lattice::latticeParseFormula(x, data = data) 中的错误：模型必须是公式对象

Question

我尝试使用 rChart 的 rNVD3 包的离散条形图而不是相同的旧 ggplot2。但它需要一些公式参数作为第一个参数。我没有用过 lattice 包，我不知道如何创建一个。

这是我的数据框：

   df <- data.frame(
      Pupil = factor(c("Richy","Shyam","Nithin"), levels=c("Richy","Shyam","Nithin")), 
      Scores = c(75,93,62)
      )

我用来渲染情节的代码：

  require(rNVD3)
    bar1 <- nvd3Plot(x = "Pupil", y = "Scores", data = df, type = "discreteBarChart", width = 600)
    bar1$printChart("chart1")

错误是这样的：

Error in lattice::latticeParseFormula(x, data = data) : model must be a formula object

当我尝试纠正错误时：

 bar1<-nvd3Plot(Scores ~ Pupil, data = df, type = "discreteBarChart", width = 600)
    bar1$printChart("chart1")

它只显示了 .js 代码，但没有显示条形图。

<div id='chart1' class='nvd3Plot'></div>
    <script type='text/javascript'>
        drawchart1()
        function drawchart1(){  
          var opts = {"id":"chart1","yAxis":[],"x":"Pupil","y":"Scores","type":"discreteBarChart","width":600,"height":400},
            data = [{"Pupil":"Richy","Scores":75},{"Pupil":"Shyam","Scores":93},{"Pupil":"Nithin","Scores":62}]

          var data = d3.nest()
            .key(function(d){
              return opts.group === undefined ? 'main' : d[opts.group]
            })
            .entries(data)

          nv.addGraph(function() {
            var chart = nv.models[opts.type]()
              .x(function(d) { return d[opts.x] })
              .y(function(d) { return d[opts.y] })
              .width(opts.width)
              .height(opts.height)

           d3.select("#" + opts.id)
            .append('svg')
            .datum(data)
            .transition().duration(500)
            .call(chart);

           nv.utils.windowResize(chart.update);
           return chart;
          });
    };
</script>

Answer 1

rCharts 由于使用 reference classes. You are very close. First install rCharts. Then, instead of nvd3Plot, use nPlot as shown below. Also, you might be interested in htmlwidgets.

有时会有点混乱

library(rCharts)

df <- data.frame(
  Pupil = factor(c("Richy","Shyam","Nithin"), levels=c("Richy","Shyam","Nithin")), 
  Scores = c(75,93,62)
)

# without formula interface
nPlot(
  x = "Pupil", y = "Scores", data = df,
  type = "discreteBarChart", width = 600
)

# with formula interface
nPlot(Scores~Pupil, data = df, type = "discreteBarChart", width = 600)

lattice::latticeParseFormula(x, data = data) 中的错误：模型必须是公式对象

Error in lattice::latticeParseFormula(x, data = data) : model must be a formula object

r

rcharts