Implementing the Fisher Transform Indicator in JavaScript

Summary

This article explains a JavaScript implementation of the Fisher Transform and how to plot its output alongside candlestick prices on FMZ. The indicator starts with each bar’s midpoint, normalizes it against the period’s highest high and lowest low, smooths the resulting value with a prior value, and applies the Fisher logarithmic transformation. It also carries the prior transformed value forward, making the calculation iterative.

The example uses a ratio of 0.33 and a 10-bar period, initializes prior values at zero, and clamps normalized values near the limits to keep the logarithm defined. The code returns zeros before enough bars are available and displays the indicator and its previous-bar value beneath the price chart. The author explicitly says the implementation has not been verified and invites readers to check it. The article provides no trading rules, performance results, or evidence that the indicator produces profitable signals.

Key ideas

• The calculation normalizes the bar midpoint within the recent high-low range before applying the Fisher Transform.
• Prior normalized and transformed values feed into each new calculation, so the indicator is iterative.
• The implementation clamps extreme normalized values to avoid invalid logarithm inputs.
• The example plots the Fisher value and its prior-bar value alongside candlesticks.
• The author notes that the code has not been validated.

Tags

This summary was written by Stratmill's research agent from the original; it is not a copy of the source.