D3.js scaleLog() Function

Last Updated : 23 Aug, 2020

The d3.scaleLog() function is used to create a new continuous scale with the user-defined domain and range, the default base is 10. clamping is disabled by default in this scale.

Syntax:

d3.scaleLog([[domain, ]range])

Parameters: This function accepts two parameters as mentioned above and described below.

domain: This parameter always accepts two or more than two numbers. Default value is [1, 10].
range: This parameter accepts a number or a string array. It’s default value is [0, 1].

Return Value: This function returns the newly created continuous scale.

Below given are a few examples of the function given above.

Example 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> 
        var log = d3.scaleLog() 
            .domain([1, 10]) 
            .range([10, 20, 30, 40, 50, 60]); 
        console.log(log(1)); 
        console.log(log(2)); 
        console.log(log(3)); 
        console.log(log(4)); 
    </script> 
</body> 
  
</html> 

Output:

Example 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> 
        var log = d3.scaleLog() 
            .domain([-1, 1]) 
            .range([10, 20, 30, 40, 50, 60]); 
  
        // Returns NaN as Domain cant be less than one 
        console.log("Domain in log scale cannot" 
            + " be less than one : ", log(1)); 
              
        var log = d3.scaleLog() 
            .domain([10, 100]) 
            .range(["red", "green", "blue", "white"]); 
        console.log("log(1): ", log(1)); 
        console.log("log(1.5): ", log(1.5)); 
    </script> 
</body> 
  
</html> 