Ehlers Reflex Indicator [CC]The Reflex Indicator was created by John Ehlers (Stocks and Commodities Feb 2020) and this is a zero lag indicator that works similar to an overbought/oversold indicator but with the current stock cycle data. I find that this indicator works well as a leading indicator as well as a divergence indicator. Generally speaking, this indicator indicates a medium to long term downtrend when the indicator is below the line and a medium to long term uptrend when the indicator is above the line. Ehlers has created a few complementary indicators that I will release in the next few days but just keep in mind that this indicator focuses on the underlying cycle component while removing as much noise with no lag. I have color coded the lines to show strong signals with the darker colors and normal signals with the lighter colors. Buy when the line turns green and sell when it turns red.
Let me know if there are any other scripts you would like to see me publish!
Trendflex
Medium Term Weighted Stochastic (STPMT) by DGTLa Stochastique Pondérée Moyen Terme (STPMT) , or Mᴇᴅɪᴜᴍ Tᴇʀᴍ Wᴇɪɢʜᴛᴇᴅ Sᴛᴏᴄʜᴀꜱᴛɪᴄꜱ created by Eric Lefort in 1999, a French trader and author of trading books
█ The STPMT indicator is a tool which concerns itself with both the direction and the timing of the market. The STPMT indicator helps the trader with:
The general trend by observing the level around which the indicator oscillates
The changes of direction in the market
The timing to open or close a position by observing the oscillations and by observing the relative position of the STPMT versus its moving average
STPMT Calculation
stpmt = (4,1 * stoch(5, 3) + 2,5 * stoch(14, 3) + stoch(45, 14) + 4 * stoch(75, 20)) / 11.6
Where the first argument of the stoch function representation above is period (length) of K and second argument smoothing period of K. The result series is then plotted as red line and its moving average as blue line. By default disabled gray lines are the components of the STPMT
The oscillations of the STPMT around its moving average define the timing to open a position as crossing of STMP line and moving average line in case when both trends have same direction. The moving average determines the direction.
Long examples
█ Tʜᴇ CYCLE Iɴᴅɪᴄᴀᴛᴏʀ is derived from the STPMT. It is
cycle = stpmt – stpmt moving average
It is indicates more clearly all buy and sell opportunities. On the other hand it does not give any information on market direction. The Cycle indicator is a great help in timing as it allows the trader to more easily see the median length of an oscillation around the average point. In this way the traders can simply use the time axis to identify both a favorable price and a favorable moment. The Cycle Indicator is presented as histogram
The Lefort indicators are not a trading strategy. They are tools for different purposes which can be combined and which can serve for trading all instruments (stocks, market indices, forex, commodities…) in a variety of time frames. Hence they can be used for both day trading and swing trading.
👉 For whom that would like simple version of the Cycle indicator on top of the main price chart with signals as presented below.
Please note that in the following code STMP moving average direction is not considered and will plot signals regardless of the direction of STMP moving average. It is not a non-repainting version too.
here is pine code for the overlay version
// © dgtrd
//@version=4
study("Medium Term Weighted Stochastic (STPMT) by DGT", "STPMT ʙʏ DGT ☼☾", true, format.price, 2, resolution="")
i_maLen = input(9 , "Stoch MA Length", minval=1)
i_periodK1 = input(5 , "K1" , minval=1)
i_smoothK1 = input(3 , "Smooth K1", minval=1)
i_weightK1 = input(4.1 , "Weight K1", minval=1, step=.1)
i_periodK2 = input(14 , "K2" , minval=1)
i_smoothK2 = input(3 , "Smooth K2", minval=1)
i_weightK2 = input(2.5 , "Weight K2", minval=1, step=.1)
i_periodK3 = input(45 , "K3" , minval=1)
i_smoothK3 = input(14 , "Smooth K3", minval=1)
i_weightK3 = input(1. , "Weight K3", minval=1, step=.1)
i_periodK4 = input(75 , "K4" , minval=1)
i_smoothK4 = input(20 , "Smooth K4", minval=1)
i_weightK4 = input(4. , "Weight K4", minval=1, step=.1)
i_data = input(false, "Components of the STPMT")
//------------------------------------------------------------------------------
// stochastic function
f_stoch(_periodK, _smoothK) => sma(stoch(close, high, low, _periodK), _smoothK)
//------------------------------------------------------------------------------
// calculations
// La Stochastique Pondérée Moyen Terme (STPMT) or Medium Term Weighted Stochastics calculation
stpmt = (i_weightK1 * f_stoch(i_periodK1, i_smoothK1) + i_weightK2 * f_stoch(i_periodK2, i_smoothK2) + i_weightK3 * f_stoch(i_periodK3, i_smoothK3) + i_weightK4 * f_stoch(i_periodK4, i_smoothK4)) / (i_weightK1 + i_weightK2 + i_weightK3 + i_weightK4)
stpmt_ma = sma(stpmt, i_maLen) // STPMT Moving Average
cycle = stpmt - stpmt_ma // Cycle Indicator
//------------------------------------------------------------------------------
// plotting
plotarrow(change(sign(cycle)), "STPMT Signals", color.green, color.red, 0, maxheight=41)
alertcondition(cross(cycle, 0), title="Trading Opportunity", message="STPMT Cycle : Probable Trade Opportunity {{exchange}}:{{ticker}}-> Price = {{close}}, Time = {{time}}")
[blackcat] L2 Ehlers Trendflex CrossLevel: 2
Background
John F. Ehlers introuced Trendflex indicator in Feb, 2020.
Function
In “Reflex: A New Zero-Lag Indicator” in Feb, 2020, John Ehlers introduces a new averaging indicator that he has designed with reducing lag in mind. According to the Dr. Ehlers, this new indicator can be used to generate signals in a more timely manner than other lagging calculations. The script displays the trendflex indicator discussed in the article. The reflex indicator synchronizes with the cycle component in the price data. Its companion, the trendflex oscillator, retains the trend component.
Key Signal
FastTF --> Ehlers Trendflex fast line
SlowTF --> Ehlers Trendflex slow line
Pros and Cons
100% John F. Ehlers definition translation, even variable names are the same. This help readers who would like to use pine to read his book.
Remarks
The 94th script for Blackcat1402 John F. Ehlers Week publication.
Readme
In real life, I am a prolific inventor. I have successfully applied for more than 60 international and regional patents in the past 12 years. But in the past two years or so, I have tried to transfer my creativity to the development of trading strategies. Tradingview is the ideal platform for me. I am selecting and contributing some of the hundreds of scripts to publish in Tradingview community. Welcome everyone to interact with me to discuss these interesting pine scripts.
The scripts posted are categorized into 5 levels according to my efforts or manhours put into these works.
Level 1 : interesting script snippets or distinctive improvement from classic indicators or strategy. Level 1 scripts can usually appear in more complex indicators as a function module or element.
Level 2 : composite indicator/strategy. By selecting or combining several independent or dependent functions or sub indicators in proper way, the composite script exhibits a resonance phenomenon which can filter out noise or fake trading signal to enhance trading confidence level.
Level 3 : comprehensive indicator/strategy. They are simple trading systems based on my strategies. They are commonly containing several or all of entry signal, close signal, stop loss, take profit, re-entry, risk management, and position sizing techniques. Even some interesting fundamental and mass psychological aspects are incorporated.
Level 4 : script snippets or functions that do not disclose source code. Interesting element that can reveal market laws and work as raw material for indicators and strategies. If you find Level 1~2 scripts are helpful, Level 4 is a private version that took me far more efforts to develop.
Level 5 : indicator/strategy that do not disclose source code. private version of Level 3 script with my accumulated script processing skills or a large number of custom functions. I had a private function library built in past two years. Level 5 scripts use many of them to achieve private trading strategy.
Reflex & Trendflex█ OVERVIEW
Reflex and Trendflex are zero-lag oscillators that decompose price into independent cycle and trend components using SuperSmoother filtering. These indicators isolate each component separately, providing clearer identification of cyclical reversals (Reflex) versus trending movements (Trendflex).
Based on Dr. John F. Ehlers' "Reflex: A New Zero-Lag Indicator" article (February 2020, TASC), both oscillators use normalized slope deviation analysis to minimize lag while maintaining signal clarity. The SuperSmoother filter removes high-frequency noise, then deviations from linear regression (Reflex) or current value (Trendflex) are measured and normalized by RMS for consistent amplitude across instruments and timeframes.
█ CONCEPTS
SuperSmoother Filter
Both oscillators begin with a two-pole Butterworth low-pass filter that smooths price data without the excessive lag of simple moving averages. The filter uses exponential decay coefficients and cosine modulation based on the cutoff period, providing aggressive smoothing while preserving signal timing.
Reflex: Cycle Component
Reflex isolates cyclical price behavior by measuring deviation from a linear regression line fitted through the SuperSmoother output. For each bar, the filter calculates a linear slope over the lookback period, then sums how much the smoothed price deviates from this trendline. These deviations represent pure cyclical movement - price oscillations around the dominant trend. The result is normalized by RMS (root mean square) to produce consistent amplitude regardless of volatility or timeframe.
Trendflex: Trend Component
Trendflex extracts trending behavior by measuring cumulative deviation from the current SuperSmoother value. Instead of comparing to a regression line, it simply sums the differences between the current smoothed value and all past values in the period. This captures sustained directional movement rather than oscillations. Like Reflex, normalization by RMS ensures comparable readings across different instruments.
RMS Normalization
Both oscillators normalize their raw deviation measurements using an exponentially weighted RMS calculation: `rms = 0.04 * deviation² + 0.96 * rms `. This adaptive normalization ensures the oscillator amplitude remains stable as volatility changes, making threshold levels meaningful across different market conditions.
█ INTERPRETATION
Reflex (Cycle Component)
Oscillates around zero representing cyclical price behavior isolated from trend:
• Above zero : Price is in upward phase of cycle
• Below zero : Price is in downward phase of cycle
• Zero crossings : Potential cycle reversal points
• Extremes : Indicate stretched cyclical condition, often precede mean reversion
Best used for identifying cyclical turning points in ranging or oscillating markets. More sensitive to reversals than Trendflex.
Trendflex (Trend Component)
Oscillates around zero representing trending behavior isolated from cycles:
• Above zero : Sustained upward trend
• Below zero : Sustained downward trend
• Zero crossings : Trend direction changes
• Magnitude : Strength of trend (larger absolute values = stronger trend)
Best used for confirming trend direction and identifying trend exhaustion. Less noisy than Reflex due to focus on directional movement rather than oscillations.
Combined Analysis
Using both oscillators together provides powerful signal confirmation:
• Both positive: Strong uptrend with positive cycle phase (high probability long setup)
• Both negative: Strong downtrend with negative cycle phase (high probability short setup)
• Divergent signals: Conflicting cycle and trend (choppy conditions, reduce position size)
• Reflex reversal with Trendflex agreement: Cyclical turn within established trend (entry/exit timing)
Dynamic Thresholds
Threshold bands identify statistically significant oscillator readings that warrant attention:
• Breach above +threshold : Strong bullish cycle (Reflex) or trend (Trendflex) behavior - potential overbought condition
• Breach below -threshold : Strong bearish cycle or trend behavior - potential oversold condition
• Return inside thresholds : Signal strength normalizing, potential reversal or consolidation ahead
• Threshold compression : During low volatility, thresholds narrow (especially with StdDev mode), making breaches more frequent
• Threshold expansion : During high volatility, thresholds widen, filtering out minor oscillations
Combine threshold breaches with zero-line position for stronger signals:
• Threshold breach + zero-line cross = high-conviction signal
• Threshold breach without zero-line support = monitor for confirmation
Alert Conditions
Six built-in alerts trigger on bar close (no repainting):
• Above +Threshold : Oscillator crossed above positive threshold (strong bullish behavior)
• Below -Threshold : Oscillator crossed below negative threshold (strong bearish behavior)
• Reflex Above Zero : Reflex crossed above zero (bullish cycle phase)
• Reflex Below Zero : Reflex crossed below zero (bearish cycle phase)
• Trendflex Above Zero : Trendflex crossed above zero (bullish trend shift)
• Trendflex Below Zero : Trendflex crossed below zero (bearish trend shift)
█ SETTINGS & PARAMETER TUNING
Oscillator Settings
• Source : Price series to decompose
• Reflex Period (5-50): SuperSmoother period for cycle component. Lower values increase responsiveness to cyclical turns but add noise. Default 20.
• Trendflex Period (5-50): SuperSmoother period for trend component. Lower values respond faster to trend changes. Default 20.
Display Settings
• Reflex/Trendflex Display : Toggle visibility and customize colors for each oscillator independently
• Zero Line : Reference line showing neutral oscillator position
Dynamic Thresholds
Optional significance bands that identify when oscillator readings indicate strong cyclical or trending behavior:
• Threshold Mode : Choose calculation method based on market characteristics
- MAD (Median Absolute Deviation) : Outlier-resistant, best for markets with occasional spikes (default)
- Standard Deviation : Volatility-sensitive, adapts quickly to regime changes
- Percentile Rank : Fixed probability bands (e.g., 90% = only 10% of values exceed threshold)
• Apply To : Select which oscillator (Reflex or Trendflex) to calculate thresholds for
• Period (2-200): Lookback window for threshold calculation. Default 50.
• Multiplier (k) : Scaling factor for MAD/StdDev modes. Higher values = fewer threshold breaches (default 1.5)
• Percentile (%) : For Percentile mode only. Higher percentile = more selective threshold (default 90%)
Parameter Interactions
• Shorter periods make both oscillators more sensitive but noisier
• Reflex typically more volatile than Trendflex at same period settings
• For ranging markets: shorter Reflex period (10-15) captures swings better
• For trending markets: shorter Trendflex period (10-15) follows trend shifts faster
█ LIMITATIONS
Inherent Characteristics
• Near-zero lag, not zero-lag : Despite the name, some lag remains from SuperSmoother filtering
• Normalization artifacts : RMS normalization can produce unusual readings during volatility regime changes
• Period dependency : Oscillator characteristics change significantly with different period settings - no "correct" universal parameter
Market Conditions to Avoid
• Very low volatility : Normalization amplifies noise in quiet markets, producing false signals
• Sudden gaps : SuperSmoother assumes continuous data; large gaps disrupt filter continuity requiring bars to stabilize
• Micro timeframes : Sub-minute charts contain microstructure noise that overwhelms signal quality
Parameter Selection Pitfalls
• Matching periods to dominant cycle : If period doesn't align with actual market cycle period, signals degrade
• Threshold over-tuning : Optimizing threshold parameters for past data often fails forward - use conservative defaults
• Ignoring component differences : Reflex and Trendflex measure different aspects - don't expect identical behavior
█ NOTES
Credits
These indicators are based on Dr. John F. Ehlers' "Reflex: A New Zero-Lag Indicator" published in the February 2020 issue of Technical Analysis of Stocks & Commodities (TASC) magazine. The article introduces a novel approach to isolating cycle and trend components using SuperSmoother filtering combined with normalized deviation analysis.
For those interested in the underlying mathematics and DSP concepts:
• Ehlers, J.F. (February 2020). "Reflex: A New Zero-Lag Indicator" - Technical Analysis of Stocks & Commodities magazine
• Ehlers, J.F. (2001). Rocket Science for Traders: Digital Signal Processing Applications . John Wiley & Sons
• Various TASC articles by John Ehlers on SuperSmoother filters and oscillator design
by ♚@e2e4



