Question

I have one array like so:

peoples = ['dick', 'jane', 'harry', 'debra', 'hank', 'frank' .... ]

And one containing keys like so:

keys  = [1, 6, 3, 12 .... ]

Now I could write something like this:

var peoplesStripedOfKeyPostions = [];

for(i = 0; i < peoples.length; i++){
    for(j = 0; j < keys.length; j++){
        if( i !== keys[j]){
            peoplesStripedOfKeyPostions.push( peoples[i] );
        }
    }        
}

If you can’t tell, I’m need to produce an array of people that is stripped of people at certain positions defined in array keys. I know there has to be a nifty and efficient way to do this, but I certainly can’t think of it. (array management not my forte).

Do you know a better way to do this? (If I get multiple working answers, jsperf determines the winner.)

Answer 1

people.filter(function(x,i){return badIndices.indexOf(i)==-1})

This will become inefficient if the badIndices array is large. A more efficient (albeit less elegant) version would be:

var isBadIndex = {};
badIndices.forEach(function(k){isBadIndex[k]=true});

people.filter(function(x,i){return !isBadIndex[i]})

(note: you cannot use a variable named keys because that is a builtin function)