Documentation
Still have questions?
Contact support
Still have questions?
Contact support

# Fibonacci Arc

## Overview

The Fibonacci Arc annotation allows to add a Fibonacci arc to a chart.

This article explains how to add a Fibonacci Arc and configure its basic and visual settings. You can find more settings and other useful information in the articles describing annotations in general:

## Basic Settings

To add a Fibonacci Arc annotation to a chart, call the fibonacciArc() method of the annotations() object.

Next, use the xAnchor(), valueAnchor(), secondXAnchor(), and secondValueAnchor() methods to set 2 points that determine the position of the Fibonacci arc. Usually, the most convenient way to do this is object notation:

``````// create a stock chart
chart = anychart.stock();

// create a plot on the chart
var plot = chart.plot(0);

// access the annotations() object of the plot to work with annotations
var controller = plot.annotations();

// create a Fibonacci Arc annotation
controller.fibonacciArc({
xAnchor: "2006-07-30",
valueAnchor: 17.24,
secondXAnchor: "2007-01-07",
secondValueAnchor: 28.92
});
``````

This is how it looks like:

## Configuring Levels

You can set the levels of a Fibonacci Arc annotation by using the levels() method and passing an array of values as a parameter:

``````// create a Fibonacci Arc annotation
controller.fibonacciArc({
xAnchor: "2006-07-30",
valueAnchor: 17.24,
secondXAnchor: "2007-01-07",
secondValueAnchor: 28.92,
levels: [0, 0.2, 0.4, 0.7, 1]
});
``````

## Visual Settings

You can also configure the visual settings of a Fibonacci Arc annotation:

In the sample below, there are two Fibonacci Arc annotations with some of the visual settings configured (by using an object in the first case and methods in the second):

``````// create the first Fibonacci Arc annotation and configure its visual settings
fibonacciArc1 = controller.fibonacciArc({
xAnchor: "2006-07-30",
valueAnchor: 17.24,
secondXAnchor: "2007-01-07",
secondValueAnchor: 28.92,
hoverTrend: "2 #0000FF",
hoverStroke: "2 #FF0000",
selectTrend: "5 #0000FF",
selectStroke: "5 #FF0000"
});

// create the second Fibonacci Arc annotation
fibonacciArc2 = controller.fibonacciArc();

// set the position of the second annotation
fibonacciArc2.xAnchor("2004-01-11");
fibonacciArc2.valueAnchor(29.13);
fibonacciArc2.secondXAnchor("2004-08-08");
fibonacciArc2.secondValueAnchor(17.86);

// configure the visual settings of the second annotation
fibonacciArc2.stroke("#2196F3", 3, "10 2");
``````

To configure the visual settings of a certain level, use the stroke(), hoverStroke(), and selectStroke() methods with a function as a parameter. In this function, get level values from the context:

``````// create a Fibonacci Arc annotation
controller.fibonacciArc({
xAnchor: "2006-07-30",
valueAnchor: 17.24,
secondXAnchor: "2007-01-07",
secondValueAnchor: 28.92,
stroke: colorLevels,
hoverStroke: colorLevels,
selectStroke: colorLevels
});

function colorLevels(){
if (this.level!==undefined)
{
switch (this.level) {
case 0.5:
return "Red";
break;
case 0.618:
return {color: "Blue", dash: "2 2"};
break;
default:
return "Black"
}
}
};
``````