The set.empty() function in D3.js is used to return true if the given array has zero elements otherwise returns false.
Syntax:
d3.set([Array]).empty();
Parameters: This function accepts single parameter Array which is going to be searched whether it is empty or not.
Return Value: It returns true if the given array is empty otherwise returns false.
Below programs illustrate the d3.set.empty() function in D3.js:
Example 1:
<!DOCTYPE html> <html> <head> <title>
d3.set.empty() function
</title>
</head> <body> <script>
// Initialising an array
Array1 = [ "a" ];
Array2 = [];
Array3 = [ "Geeks" , "gfg" , "GeeksforGeeks" ];
// Calling the d3.set.empty() function
A = d3.set(Array1).empty();
B = d3.set(Array2).empty();
C = d3.set(Array3).empty();
// Getting the value true if the given array is
// empty otherwise returns false
console.log(A);
console.log(B);
console.log(C);
</script>
</body> </html> |
Output:
false true false
Example 2:
<!DOCTYPE html> <html> <head> <title>
d3.set.empty() function
</title>
</head> <body> <script>
// Calling the d3.set.empty() function
// with a array as the parameter
A = d3.set([1, 2, 3, 3]).empty();
B = d3.set([]).empty();
C = d3.set([ "a" , "b" , "c" , "a" , "b" , "c" ]).empty();
// Getting the value true if the given array is
// empty otherwise returns false
console.log(A);
console.log(B);
console.log(C);
</script>
</body> </html> |
Output:
false true false
Ref: https://devdocs.io/d3~5/d3-collection#set_empty