d3.js ordinal.copy()用法及代码示例

ordinal.copy()函数用于创建和返回序数标度的精确副本。原始比例的任何更改都不会影响复印比例，反之亦然。

用法:

ordinal.copy();

参数：此方法不带任何参数。

返回值：此方法返回原始比例的副本。

范例1：

HTML

<!DOCTYPE html> 
<html lang="en"> 
  
<head> 
    <meta charset="UTF-8" /> 
    <meta name="viewport" path1tent= 
        "width=device-width,  
        initial-scale = 1.0" /> 
  
    <script src= 
        "https://d3js.org/d3.v4.min.js"> 
    </script> 
</head> 
  
<body> 
    <script> 
  
        // Creating the Ordinal scale. 
        var ordinal = d3.scaleThreshold() 
  
            // Setting domain for the scale 
            .domain([1, 2, 3, 4]) 
            .range([10, 20, 30, 40]); 
  
        // Making copy of the scale. 
        var ordinalCopy = ordinal.copy(); 
        console.log("The value of ordinalCopy(1) is:", 
                ordinalCopy(1)); 
        console.log("The value of ordinalCopy(2) is:", 
                ordinalCopy(2)); 
        console.log("The value of ordinal(1) is:", 
                ordinal(1)); 
        console.log("The value of ordinal(2) is:", 
                ordinal(2)); 
    </script> 
</body> 
  
</html>

输出：

范例2：

HTML

<!DOCTYPE html> 
<html lang="en"> 
  
<head> 
    <meta charset="UTF-8" /> 
    <meta name="viewport" path1tent= 
        "width=device-width,  
        initial-scale = 1.0" /> 
  
    <script src= 
        "https://d3js.org/d3.v4.min.js"> 
    </script> 
</head> 
  
<body> 
    <script> 
  
        // Creating the Ordinal scale. 
        var ordinal = d3.scaleThreshold() 
          
            // Setting domain for the scale 
            .domain([1, 2, 3, 4]) 
            .range([10, 20, 30, 40, 50]); 
          
        console.log("The value of ordinal(3) is:", 
                ordinal(3)); 
        console.log("The value of ordinal(4) is:", 
                ordinal(4)); 
  
        // Making copy of the scale. 
        var ordinalCopy = ordinal.copy(); 
  
        // making change in the original scale. 
        ordinal.range(["The range of the " 
                + "original scale is change"]); 
        console.log("The value of ordinalCopy(3) is:", 
                ordinalCopy(3)); 
        console.log("The value of ordinalCopy(4) is:", 
                ordinalCopy(4)); 
        console.log("The value of ordinal(3) is:", 
                ordinal(3)); 
        console.log("The value of ordinal(4) is:", 
                ordinal(4)); 
    </script> 
</body> 
  
</html>

输出：

相关用法

注：本文由纯净天空筛选整理自tarun007大神的英文原创作品 D3.js ordinal.copy() Function。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。