Understanding line.get_price() Function in Pine Script

The line.get_price() function in Pine Script is used to retrieve the price level of a graphical line at a specified bar index. It’s particularly useful for custom indicators or strategies that involve dynamic lines, such as trend lines or support/resistance levels. Let’s delve into its syntax, usage, and key features to understand how it can be leveraged in trading scripts.

Syntax

The syntax for line.get_price() is as follows:

line.get_price(id, x) → series float

Arguments

id (series line): This is the line object from which you want to get the price. The line must have been previously created in your script using functions like line.new().
x (series int): The bar index for which you want to obtain the price level of the line. This is an integer value that represents a specific bar on the chart.

Example

Here’s a practical example to illustrate how line.get_price() can be used within a Pine Script indicator:

//@version=5
indicator("DynamicPriceLevel", overlay=false)
var line trendLine = na
if bar_index == 10
    trendLine := line.new(0, high[5], bar_index, high)
plot(line.get_price(trendLine, bar_index), color=color.green)

In this example, a dynamic price level is calculated and plotted on the chart. The key steps are:

Initialization: A variable trendLine is declared to store the line object.
Line Creation: At the 10th bar index on the chart, a new line (trendLine) is created using line.new(). This line extends from the 0th bar to the current bar, with its price level based on the high price 5 bars ago and the current high price.
Plotting Price Level: The line.get_price() function is used to plot the price level of trendLine at each bar index. This is visualized on the chart in green.

Returns

The function returns the price value of the line id at the specified bar index x.

Remarks

The line is assumed to have been created with extend=extend.both, meaning it extends indefinitely to the left and right on the chart.
This function is applicable only to lines created with xloc.bar_index. Attempting to use it with lines created using xloc.bar_time will result in an error.

Key Features and Takeaways

Function Usability: line.get_price() is essential for scripts that require dynamic interaction with graphical lines, allowing for precise price level calculations at any given bar.
Syntax and Application: Understanding the syntax is crucial for effectively using this function in your trading scripts. The function’s ability to return a floating-point series makes it versatile for various trading strategies.
Limitations: The function’s application is limited to lines created with xloc.bar_index, emphasizing the importance of understanding Pine Script’s coordinate systems.

By incorporating line.get_price() into your Pine Script indicators or strategies, you can enhance their functionality and provide more dynamic analysis capabilities on TradingView charts.