• Modular Design: A unified calculation engine powering both the line and oscillator versions.

The suite consists of:

1. TSI_Pro: The classic implementation (TSI Line + Signal Line).
2. TSI_Oscillator_Pro: A histogram version displaying the difference between the TSI and its Signal Line.

2. Mathematical Foundations

The TSI is calculated by double-smoothing both the price momentum and the absolute price momentum.

Calculation Steps

1. Momentum: Calculate the change in price from the previous bar.
   • M = P_i - P_{i-1}
2. First Smoothing (Slow): Apply a moving average (typically EMA) to both M and |M| over the Slow Period.
3. Second Smoothing (Fast): Apply a moving average to the results of the first step over the Fast Period.
4. TSI Value:
   • \text{TSI} = 100 \times \frac{\text{DoubleSmoothed}(M)}{\text{DoubleSmoothed}(|M|)}
5. Signal Line: A moving average of the TSI line.
6. Oscillator: \text{TSI} - \text{Signal Line}.

3. MQL5 Implementation Details

• Unified Calculator Engine: Both indicators use the TSI_Calculator.mqh engine. This ensures mathematical consistency.
• O(1) Incremental Calculation: Optimized for high performance. The indicators process only new bars (prev_calculated), ensuring zero lag.
• Composition: The calculator internally uses 5 instances of our MovingAverage_Engine to handle the various smoothing steps flexibly.

4. Parameters

TSI Calculation Settings

• Slow Period: Lookback for the first smoothing (Default: 25).
• Slow MA Type: Smoothing method for the first step (Default: EMA).
• Fast Period: Lookback for the second smoothing (Default: 13).
• Fast MA Type: Smoothing method for the second step (Default: EMA).
• Price Source: Selects the input data (Standard or Heikin Ashi).

Signal Line Settings

• Signal Period: Lookback for the signal line (Default: 13).
• Signal MA Type: Smoothing method for the signal line (Default: EMA).

5. Usage and Interpretation

TSI Line (TSI_Pro)

• Signal Crossover: Buy when TSI crosses above Signal; Sell when TSI crosses below Signal.
• Zero Line: Crossover indicates long-term trend change.
• Divergence: Divergences between TSI and price often precede reversals.

TSI Oscillator (TSI_Oscillator_Pro)

• Histogram: Visualizes the momentum strength. Growing bars = accelerating momentum. Shrinking bars = decelerating momentum.
• Zero Cross: Corresponds to the TSI/Signal crossover.