Initialize command — ec.init • echarty

Required to build a chart. In most cases this will be the only command necessary.

Usage

ec.init(
  df = NULL,
  preset = TRUE,
  ctype = "scatter",
  ...,
  series.param = NULL,
  tl.series = NULL,
  width = NULL,
  height = NULL
)

Arguments

df: Optional data.frame to be preset as dataset, default NULL
By default the first column is for X values, second column is for Y, and third is for Z when in 3D.
Best practice is to have the grouping column placed last. Grouping column cannot be used as axis.
Timeline requires a grouped data.frame to build its options.
If grouping is on multiple columns, only the first one is used to determine settings.
preset: Boolean (default TRUE). Build preset attributes like dataset, series, xAxis, yAxis, etc.
When preset is FALSE, these attributes need to be set explicitly.
ctype: Chart type, default is 'scatter'. Could be set in series.param instead.
...: Optional widget attributes. See Details.
series.param: Additional attributes for single preset series, default is NULL.
Defines a single series for both non-timeline and timeline charts.
Multiple series should be defined directly with series=list(list(type=...),list(type=...)) or added with ec.upd.
tl.series: Deprecated, use timeline and series.param instead.
width, height: Optional valid CSS unit (like '100%', '500px', 'auto') or a number, which will be coerced to a string and have 'px' appended.

Value

A widget to plot, or to save and expand with more features.

Details

Command ec.init creates a widget with createWidget, then adds some ECharts features to it.
Numerical indexes for series,visualMap,etc. are R-counted (1,2...)

Presets:
When data.frame df is present, a dataset is preset.
When df is grouped and ctype is not NULL, more datasets with legend and series are also preset.
Plugin '3D' (load='3D') is required for GL series like scatterGL, linesGL, etc.
Plugins 'leaflet' and 'world' preset center to the mean of all coordinates from df.
Users can delete or overwrite any presets as needed.

Widget attributes:
Optional echarty widget attributes include:

elementId - Id of the widget, default is NULL(auto-generated)
load - name(s) of plugin(s) to load. A character vector or comma-delimited string. default NULL.
ask - prompt user before downloading plugins when load is present, FALSE by default
js - single string or a vector with JavaScript expressions to evaluate.
single: exposed chart object (most common)
vector: see code in examples
First expression evaluated before initialization, exposed object window
Second is evaluated with exposed object opts.
Third is evaluated with exposed chart object after opts set.
renderer - 'canvas'(default) or 'svg'
locale - 'EN'(default) or 'ZH'. Use predefined or custom like so.
useDirtyRect - enable dirty rectangle rendering or not, FALSE by default, see here

Built-in plugins:

leaflet - Leaflet maps with customizable tiles, see source
world - world map with country boundaries, see source
lottie - support for lotties
ecStat - statistical tools, seeecharts-stat
custom - renderers for ecr.band and ecr.ebars
Plugins with one-time installation:
3D - support for 3D charts and WebGL acceleration, see source and docs
This plugin is auto-loaded when 3D/GL axes/series are detected.
liquid - liquid fill, see source
gmodular - graph modularity, see source
wordcloud - cloud of words, see source
or install your own third-party plugins.

Crosstalk:
Parameter df should be of type SharedData, see more info.
Optional parameter xtKey: unique ID column name of data frame df. Must be same as key parameter used in SharedData$new(). If missing, a new column XkeyX will be appended to df.
Enabling crosstalk will also generate an additional dataset called Xtalk and bind the first series to it.

Timeline:
Defined by series.param for the options series and a timeline list for the actual control. A grouped df is required, each group providing data for one option serie. Timeline data and options will be preset for the chart.
Each option title can include the current timeline item by adding a placeholder '%@' in title$text. See example below.
Another preset is encode(x=1,y=2,z=3), which are the first 3 columns of df. Parameter z is ignored in 2D. See Details below.
Optional attribute groupBy, a df column name, can create series groups inside each timeline option.
Options/timeline for hierarchical charts like graph,tree,treemap,sankey have to be built directly, see example.

Encode
A series attribute to define which columns to use for the axes, depending on chart type and coordinate system:

set x and y for coordinateSystem cartesian2d
set lng and lat for coordinateSystem geo and scatter series
set value and name for coordinateSystem geo and map series
set radius and angle for coordinateSystem polar
set value and itemName for pie chart Example: encode(x='col3', y='col1') binds xAxis to df column 'col3'.

Examples

 # basic scatter chart from a data.frame, using presets
cars |> ec.init()

 
 # grouping, tooltips, formatting
iris |> dplyr::group_by(Species) |> 
ec.init(        # init with presets
  tooltip= list(show= TRUE),
  series.param= list( 
    symbolSize= ec.clmn('Petal.Width', scale=7),
    tooltip= list(formatter= ec.clmn('Petal.Width: %@', 'Petal.Width'))
  )
)


data.frame(n=1:5) |> dplyr::group_by(n) |> ec.init(
  title= list(text= "gauge #%@"),
  timeline= list(show=TRUE, autoPlay=TRUE),
  series.param= list(type='gauge', max=5)
)