R | Echarts | gauge undocumented

gauge.colors

# Undocumented feature found for 'gauge' in ECharts (https://echarts.apache.org/en/option.html#series-gauge.type)
# Attribute 'encode' is not even mentioned in the docs, but could be used when 'dataset' is present.
# All columns listed in 'encode' (like x,y,z) are ignored and first remaining dataset column becomes gauge data.
# In example below this 'first remaining' column is 'circumference'. Neat!?

library(echarty); library(dplyr)
df <-  Orange %>% filter(age==1582) %>% mutate(Tree=as.character(Tree))
clr <- c("#eeb422","#382278","#d9534f",'magenta','red')

p <- df %>% group_by(Tree) %>% ec.init( preset=FALSE,
   tl.series = list(
     type='gauge', axisLine=list(lineStyle=list(width=15)),
     max = 300,    # or max(df$circumference),
     encode=list(x='Tree', y='age')
))
i <- 0  # set series colors in options generated
p$x$opts$options <- lapply(p$x$opts$options, function(x) { 
   i <<- i+1
   x$series[[1]]$axisLine$lineStyle$color <- list(
    c(0.25, 'green'), 
    c(1, clr[i])); x })
p 

idea from @rdatasculptor