Question

我编写了一个使用d3.js读取csv文件的代码。我的csv文件是

x1，y1，x2，y2
  2.0000,0.0000，-4.0000,1.5000
  1.9800,0.0000，-3.9500,1.5000
  1.9600,0.0000，-3.9000,1.5000
  1.9400,0.0000，-3.8500,1.5000
  1.9200,0.0000，-3.8000,1.5000

我读取此文件的代码是

d3.csv("./data.csv", function(err, data){
    data1 = data.map(function(d) { return [ +d["x1"], +d["y1"] ]; });
    data2 = data.map(function(d) { return [ +d["x2"], +d["y2"] ]; });})

此代码读取csv文件并将其数据保存到数组，data1和data2中。

每个数组看起来像

data1 [0] [0] = 2.0000，data1 [0] [1] = 0.0000
  data1 [1] [0] = 1.9800，data1 [1] [1] = 0.0000
  data1 [2] [0] = 1.9600，data1 [2] [1] = 0.0000

现在，我想通过阅读json数据做同样的事情。我的json代码是

var inputdata = [
{"y2": "1.5000", "x2": "-4.0000","y1": "0.0000", "x1": "2.0000"},
{"y2": "1.5000", "x2": "-3.9500","y1": "0.0000", "x1": "1.9800"},
{"y2": "1.5000", "x2": "-3.9000","y1": "0.0000", "x1": "1.9600"},
{"y2": "1.5000", "x2": "-3.8500","y1": "0.0000", "x1": "1.9400"},
{"y2": "1.5000", "x2": "-3.8000","y1": "0.0000", "x1": "1.9200"},
];

然后我如何读取这个json代码并将数据放入数组data1和data2，如上面的csv代码？

Answer 1

您可以这样做：

var inputdata = [
{"y2": "1.5000", "x2": "-4.0000","y1": "0.0000", "x1": "2.0000"},
{"y2": "1.5000", "x2": "-3.9500","y1": "0.0000", "x1": "1.9800"},
{"y2": "1.5000", "x2": "-3.9000","y1": "0.0000", "x1": "1.9600"},
{"y2": "1.5000", "x2": "-3.8500","y1": "0.0000", "x1": "1.9400"},
{"y2": "1.5000", "x2": "-3.8000","y1": "0.0000", "x1": "1.9200"},
];
    data1 = inputdata.map(function(d) { return [ +d["x1"], +d["y1"] ]; });
    data2 = inputdata.map(function(d) { return [ +d["x2"], +d["y2"] ]; });
//do your task with data1 and data2

使用d3.js读取json文件

1 个答案: