Extracting Specfic range of values within javascript array

why overcomplicate things:

var volumeData = [], l = jsonData.length;
while (l--) {
    var d = Date.parse(jsonData[l].date);
    if (d >= startdate && d <= endate) { 
        volumeData.push(jsonData[l].volume) 
    };
} 

First, you need to put your dates into a standard numeric format, not a human readable one.

Use (for example) the datejs library to do the conversion, or just use yyyymm instead.

Once you've done that, the rest should be obvious. Only convert back to human readable format at the last possible moment.

Edit - Ignore this answer: use @herostwist's answer; it's much simpler :)

There are a few stages to this:

To make things easier, you need to sort the data so we can extract a subset. Unfortunately, doing a naive sort by date will order them alphabetically, so we need to convert the date labels into something useful - i.e. numerical. (Note, Date.parse

for(var i=0, len=jsonData.length; i<len; i++) {
  jsonData[i].date = Date.parse(jsonData[i].date);
}

Then we can sort the data array:

jsonData.sort(function(a, b) {
  return a.date < b.date ? -1 : 1;
});

Then iterate through the array until you find the first instance of the lower bound:

var lower = Date.parse('Jan 2004'),
    lower_index = -1;

for(var i=0, len=jsonData.length; i<len; i++) {
  if(jsonData[i].date === lower) {
    lower_index = i;
    break;
  }
}

And the last instance of the upper bound:

var upper = Date.parse('November 2004'),
    upper_index = -1;

for(var i=0, len=jsonData.length; i<len; i++) {
  if(jsonData[i].date === upper) {
    upper_index = i;
  }
}

Then you can take a slice of the original data and construct your subset:

var data = jsonData.slice(lower, upper+1),
    volumeData = [];

for(var i=0, len=jsonData.length; i<len; i++) {
  volumeData.push([i, data[i].volume]);
}