[blackcat] L2 The Distance Coefficient Ehlers Filter

25 oct 2020

Level: 2

Background

John F. Ehlers introuced the Distance Coefficient Ehlers Filter in his "Rocket Science for Traders" chapter 18 on 2001.


Function

Dr. Ehlers considered the gray shading levels as distances, he had away of computing filter coefficients in terms of sharpness of the edge. White is the maximum distance in one direction from the median gray, and black is the maximum distance in the other direction. In this sense, distance is a measure of departure from the edge, taking into account the edge sharpness. Transitioning to price charts, the difference in prices can be imagined as a distance. Recalling the Pythagorean Theorem (which the length of the hypotenuse of a triangle is equal to the sum of the squares of the lengths of the other two sides), Dr Ehlers applied it to the needs and say that a generalized length at any data sample is the square root of the sum of the squares of the price difference between that price and each of the prices back for the length of the filter window. The distances squared at each data point are the coefficients of the Ehlers filter.


Key Signal

Coef --> Ehlers filter coefficients array
Distance2 --> Distance array
Filt --> Ehlers filter output


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.

Remarks

The 15th 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.

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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.

25 oct 2020

Notas de prensa

Add buy and sell labels

26 oct 2020

Notas de prensa

Correct label bar_index issue