Technical indicator โ
This document introduces the built-in technical indicators in the chart and how to customize a technical indicator.
Built-in technical indicators โ
| Name | Default calc params | Name | Default calc params | Name | Default calc params |
|---|---|---|---|---|---|
| MA | [5, 10, 30, 60] | BIAS | [6, 12, 24] | VR | [24, 30] |
| EMA | [6, 12, 20] | BRAR | [26] | WR | [6, 10, 14] |
| SMA | [12, 2] | CCI | [13] | MTM | [6, 10] |
| BBI | [3, 6, 12, 24] | DMI | [14, 6] | EMV | [14, 9] |
| VOL | [5, 10, 20] | CR | [26, 10, 20, 40, 60] | SAR | [2, 2, 20] |
| MACD | [12, 26, 9] | PSY | [12, 6] | AO | [5, 34] |
| BOLL | [20, 2] | DMA | [10, 50, 10] | ROC | [12, 6] |
| KDJ | [9, 3, 3] | TRIX | [12, 20] | PVT | None |
| RSI | [6, 12, 24] | OBV | [30] | AVP | None |
Custom Technical Indicators โ
To create a custom technical indicator, you only need to generate a technical indicator information, and then add it globally through klinecharts.registerIndicator, add it to the chart and use it like the built-in technical indicator.
Attribute description โ
typescript
{
// indicator name
name: string
// The short name of the indicator, used for display, the name will be displayed by default
shortName?: string
// precision, default is 4
precision?: number
// calculation parameter
calcParams?: any[]
// Do you need ohlc
shouldOhlc?: boolean
// Do you need to format large data values, starting from 1000, for example, do you need to format 100K for 100000
shouldFormatBigNumber?: boolean
// Do you need visible
visible?: boolean
// z level
zLevel?: number
// extended data
extendData?: any
// series, default is 'normal'
series?: 'normal' | 'price' | 'volume'
// Data information
figures?: Array<{
// Used to get the median value of the calculation result
key: string
// for tooltip display
title?: string
// graphic type
type?: string
// Base value, if given, it will be drawn up and down with this value, generally used when the type is 'rect'
baseValue?: number
// is a method
attrs?: ({
data: IndicatorFigureAttrsCallbackData
coordinate: IndicatorFigureAttrsCallbackCoordinate
bounding: Bounding
barSpace: BarSpace
xAxis: XAxis
yAxis: YAxis
}) => IndicatorFigureAttrs
// is a method
styles?: (
data: {
// The data of the previous graph
prev: {
// k-line data, type refer to [data source]
kLineData?: KLineData,
// technical indicator data
indicatorData?: any
},
// data of the current graph
current: {
kLineData?: KLineData
indicatorData?: any
},
// Data for the next graph
next: {
kLineData?: KLineData,
indicatorData?: any
}
},
// technical chart example
indicator: Indicator
// The default technical indicator style, that is, the technical indicator style set globally, refer to the indicator in [Style]
defaultStyles: IndicatorStyle
) => IndicatorFigureStyle
}>,
// The specified minimum value, default null
minValue?: number
// The specified maximum value, default null
maxValue?: number
// style, support increment, default is null, type refer to indicator in [style]
styles?: IndicatorStyle
// calculation method, can be a promise
calc: (
// data source, see [data source] for type
dataList: KLineData[],
// technical indicator example
indicator: indicator
) => Promise<Array<any>> | Array<any>
// Regenerate figure graphic configuration method, which will be triggered after the calculation parameters change, refer to figures for the return type, the default is null
regenerateFigures?: (
// calculation parameter
calcParms: any[]
) => Array<IndicatorFigure<D>>
// Create a custom hint text
createTooltipDataSource?: (params: {
// data source, see [data source] for type
kLineDataList: KLineData[]
// technical indicator example
indicator: Indicator
// Visible area information
visibleRange: {
// start data index
from: number
// end data index
to: number
// real start data index
realFrom: number
// real end data index
realTo: number
},
// window size information
bounding: {
// width
width: number
// high
height: number
// distance to the left
left: number
// distance to the right
right: number
// distance from top
top: number
// distance from bottom
bottom: number
},
// Information about the cross cursor
crosshair: {
// The window id where the cross point of the cross cursor is located
paneId?: string
// real x coordinate
realX?: number
// k-line data, type refer to [data source]
kLineData?: KLineData
// data index
dataIndex?: number
// real data index
realDataIndex?: number
},
// The default technical indicator style, that is, the technical indicator style set globally, refer to the indicator in [Style]
defaultStyles: IndicatorStyle
// x-axis component, some built-in conversion methods
xAxis: XAxis
// y-axis component, with some built-in conversion methods
yAxis: YAxis
}) => ({
// name
name?: string
// Calculate the parameter text, if name has no value, it will not be displayed
calcParamsText?: string
// value information
values?: Array<{
title: string | {
text: string
color: string
}
value: string | {
text: string
color: string
}
}>
}),
// Custom drawing, if true is returned, the graphics configured by figures will not be drawn
draw?: (params: {
// canvas context
ctx: CanvasRenderingContext2D
// data source, see [data source] for type
kLineDataList: KLineData[]
// technical indicator example
indicator: Indicator
// Visible area information
visibleRange: {
// start data index
from: number
// endpoint data index
to: number
},
// window size information
bounding: {
// width
width: number
// high
height: number
// distance to the left
left: number
// distance to the right
right: number
// distance from top
top: number
// distance from bottom
bottom: number
},
// information about the size of the candlestick
barSpace: {
// candlestick size
bar: number
halfBar: number
// candlesticks do not include dimensions of gaps between candlesticks
gapBar: number
halfGapBar: number
},
// The default technical indicator style, that is, the technical indicator style set globally, refer to the indicator in [Style]
defaultStyles: IndicatorStyle
// x-axis component, some built-in conversion methods
xAxis: XAxis
// y-axis component, with some built-in conversion methods
yAxis: YAxis
}) => boolean
}Step.1 โ
First determine the calculation parameters (calcParams) and configuration items (figures). The 'MA' technical indicator needs to display the line connecting the average closing price of the two periods, one is 'ma1' and the other is 'ma2'. So figures are configured as:
javascript
{
// The calculation parameters are 2, one calculates the mean value of 5 cycle times, namely 'ma1', and the other calculates the mean value of 10 cycle times, namely 'ma10'
calcParams: [5, 10],
figures: [
// first line 'ma5'
{ key: 'ma1', title: 'MA5: ', type: 'line' },
// second line 'ma10'
{ key: 'ma2', title: 'MA10: ', type: 'line' }
]
}Step.2 โ
Determine other attributes
javascript
{
name: 'MA',
shortName: 'MA',
calcParams: [5, 10],
figures: [
{ key: 'ma1', title: 'MA5: ', type: 'line' },
{ key: 'ma2', title: 'MA10: ', type: 'line' }
],
// When the calculation parameters are changed, it is hoped that the prompt is the same as the parameters, that is, the value of title needs to be changed
regenerateFigures: (params) => {
return params. map((p, i) => {
return { key: `ma${i + 1}`, title: `MA${p}: `, type: 'line' }
})
},
// Calculation results
calc: (kLineDataList, { calcParams, figures }) => {
// Note: The number of returned data needs to be consistent with the number of data in kLineDataList. If there is no value, replace it with {}.
// It is best to take the callback parameter calcParams as the calculation parameter. If not, when the subsequent calculation parameters change, the calculation here cannot respond in time
const closeSums = []
return kLineDataList. map((kLineData, i) => {
const ma = {}
const close = kLineData. close
calcParams.forEach((param, j) => {
closeSums[j] = (closeSums[j] || 0) + close
if (i >= param - 1) {
ma[figures[j].key] = closeSums[j] / param
closeSums[j] -= kLineDataList[i - (param - 1)].close
}
})
// If there is a value, the data format of each item here should be { ma1: xxx, ma2: xxx }
// Each key needs to be consistent with the value corresponding to the subkey in figures
return ma
})
}
}So a custom indicator is completed.