Chart.js点格式的散点图数据

Question

Chart.js散点图仅接受点格式（x，y）的数据。我试图从名为meds.json的文件中用药物信息填充数据点更具体地说，x是药物的最后填充日期的月份，y是剂量。

我如何从meds.json文件中获取所有这些数据并将其插入到数据中以创建散点图的点？如果我尝试获取所有日期并将其存储在一个数组中，并将所有剂量值存储在另一个数组中，那么如何使用这些日期填充点数据？

这是使用Chart.js制作散点图的方法，我正在尝试填充数据'data'下的x，y点：

// charts.js
var scatterChart = new Chart(ctx, {
        type: 'scatter',
        data: {
            datasets: [{
                label: 'Scatter Dataset',
                data: [{
                    // x = month, y = dose
                    // fill these in for all meds in the json file
                    x: -10,
                    y: 0
                }, {
                    x: 0,
                    y: 10
                }, {
                    x: 10,
                    y: 5
                }]
            }]
        },
        options: {
            scales: {
                xAxes: [{
                    type: 'linear',
                    position: 'top'
                }]
            }
        }
    });
}

meds.json

[
  {
    "name": "Simvastatin",
    "dose": 10,
    "dose unit": "mg",
    "freq": "qd",
    "route": "PO",
    "last fill date": "2/15/2020",
    "coverage": "100%",
    "anticipated remaining fills": 2
  },
  {
    "name": "Lisinopril",
    "dose": 5,
    "dose unit": "mg",
    "freq": "qd",
    "route": "PO",
    "last fill date": "2/15/2020",
    "coverage": "100%",
    "anticipated remaining fills": 2
  }  

    ...... The list goes on

]

Answer 1

您实际上应该为此使用折线图，它会更合适，并准确显示一个月与剂量之间的关系。

但是由于您要求散点图...您可以这样做：

const data = [{
    "name": "Simvastatin",
    "dose": 10,
    "dose unit": "mg",
    "freq": "qd",
    "route": "PO",
    "last fill date": "2/15/2020",
    "coverage": "100%",
    "anticipated remaining fills": 2
  },
  {
    "name": "Lisinopril",
    "dose": 5,
    "dose unit": "mg",
    "freq": "qd",
    "route": "PO",
    "last fill date": "2/15/2020",
    "coverage": "100%",
    "anticipated remaining fills": 2
  }
]

const transformedData = data.map(obj=>{
  return {
    x:new Date(obj["last fill date"]).getMonth() + 1,
    y:obj.dose,
  }
})

console.log(transformedData)

然后用作

var scatterChart = new Chart(ctx, {
        type: 'scatter',
        data: {
            datasets: [{
                label: 'Scatter Dataset',
                data: transformedData
            }]
        },
        options: {
            scales: {
                xAxes: [{
                    type: 'linear',
                    position: 'top'
                }]
            }
        }
    });
}

希望这会有所帮助！