d3.js voronoi.extent()用法及代碼示例

voronoi.extent()函數用於設置Voronoi生成器函數的範圍。給定的範圍值用於在給定的邊界內設置Voronoi布局的裁剪範圍。邊界以二維數組形式給出，看起來像[[x0，y0]，[x1，y1]]。如果未指定範圍，則它將返回其默認值為null的當前剪輯範圍。

用法:

d3.voronoi().extent([extent]);

參數：此函數采用上麵給出的和下麵描述的一個參數。

extent:它告知要修剪的區域。它采用二維數組形式的值。

返回值：此函數不返回任何內容。

注意：請創建一個“data.csv”文件。該文件的數據在下麵的代碼中給出。

下麵給出了Voronoi.extent()函數的一些示例。

範例1：

HTML

<!DOCTYPE html>  
<html lang="en">  
  
<head>  
    <meta charset="UTF-8">  
    <meta name="viewport" content="  
        width=device-width, initial-scale=1.0">  
  
    <script type="text/javascript"
        src="https://d3js.org/d3.v4.min.js">  
    </script> 
    <script src="https://d3js.org/d3-voronoi.v1.min.js"> 
    </script> 
</head>  
  
<body>  
    <h1 style="color:green">GeeksforGeeks</h1> 
    <h3 style="color:green">voronoi.extent()</h3> 
      
    <script>  
        d3.csv("data.csv", function(error, data){ 
            var svg = d3.select("body") 
                        .append("svg") 
                        .attr("height", 400) 
                        .attr("width", 400) 
                        .append("g") 
                        .attr("transform",  
                     "translate(" + 20 + ", " + -20 + ")"); 
  
            var y = d3.scaleLinear() 
                      .domain([2, 20]) 
                      .range([400, 0]); 
            var x = d3.scaleLinear() 
                      .domain([2, 15]) 
                      .range([0, 400]); 
            svg.append("g") 
                    .call(d3.axisLeft(y)); 
  
            svg.append("g") 
                    .attr("transform",  
                     "translate(0, " + 400 + ")") 
                    .call(d3.axisBottom(x)); 
            var voronoi = d3.voronoi() 
                        .x(function(d) { return x(d.x); }); 
                  voronoi.y(function(d) { return y(d.y); }) 
                // Setting the extent using voronoi.extent()  
                .extent([[50, 50], [300, 300]]); 
                      
            svg.append("g").selectAll("path") 
                .data(voronoi(data).polygons()) 
                .enter() 
                .append("path") 
                .attr("d", (d)=>{ return d ?  
                ("M" + d.join("L") + "Z"):null; }) 
                .attr("fill", "none") 
                .attr("stroke", "black"); 
        }); 
  
        // Data for CSV file 
        // x, y, group 
        // 45, 4.4, H 
        // 9.1, 4.4, H 
        // 9.9, 9.9, H 
        // 4.45, 9.6, H 
        // 4, 7.6, H 
        // 9, 45, H 
        // 4, 9.7, H 
        // 9.7, 4.7, H 
        // 9.9, 4.5, H 
        // 4, 4.5, H 
        // 7.9, 9, H 
        // 9.9, 45, H 
        // 9, 4.4, H 
    </script>  
</body> 
</html>

輸出：

範例2：

HTML

<!DOCTYPE html>  
<html lang="en">  
  
<head>  
    <meta charset="UTF-8">  
    <meta name="viewport" content="  
        width=device-width, initial-scale=1.0">  
  
    <script type="text/javascript"
        src="https://d3js.org/d3.v4.min.js">  
    </script> 
    <script src="https://d3js.org/d3-voronoi.v1.min.js"> 
    </script> 
</head>  
  
<body>  
    <h1 style="color:green">GeeksforGeeks</h1> 
    <h3 style="color:green">voronoi.extent()</h3> 
      
    <script>  
        d3.csv("data.csv", function(error, data){ 
            var svg = d3.select("body") 
                        .append("svg") 
                        .attr("height", 400) 
                        .attr("width", 400) 
                        .append("g") 
                        .attr("transform", "translate 
                        (" + 20 + ", " + -20 + ")"); 
  
            var y = d3.scaleLinear() 
                      .domain([2, 20]) 
                      .range([400, 0]); 
            var x = d3.scaleLinear() 
                      .domain([2, 15]) 
                      .range([0, 400]); 
            svg.append("g") 
                    .call(d3.axisLeft(y)); 
  
            svg.append("g") 
                    .attr("transform", "translate(0, " + 400 + ")") 
                    .call(d3.axisBottom(x)); 
  
  
            var voronoi = d3.voronoi() 
                            .x(function(d) { return x(d.x); }); 
                voronoi.y(function(d) { return y(d.y); }) 
                // Setting the extent using voronoi.extent() function  
                .extent([[0, 50], [250, 380]]); 
                      
            svg.append("g").selectAll("path") 
                .data(voronoi(data).polygons()) 
                .enter() 
                .append("path") 
                .attr("d", (d)=>{ return d ? ("M" + d.join("L") + "Z"):null; }) 
                .attr("fill", "green") 
                .attr("stroke", "black"); 
        }); 
  
        // Data for CSV file 
        // x, y, group 
        // 45, 4.4, H 
        // 9.1, 4.4, H 
        // 9.9, 9.9, H 
        // 4.45, 9.6, H 
        // 4, 7.6, H 
        // 9, 45, H 
        // 4, 9.7, H 
        // 9.7, 4.7, H 
        // 9.9, 4.5, H 
        // 4, 4.5, H 
        // 7.9, 9, H 
        // 9.9, 45, H 
        // 9, 4.4, H 
    </script>  
</body>  
</html>

輸出：

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 voronoi.extent() 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。