The d3.mean() function in D3.js is used to return the mean or average of the given array’s elements. If the array is empty then it returns undefined.
Syntax:
d3.mean(Array)
Parameters: This function accepts a parameters Array which is an array of elements whose mean are to be calculated. Here elements should be integers not string otherwise it returns undefined.
Return Value: It returns the mean or average of the given array’s element.
Below programs illustrate the d3.mean() function in D3.js.
Example 1:
<html> <head> <title> Getting mean of the elements of given array </title> </head> <body> </script> <script> // initialising the array of elements var Array1 = [10, 20, 30, 40, 50, 60]; var Array2 = [1, 2]; var Array3 = [0, 1.5, 6.8]; var Array4 = [.8, .08, .008]; // Calling to d3.mean() function A = d3.mean(Array1); B = d3.mean(Array2); C = d3.mean(Array3); D = d3.mean(Array4); // Getting mean of the given array's element document.write(A + "<br>" ); document.write(B + "<br>" ); document.write(C + "<br>" ); document.write(D + "<br>" ); </script> </body> </html> |
Output:
35 1.5 2.766666666666667 0.296
Example 2:
<html> <head> <title> Getting mean of the elements of given array </title> </head> <body> </script> <script> // initialising the array of elements var Array1 = []; var Array2 = [ "a" , "b" , "c" ]; var Array3 = [1, "B" , "C" ]; var Array4 = [ "Geek" , "Geeks" , 2, 3, "neveropen" ]; // Calling to d3.mean() function A = d3.mean(Array1); B = d3.mean(Array2); C = d3.mean(Array3); D = d3.mean(Array4); // Getting mean of the given array's element document.write(A + "<br>" ); document.write(B + "<br>" ); document.write(C + "<br>" ); document.write(D + "<br>" ); </script> </body> </html> |
Output:
undefined undefined 1 2.5
Note: In the above output, if the parameter is empty or strings then it returns undefined and if the parameter is string including some integers value then the mean of the integer’s value is returned.
Ref: https://devdocs.io/d3~4/d3-array#mean