D3.js sequential.copy() Function

Last Updated : 31 Aug, 2020

The sequential.copy() function in D3.js is used to construct and return a copy of the original scale. Any changes in original scale will not affect the copy scale and vice-versa. Sequential scales are similar to continuous scales. In a continuous scale, mapping is done in a continuous way between domain and range. The only difference is that the output range of this scale is fixed by its interpolator and this range cannot be changed.

Syntax:

sequential.copy()

Parameters: This function does not accept any parameters.

Return Values: This function returns the copy of the original scale.

Below given are a few examples of sequential.copy() in D3.js:

Example 1:

HTML

<!DOCTYPE html> 
<html> 
  
<head> 
    <script src="https://d3js.org/d3.v6.min.js"> 
    </script> 
</head> 
  
<body> 
    <h2 style="color:green"> 
        GeeksforGeeks 
    </h2> 
  
    <h4> D3.js | sequential.copy() Function </h4> 
      
    <script> 
        var sequential = d3.scaleSequential(); 
  
        // Default scale is identity function 
        document.write("<h4>From original scale:</h4>") 
  
        document.write("<p>sequential(0.2): ",  
                    sequential(0.2) + "</p>"); 
          
        document.write("<p>sequential(0.5): ",  
                    sequential(0.5) + "</p>"); 
  
        // Creating copy of the original scale 
        var sequentialCopy = sequential.copy(); 
        document.write("<h4>From copy scale:</h4>") 
        document.write("<p>sequentialCopy(0.2): ",  
                    sequentialCopy(0.2) + "</p>"); 
  
        document.write("<p>sequentialCopy(0.5): ",  
                    sequentialCopy(0.5) + "</p>"); 
    </script> 
</body> 
  
</html> 

Output:

Example 2: Any change in the copy scale does not affect the original scale.

HTML

<!DOCTYPE html> 
<html> 
  
<head> 
    <script src="https://d3js.org/d3.v6.min.js"> 
    </script> 
</head> 
  
<body> 
    <h2 style="color:green"> 
        GeeksforGeeks 
    </h2> 
  
    <h4> D3.js | sequential.copy() Function </h4> 
  
    <script> 
        var sequential = d3.scaleSequential(); 
  
        // Default scale is identity function 
        document.write("<h4>From original scale:</h4>"); 
  
        document.write("<p>sequential(0.4): ",  
                    sequential(0.4) + "</p>"); 
        document.write("<p>sequential(0.6): ",  
                    sequential(0.6) + "</p>"); 
  
        // Creating copy of the original scale 
        var sequentialCopy = sequential.copy(); 
        sequentialCopy.domain([1, 2]); 
        document.write( 
        "<h4>From copy scale after changing domain:</h4>"); 
  
        document.write("<p>sequentialCopy(0.4): ",  
                    sequentialCopy(0.4) + "</p>"); 
        document.write("<p>sequentialCopy(0.6): ",  
                    sequentialCopy(0.6) + "</p>"); 
    </script> 
</body> 
  
</html> 