使用d3从内存中逐列读取数据

时间:2014-04-08 15:48:03

标签: javascript parsing d3.js

我有正在保存到内存中的数据。我正在寻找一种方法来绘制保存到内存中的数据。以下是阅读和尝试绘制文件图形的示例脚本。

function Read() {
  var myfile=document.getElementById("csvFileInput");
  handleFiles(myfile);
}

function handleFiles(myfile) {
// Check for the various File API support.
if (window.FileReader) {
    // FileReader are supported.
    var files = myfile.files[0];
    getAsText(files);
} else {
    alert('FileReader are not supported in this browser.');
}
}

 function getAsText(files) {
var reader = new FileReader();
// Read file into memory as UTF-8      
reader.readAsText(files);
// Handle errors load
reader.onload = loadHandler;
reader.onerror = errorHandler;
}
   function loadHandler(event) {
    var csv = event.target.result;
    processData(csv);
 }

   processData(csv) {
  var allTextLines = csv.split(/\r\n|\n/);
  var lines = [];
  for (var i=0; i<allTextLines.length; i++) {
      var data = allTextLines[i].split(',');
          var tarr = [];
          for (var j=0; j<data.length; j++) {
              tarr.push(data[j]);
          }
          lines.push(tarr);
  }
console.log(lines);
alert("graphing");      
  Graph(allTextLines);
}

function errorHandler(evt) {
 if(evt.target.error.name == "NotReadableError") {
     alert("Cannot read file !");
   }
   }  
function Graph(files) {

var x = d3.scale.linear()
  .range([0, width]);

var y = d3.scale.linear()
  .range([height, 0]);

var xAxis = d3.svg.axis()
  .scale(x)
  .orient("bottom");

var yAxis = d3.svg.axis()
  .scale(y)
  .orient("left");

var line1 = d3.svg.line()
  .x(function(d) { return x(d.date); })
  .y(function(d) { return y(d.A); });

var line2 = d3.svg.line()
  .x(function(d) { return x(d.date); })
  .y(function(d) { return y(d.B); });

var svg1 = d3.select("#ecgplot").append("svg")
  .attr("width", width + margin.left + margin.right)
  .attr("height", height + margin.top + margin.bottom)
 .append("g")
  .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

 var data = files;

 data.forEach(function(d) {
   d.date = +d.tm;
   d.A = +d.Adata;
  d.B = +d.Bdata;
 });

 x.domain(d3.extent(data, function(d) { return d.date; }));
 y.domain(d3.extent(data, function(d) { return d.A; }));

 svg1.append("g")
      .attr("class", "x axis")
      .attr("transform", "translate(0," + height + ")")
      .call(xAxis)
     .append("text")
      .attr("transform", "rotate(0)")
      .attr("y", 28)
      .attr("x", 450)
      .attr("dx", ".71em")
     .style("text-anchor", "end")
     .text("Time (in second)");
   svg1.append("g")
     .attr("class", "y axis")
     .call(yAxis)
     .append("text")
     .attr("transform", "rotate(-90)")
     .attr("y", -35)
     .attr("x", -35)
     .attr("dy", ".71em")
     .style("text-anchor", "end")
      .text("A");
}

这是我在显示时保存到内存中的数据。

"tm","Adata","Bdata",0,-0.14,4.781,0.003,-0.153,4.781,0.006,-0.151,4.831,0.008,-0.137,4.831

我认为通过将数据保存到内存的方式,我必须将数据解析为5行3列,但我不确定如何执行此操作然后将数据读入d3可以注册。

0 个答案:

没有答案