Question

This seems pretty basic, but I can’t find the best method to do this… I’m trying to set up a function that loops between a user selected start and end variables. This is what I ended up with but I’m sure there is a better way to do it (demo).

Note: the x & y variables are indexed to one, not zero.

getWidths1 = function(x, y) {
    var start = (x < y) ? x : y,
        end = (x < y) ? y : x,
        total = 0;
    for (; start < end; start++) {
        total += values[start - 1] || 0;
    }
    return total;
};

I tried this function, but the results are one result off when y > x:

getWidths2 = function(x, y) {
    var total = 0,
        diff = (x < y) ? 1 : -1;
    while (x !== y) {
        total += values[x - 1] || 0;
        x += diff;
    }
    return w;
};

So, is the first function the best, or does someone have a better method?

Answer 1

The first isn’t bad. I think this is slightly more traditional:

for (var i = start; i < end; i++){

}

Only real difference is that it doesn’t affect start and end.