d3.js density.bandwidth()用法及代碼示例

density.bandwidth()函數用於設置密度估計器函數的帶寬。如果未指定帶寬，則它將設置等於20.4939的默認帶寬。如果指定了帶寬，則它將設置高斯內核的帶寬並返回估計值。

用法:

d3.contourDensity.x().y().bandwidth([bandwidth]);

參數：此函數采用上麵給出的和下麵描述的一個參數。

bandwidth:該函數采用一個數字，該數字定義了密度估計器函數的帶寬。

返回值：此函數不返回任何內容。

下麵給出了一些density.bandwidth()函數的示例。

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-contour.v1.min.js"> 
    </script> 
</head>  
  
<body>  
    <h1 style="color:green">GeeksforGeeks</h1> 
      
    <script>  
        // append the svg object to the body. 
        var svg = d3.select("body") 
        .append("svg") 
            .attr("width", 500) 
            .attr("height", 500) 
        .append("g") 
            .attr("transform", 
                "translate(" + 20 + ", " + -80 + ")"); 
  
        // read data 
        d3.csv("./data.csv", function(data) { 
              
        var y = d3.scaleLinear() 
            .domain([-5, 30]) 
            .range([ 400, 100 ]); 
  
        var x = d3.scaleLinear() 
            .domain([0, 22]) 
            .range([ 0, 300]); 
  
  
        svg.append("g") 
        .call(d3.axisLeft(y)); 
          
        svg.append("g") 
            .attr("transform", "translate(0, " + 400 + ")") 
            .call(d3.axisBottom(x)); 
  
        var density= d3.contourDensity() 
            .y(function(d) { return y(d.y); }) 
            .x(function(d) { return x(d.x); }) 
            // Use of bandwidth() Function 
            .bandwidth(40) 
            (data) 
  
        svg.selectAll("path") 
            .data(density) 
            .enter() 
            .append("path") 
            .attr("d", d3.geoPath()) 
            .attr("fill", "none") 
            .attr("stroke", "green") 
        }); 
  
        // Data for csv file 
        // x, y, group 
        // 9.45, 4.4, H 
        // 9.1, 4.4, H 
        // 9.9, 9.9, H 
        // 9.6, 4.5, H 
        // 9.1, 9.7, H 
        // 4.7, 9.5, H 
        // 7.9, 9.6, H 
        // 4.7, 9.7, H 
        // 9.45, 4.4, H 
        // 12.1, 9.4, H 
        // 7.5, 9, H 
        // 4.5, 4.5, H 
        // 9.45, 9.7, H 
        // 4.45, 9.6, H 
        // 9.5, 7.6, H 
        // 9, 9.45, H 
        // 4.7, 12, H 
        // 9.7, 9.7, H 
        // 9.6, 9, H 
        // 12, 9, H 
        // 9.45, 4.5, H 
        // 9.9, 4.6, H 
        // 12.7, 9.9, H 
        // 9, 12.4, H 
        // 9, 4.9, H 
        // 9.5, 9.7, H 
        // 9.7, 4.7, H 
        // 9.9, 4.5, H 
        // 4, 4.5, H 
        // 7.9, 9, H 
        // 9.9, 9.45, H 
        // 9, 4.4, H 
        // 4.7, 9.7, H 
        // 4.5, 9.9, 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-contour.v1.min.js"> 
    </script> 
</head>  
  
<body>  
    <h1 style="color:green">GeeksforGeeks</h1> 
      
    <script>  
  
        // append the svg object to the body. 
        var svg = d3.select("body") 
        .append("svg") 
            .attr("width", 500) 
            .attr("height", 500) 
        .append("g") 
            .attr("transform", 
                "translate(" + 20 + ", " + -80 + ")"); 
  
        // read data 
        d3.csv("./data.csv", function(data) { 
              
        var y = d3.scaleLinear() 
            .domain([-5, 30]) 
            .range([ 400, 100 ]); 
  
        var x = d3.scaleLinear() 
            .domain([0, 22]) 
            .range([ 0, 300]); 
  
  
        svg.append("g") 
        .call(d3.axisLeft(y)); 
          
        svg.append("g") 
            .attr("transform", "translate(0, " + 400 + ")") 
            .call(d3.axisBottom(x)); 
  
        var density= d3.contourDensity() 
            .y(function(d) { return y(d.y); }) 
            .x(function(d) { return x(d.x); }) 
            // Use of bandwidth() Function 
            .bandwidth(10) 
            (data) 
  
        svg.selectAll("path") 
            .data(density) 
            .enter() 
            .append("path") 
            .attr("d", d3.geoPath()) 
            .attr("fill", "none") 
            .attr("stroke", "green") 
        }); 
  
        // Data for csv file 
        // x, y, group 
        // 9.45, 4.4, H 
        // 9.1, 4.4, H 
        // 9.9, 9.9, H 
        // 9.6, 4.5, H 
        // 9.1, 9.7, H 
        // 4.7, 9.5, H 
        // 7.9, 9.6, H 
        // 4.7, 9.7, H 
        // 9.45, 4.4, H 
        // 12.1, 9.4, H 
        // 7.5, 9, H 
        // 4.5, 4.5, H 
        // 9.45, 9.7, H 
        // 4.45, 9.6, H 
        // 9.5, 7.6, H 
        // 9, 9.45, H 
        // 4.7, 12, H 
        // 9.7, 9.7, H 
        // 9.6, 9, H 
        // 12, 9, H 
        // 9.45, 4.5, H 
        // 9.9, 4.6, H 
        // 12.7, 9.9, H 
        // 9, 12.4, H 
        // 9, 4.9, H 
        // 9.5, 9.7, H 
        // 9.7, 4.7, H 
        // 9.9, 4.5, H 
        // 4, 4.5, H 
        // 7.9, 9, H 
        // 9.9, 9.45, H 
        // 9, 4.4, H 
        // 4.7, 9.7, H 
        // 4.5, 9.9, 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 density.bandwidth() 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。