מעודכן
[blackcat] L3 Ehlers ZeroLag Intraday Trading System
Level: 3
Background
John F. Ehlers introuced ZeroLag Intraday Trading System in his "Rocket Science for Traders" chapter 16.
Function
blackcat L3 EhlersZeroLag Intraday Trading System is used to find proper long and short entries. Dr. Ehlers developed a completely automatic ZeroLag Intraday Trading System. The concepts of the Instantaneous Trendline and the ZeroLag EMA are very powerful. To demonstrate just how profound these concepts are, Dr. Ehlers designed an intraday trading system. An intraday trade is defined as any active trade that is traded and then closed at the end of the day.
Key Signal
Smooth --> 4 bar WMA w/ 1 bar lag
Detrender --> The amplitude response of a minimum-length HT can be improved by adjusting the filter coefficients by
trial and error. HT does not allow DC component at zero frequency for transformation. So, Detrender is used to remove DC component/ trend component.
Q1 --> Quadrature phase signal
I1 --> In-phase signal
Period --> Dominant Cycle in bars
SmoothPeriod --> Period with complex averaging
DCPeriod ---> Dominant Cycle Period
Trendline ---> IT fast line
ZeroLag ---> Zero Lag Filter
long ---> long entry signal
short ---> short entry signal
Pros and Cons
100% John F. Ehlers definition translation of original work, even variable names are the same. This help readers who would like to use pine to read his book. If you had read his works, then you will be quite familiar with my code style.
NOTE: This version of Trading System has better preformance than "Automatic SineTrend Trading System".
Remarks
The 12th 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.
Background
John F. Ehlers introuced ZeroLag Intraday Trading System in his "Rocket Science for Traders" chapter 16.
Function
blackcat L3 EhlersZeroLag Intraday Trading System is used to find proper long and short entries. Dr. Ehlers developed a completely automatic ZeroLag Intraday Trading System. The concepts of the Instantaneous Trendline and the ZeroLag EMA are very powerful. To demonstrate just how profound these concepts are, Dr. Ehlers designed an intraday trading system. An intraday trade is defined as any active trade that is traded and then closed at the end of the day.
Key Signal
Smooth --> 4 bar WMA w/ 1 bar lag
Detrender --> The amplitude response of a minimum-length HT can be improved by adjusting the filter coefficients by
trial and error. HT does not allow DC component at zero frequency for transformation. So, Detrender is used to remove DC component/ trend component.
Q1 --> Quadrature phase signal
I1 --> In-phase signal
Period --> Dominant Cycle in bars
SmoothPeriod --> Period with complex averaging
DCPeriod ---> Dominant Cycle Period
Trendline ---> IT fast line
ZeroLag ---> Zero Lag Filter
long ---> long entry signal
short ---> short entry signal
Pros and Cons
100% John F. Ehlers definition translation of original work, even variable names are the same. This help readers who would like to use pine to read his book. If you had read his works, then you will be quite familiar with my code style.
NOTE: This version of Trading System has better preformance than "Automatic SineTrend Trading System".
Remarks
The 12th 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.
הערות שחרור
OVERVIEWThe **[blackcat] L3 Ehlers ZeroLag Intraday Trading System** is a technical analysis script designed to generate buy and sell signals based on Ehlers' ZeroLag filtering method. It uses a combination of Hilbert Transform and Homodyne Discriminator to identify trends and potential reversal points, providing traders with actionable signals for intraday trading.
FEATURES
ZeroLag Filtering: Utilizes advanced filtering techniques to smooth price data and identify trends.
Hilbert Transform: Extracts the in-phase and quadrature components of the price signal.
Homodyne Discriminator: Discriminates between trend and noise to enhance signal clarity.
Trendline Calculation: Determines the dominant cycle period and calculates a trendline based on this period.
Trading Signals: Generates buy and sell signals based on the relationship between the ZeroLag filter and the trendline.
HOW TO USE
Add the script to your TradingView chart.
Adjust the Source input to your preferred price series (e.g., hl2 for high-low midpoint).
Modify the alpha value to fine-tune the smoothing factor (default is 0.33).
The script will plot buy signals below the chart and sell signals above the chart when conditions are met.
LIMITATIONS
The script is optimized for intraday trading and may not perform well on longer timeframes.
Signal quality can vary based on market conditions and chosen parameters.
הערות שחרור
█ OVERVIEWThis intraday trading system combines John Ehlers' adaptive Instantaneous Trendline with a zero-lag filter, and only fires when the day qualifies as an outside day. It plots both lines on the chart, marks BUY / SELL entries, tracks a position state, and projects ATR-based stop-loss and take-profit levels from each entry.
█ CONCEPTS
The system measures the market's dominant cycle with a Hilbert Transform, builds an adaptive trendline over that measured cycle, then compares it against a zero-lag smoothing of price. Trades are gated by an outside-day condition, which demands that today's range violates yesterday's range before any position is allowed.
Key principles:
• Adaptive trendline: the averaging length follows the measured dominant cycle (clamped 6-50 bars)
• Zero-lag filter: a predictive smoothing that compensates half of the 3-bar momentum term
• Outside-day gate: signals require today's high or low to exceed yesterday's range
• Two entry styles: second-bar momentum continuation and pullback crossover
█ HOW TO USE
1 — Add the indicator to an intraday chart (5m to 1h recommended) of a liquid instrument.
2 — Wait for an outside day: the panel shows YES when today's range breaks yesterday's range.
3 — Take BUY / SELL labels as entry triggers, and EXIT labels or the opposite crossover to close.
4 — Optionally arm the four alert conditions for hands-off monitoring.
Input Parameters
• Source: price series feeding the cycle engine and zero-lag filter (default hl2)
• Zero-Lag Alpha: smoothing factor of the zero-lag filter (default 0.33, range 0.01-0.99)
• Entry 1 — Second-Bar Momentum: toggle for the Ehlers original second-bar entry
• Entry 2 — Pullback Crossover: toggle for the crossover-with-pullback entry
• Enable ATR Stop / Target: master switch for the projected risk levels
• ATR Length / Stop-Loss ATR Multiple / Take-Profit ATR Multiple: risk projection sizing
• Cooldown Bars: minimum bars between any two signals (default 0 = disabled)
• Show Trendline / ZeroLag, Show Position Background, Show Status Panel: display toggles
█ FEATURES
• Adaptive Ehlers Instantaneous Trendline plus zero-lag filter plotted on-chart
• Dual entry engine: second-bar momentum and pullback crossover, each toggleable
• Bidirectional BUY / SELL signals with an outside-day session gate and cooldown filter
• Position state machine with EXIT labels on opposite crossover or risk-level touch
• ATR-based stop-loss and take-profit reference lines projected from each entry
• On-chart status panel: dominant cycle, ZeroLag, Trendline, outside-day flag, position, ATR, stop/target
• Four alertcondition entries plus a dynamic alert() for signal automation
█ SIGNALS
Visual Elements
• BUY (green label, below bar): entry-long trigger from either entry style
• SELL (red label, above bar): entry-short trigger from either entry style
• EXIT (orange label): position closed by opposite crossover or stop/target touch
• Orange Trendline vs aqua ZeroLag: the adaptive trend and the zero-lag price
• Red / green broken lines: stop-loss and take-profit levels of the open position
• Teal / red background tint: long / short position state
Entry Logic
• Entry 1 fires on the second bar of a new session: price must continue in the trend direction with the previous bar closing in the upper (long) or lower (short) third of its range
• Entry 2 fires when ZeroLag crosses the Trendline against a one-bar pullback, with the current bar closing in the favorable half of its range
• Both entries require the outside-day condition and respect the cooldown setting
█ IMPLEMENTATION NOTES
Open-source implementation built on the Ehlers Hilbert Transform pipeline: the homodyne discriminator estimates the dominant cycle period, which is clamped to 6-50 bars and smoothed before the trendline average is computed. The zero-lag filter adds half of the 3-bar momentum difference back into the smoothing. All stateful ta.* calls (crossover, crossunder, atr) execute unconditionally every bar, and signals are confirmed on bar close, so nothing repaints after the bar closes.
█ LIMITATIONS
• The outside-day gate suppresses signals on quiet sessions; trend days without range expansion are skipped
• Adaptive trendlines lag during violent V-shaped reversals
• Stop-loss / take-profit lines are visual references, not live orders
• Designed for intraday charts; behavior on daily+ timeframes is not the intended use case
• Historical signal behavior is not a promise of future results
█ NOTES
• Based on John F. Ehlers' ZeroLag intraday trading concepts (Cybernetic Analysis for Stocks and Futures)
• All thresholds are exposed as inputs; defaults preserve the original signal logic
• Free / open-source (MPL 2.0) — attribution appreciated
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For questions or feedback, use comments section below.
Feel free to use and modify — attribution appreciated.
Don't miss out! The first and most important thing to do is to join my Discord chat now! Click here to start your adventure: discord.com/invite/ZTGpQJq My new github for more pine development soon: github.com/wxt-coder
כתב ויתור
המידע והפרסומים אינם מיועדים להיות, ואינם מהווים, ייעוץ או המלצה פיננסית, השקעתית, מסחרית או מכל סוג אחר המסופקת או מאושרת על ידי TradingView. קרא עוד ב־תנאי השימוש.
Don't miss out! The first and most important thing to do is to join my Discord chat now! Click here to start your adventure: discord.com/invite/ZTGpQJq My new github for more pine development soon: github.com/wxt-coder
כתב ויתור
המידע והפרסומים אינם מיועדים להיות, ואינם מהווים, ייעוץ או המלצה פיננסית, השקעתית, מסחרית או מכל סוג אחר המסופקת או מאושרת על ידי TradingView. קרא עוד ב־תנאי השימוש.