r - R Shiny 中的渐变色数据表行

Question

在R的Shiny中，我可以做这样的东西吗 example ，但是负值在哪里被赋予不同的颜色，并使用它们的条形长度的绝对值来绘制？

# using styleColorBar
datatable(df) %>% formatStyle(names(df),
  background = styleColorBar(range(df), 'lightblue'),
  backgroundSize = '98% 88%',
  backgroundRepeat = 'no-repeat',
  backgroundPosition = 'center')

Answer 1

您可以使用rowCallback手动执行此操作

如你所见

sss=datatable(df) %>% formatStyle(names(df),
                              background = styleColorBar(range(df), 'lightblue'),
                              backgroundSize = '98% 88%',
                              backgroundRepeat = 'no-repeat',
                              backgroundPosition = 'center')


sss$x$options$rowCallback

为每列生成:

function(row, data) { var value=data[ 1]; if (value!==null) $(this.api().cell(row, 1).node()).css({'background':isNaN(parseFloat(value)) || value <= -1.311 ? '' : 'linear-gradient(90deg, transparent ' + (2.199 - value)/3.51 * 100 + '%, lightblue ' + (2.199 - value)/3.51 * 100 + '%)','background-size':'98% 88%','background-repeat':'no-repeat','background-position':'center'});

所以:

1)您需要计算范围变量:

rr=range(df)[2]-range(df)[1]
r1=range(df)[2]
r0=range(df)[1]

2)比在rowCallback中使用它

  datatable(
  df,  
  options = list(
        rowCallback=JS(paste0("function(row, data) {",
                              paste(lapply(1:ncol(df),function(i){
                                paste0("var value=data[",i,"];
                                       if (value!==null){
                                       if(value<0){
                                       $(this.api().cell(row,",i,").node()).css({'background':isNaN(parseFloat(value)) || value <=",r0," ? '' : 'linear-gradient(90deg, transparent ' + (",r1," - value)/",rr," * 100 + '%, red ' + (",r1," - value)/",rr," * 100 + '%)','background-size':'98% 88%','background-repeat':'no-repeat','background-position':'center'});
                                       }else{
                                       $(this.api().cell(row,",i,").node()).css({'background':isNaN(parseFloat(value)) || value <=",r0," ? '' : 'linear-gradient(90deg, transparent ' + (",r1," - value)/",rr," * 100 + '%, lightblue ' + (",r1," - value)/",rr," * 100 + '%)','background-size':'98% 88%','background-repeat':'no-repeat','background-position':'center'});
                                       }
                                       } ") 
}),collapse="\n"),
"}"))
  )
) 

这里我硬编码了颜色(红色和浅蓝色)

结果

如果你想要不同的正负长度，你需要不同的范围变量或使用 abs\Math.abs - 绝对值(对于 JS 中的 var 和范围)

附注

JS 中列的计数从 0 开始，因此如果您没有行名，则需要 lapply 中的 0:(ncol(df)-1) 才能获得正确的结果

更新

绝对值的范围 -1 :1 和色标

df = as.data.frame(cbind(matrix(round(runif(50, -1, 1), 3), 10), sample(0:1, 10, TRUE)))


rr=range(abs(df))[2]-range(abs(df))[1]
r1=range(abs(df))[2]
r0=range(abs(df))[1]



datatable(
  df,  
  options = list(
        rowCallback=JS(paste0("function(row, data) {",
                              paste(lapply(1:ncol(df),function(i){
                                paste0("var value=Math.abs(data[",i,"]);
                                        var value2=data[",i,"];
                                       if (value!==null){
                                       if(value2<0){
                                       $(this.api().cell(row,",i,").node()).css({'background':isNaN(parseFloat(value)) || value <=",r0," ? '' : 'linear-gradient(90deg, transparent ' + (",r1," - value)/",rr," * 100 + '%, red ' + (",r1," - value)/",rr," * 100 + '%)','background-size':'98% 88%','background-repeat':'no-repeat','background-position':'center'});
                                       }else{
                                       $(this.api().cell(row,",i,").node()).css({'background':isNaN(parseFloat(value)) || value <=",r0," ? '' : 'linear-gradient(90deg, transparent ' + (",r1," - value)/",rr," * 100 + '%, lightblue ' + (",r1," - value)/",rr," * 100 + '%)','background-size':'98% 88%','background-repeat':'no-repeat','background-position':'center'});
                                       }
                                       } ") 
}),collapse="\n"),
"}"))
  )
)