Coppock Curve (Coppock) - Built-in Indicator Guide

Computes the Coppock Curve as a weighted moving average of the sum of two Rate of Change values.

Overview

The Coppock Curve is a long-term momentum oscillator that combines two Rate of Change (ROC) periods and smooths the result with a Weighted Moving Average (WMA). It is designed to identify major bottoms in price trends by capturing the acceleration of price changes. The indicator plots a single blue line on the chart, oscillating around zero.

How it works

1. Compute the long-term Rate of Change (ROC) over the user-defined long_roc_length period.
2. Compute the short-term ROC over the user-defined short_roc_length period.
3. Sum the two ROC values to create a combined momentum series.
4. Apply a Weighted Moving Average (WMA) of length wma_length to the summed series.
5. Plot the resulting smoothed curve as a blue line on the chart.

Mathematical model

where $L$ = long_roc_length, $S$ = short_roc_length, $W$ = wma_length.

Parameters

Code walkthrough

Parameter decorators

Lines 6-9 of Coppock Curve.indie5:

@indicator('Coppock')  # Coppock Curve
@param.int('wma_length', default=10, min=1, title='WMA Length')
@param.int('long_roc_length', default=14, min=1, title='Long RoC Length')
@param.int('short_roc_length', default=11, min=1, title='Short RoC Length')

The @indicator decorator sets the display name. Three integer parameters control the WMA length, long ROC length, and short ROC length, each with a default and minimum of 1. The @plot.line decorator specifies the output line color as blue.

ROC computation

Lines 12-13 of Coppock Curve.indie5:

    l_roc = Roc.new(self.close, long_roc_length)[0]
    s_roc = Roc.new(self.close, short_roc_length)[0]

Two independent ROC series are created using the built-in Roc algorithm applied to the close price. The [0] index retrieves the current bar’s value. The long and short lengths are user-defined, allowing flexibility in the momentum measurement windows.

WMA smoothing and return

Lines 14-15 of Coppock Curve.indie5:

    curve = Wma.new(MutSeriesF.new(l_roc + s_roc), wma_length)[0]
    return curve

The two ROC values are summed via MutSeriesF, which creates a mutable series from the computed sum. A WMA of that series is then calculated with the user-specified length. The final curve value is returned as a single float for plotting.

Reading the chart

• The blue line oscillates above and below zero.
• A crossing above zero may indicate bullish momentum acceleration.
• A crossing below zero may indicate bearish momentum acceleration.
• The smoothed nature of the WMA means the curve reacts slowly to price changes, making it suitable for identifying long-term trend reversals.

Implementation notes

• The Roc and Wma algorithms handle NaN internally; the indicator will only produce valid values after enough bars have passed for all calculations.
• MutSeriesF is used to create a series from the sum of the two ROC values for the WMA input.
• The indicator does not repaint because it uses only current bar values (index [0]) from the algorithms.
• All three parameters must be at least 1; using very small values may produce noisy output.

FAQ

What are the default parameter values and what do they mean?

Default WMA Length is 10, Long RoC Length is 14, Short RoC Length is 11. These are typical settings for a medium-term momentum oscillator.

How should I interpret the zero line crossings?

Crossing above zero suggests that the combined short and long-term momentum is turning positive, potentially indicating a bullish trend. Crossing below zero suggests the opposite.

Can I use this indicator as a standalone entry signal?

The Coppock Curve is a lagging, smoothed oscillator. It is best used in conjunction with other analysis (e.g., trend confirmation, volume) rather than as a sole entry signal.

Full source code

Indie Script v5, the built-in indicator as shipped with TakeProfit. Add it from the indicators menu or copy the code into the platform’s script editor.

# indie:lang_version = 5
from indie import indicator, param, plot, color, MutSeriesF
from indie.algorithms import Roc, Wma


@indicator('Coppock')  # Coppock Curve
@param.int('wma_length', default=10, min=1, title='WMA Length')
@param.int('long_roc_length', default=14, min=1, title='Long RoC Length')
@param.int('short_roc_length', default=11, min=1, title='Short RoC Length')
@plot.line(color=color.BLUE)
def Main(self, wma_length, long_roc_length, short_roc_length):
    l_roc = Roc.new(self.close, long_roc_length)[0]
    s_roc = Roc.new(self.close, short_roc_length)[0]
    curve = Wma.new(MutSeriesF.new(l_roc + s_roc), wma_length)[0]
    return curve