d3.js pie.sortValues()用法及代碼示例

D3，js中的pie.sortValues()函數用於將值比較器設置為給定函數。當未指定比較器函數時，它將返回當前值比較器，默認為降序。

值和數據比較器之間的區別在於，兩個參數a和b是使用值訪問器從數據數組派生的值。如果b的弧必須在b的弧之前，則比較器函數必須返回一個大於0的值。

用法:

pie.sortValues( compare(a, b) )

參數：該函數接受如上所述和以下描述的單個參數：

comparator:它具有一個比較器函數，該函數比較兩個參數a和b，在此基礎上將進行排序。它是一個可選參數。

返回值：該函數返回當前值比較器。

下麵的示例說明了D3.js中的pie.sortValues()函數：

範例1：

HTML

<!DOCTYPE html> 
<html> 
  
<head> 
    <script src="https://d3js.org/d3.v6.min.js"> 
    </script> 
</head> 
  
<body> 
    <div style="width:300px; 
              height:300px;"> 
        <center> 
            <h1 style="color:green"> 
                GeeksforGeeks 
            </h1> 
            <h2> 
                pie.sortValues() 
            </h2> 
        </center> 
        <svg width="300" height="250"> 
        </svg> 
        <button>Click Me</button> 
    </div> 
    <script> 
        // Data to be added in the pie chart 
        var data = [ 
            { "property":"fp5", "value":5 }, 
            { "property":"gp5", "value":16 }, 
            { "property":"bp4", "value":10 }, 
            { "property":"ap3", "value":12 }, 
            { "property":"mp2", "value":19 }, 
            { "property":"kp1", "value":21 }, 
        ] 
  
        // Selecting SVG using d3.select() 
        var svg = d3.select("svg"); 
  
        // Creating Pie generator 
        var pie = d3.pie() 
            // Use of pie.value() Function 
            .value((d) => { return d.value }) 
            (data); 
  
        function updatePie() { 
  
            // Creating Pie generator 
            var pie = 0 
            var pie = d3.pie() 
                .value((d) => { return d.value }) 
  
                // Use of pie.sortValues() Function 
                .sortValues(function (a, b) { 
                    return a - b; 
                }) 
                (data); 
            // Creating arc 
            var arc = d3.arc() 
                .innerRadius(0) 
                .outerRadius(100); 
  
            let g = svg.append("g") 
                .attr("transform", "translate(150,120)"); 
  
            // Grouping different arcs 
            var arcs = g.selectAll("arc") 
                .data(pie) 
                .enter() 
                .append("g"); 
  
            // Appending path  
            arcs.append("path") 
                .attr("fill", (data, i) => { 
                    return d3.schemeSet2[i]; 
                }) 
                .attr("d", arc); 
  
            arcs.append("text") 
                .attr("transform", (d) => { 
                    return "translate(" + 
                        arc.centroid(d) + ")"; 
                }) 
                .text(function (d) { 
                    return d.value; 
                }); 
        } 
        let btn = document.querySelector("button") 
        btn.addEventListener("click", updatePie); 
  
        // Creating arc 
        var arc = d3.arc() 
            .innerRadius(0) 
            .outerRadius(100); 
  
        let g = svg.append("g") 
            .attr("transform", "translate(150,120)"); 
  
        // Grouping different arcs 
        var arcs = g.selectAll("arc") 
            .data(pie) 
            .enter() 
            .append("g"); 
  
        // Appending path  
        arcs.append("path") 
            .attr("fill", (data, i) => { 
                return d3.schemeSet2[i]; 
            }) 
            .attr("d", arc); 
  
        arcs.append("text") 
            .attr("transform", (d) => { 
                return "translate(" + 
                    arc.centroid(d) + ")"; 
            }) 
            .text(function (d) { 
                return d.value; 
            }); 
    </script> 
</body> 
  
</html>

輸出：

在單擊按鈕之前：

單擊按鈕後：

範例2：

HTML

<!DOCTYPE html> 
<html> 
  
<head> 
    <script src="https://d3js.org/d3.v6.min.js"> 
    </script> 
</head> 
  
<body> 
    <div style="width:300px;  
              height:300px;"> 
        <center> 
            <h1 style="color:green"> 
                GeeksforGeeks 
            </h1> 
            <h2> 
                pie.sortValues(); 
            </h2> 
        </center> 
        <svg width="300" height="250"> 
        </svg> 
        <button>Clickme</button> 
    </div> 
    <script> 
        // Data to be added in the pie chart 
        var data = [ 
            { "property":"fp5", "value":"5" }, 
            { "property":"gp5", "value":"6" }, 
            { "property":"bp4", "value":"b" }, 
            { "property":"ap3", "value":"a" }, 
            { "property":"mp2", "value":9 }, 
            { "property":"kp1", "value":"8" }, 
        ] 
  
        // Selecting SVG using d3.select() 
        var svg = d3.select("svg"); 
  
        // Creating Pie generator 
        var pie = d3.pie() 
            // Use of pie.value() Function 
            .value((d) => { return d.value }) 
            (data); 
  
        function updatePie() { 
            // Creating Pie generator 
            var pie = 0 
            var pie = d3.pie() 
                .value((d) => { return d.value }) 
  
                // Use of pie.sortValues() Function 
                .sortValues(function (b, a) { 
                    console.log("a:" + a + ", 
                      b:" + b + ", 
                        a - b:", b - a); 
          return b - a; 
                }) 
                (data); 
            // Creating arc 
            var arc = d3.arc() 
                .innerRadius(30) 
                .outerRadius(80); 
  
            let g = svg.append("g") 
                .attr("transform", "translate(150,120)"); 
  
            // Grouping different arcs 
            var arcs = g.selectAll("arc") 
                .data(pie) 
                .enter() 
                .append("g"); 
  
            // Appending path  
            arcs.append("path") 
                .attr("fill", (data, i) => { 
                    return d3.schemeSet1[i]; 
                }) 
                .attr("d", arc); 
  
            arcs.append("text") 
                .attr("transform", (d) => { 
                    return "translate(" + 
                        arc.centroid(d) + ")"; 
                }) 
                .text(function (d) { 
                    return d.value; 
                }); 
        } 
        let btn = document.querySelector("button") 
        btn.addEventListener("click", updatePie); 
        // Creating arc 
        var arc = d3.arc() 
            .innerRadius(30) 
            .outerRadius(80); 
  
        let g = svg.append("g") 
            .attr("transform", "translate(150,120)"); 
  
        // Grouping different arcs 
        var arcs = g.selectAll("arc") 
            .data(pie) 
            .enter() 
            .append("g"); 
  
        // Appending path  
        arcs.append("path") 
            .attr("fill", (data, i) => { 
                return d3.schemeSet1[i]; 
            }) 
            .attr("d", arc); 
  
        arcs.append("text") 
            .attr("transform", (d) => { 
                return "translate(" + 
                    arc.centroid(d) + ")"; 
            }) 
            .text(function (d) { 
                return d.value; 
            }); 
    </script> 
</body> 
  
</html>

輸出：

在單擊按鈕之前：

單擊按鈕後：

相關用法

注：本文由純淨天空篩選整理自tarun007大神的英文原創作品 D3.js pie.sortValues() Function。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。