Too many data points in set. Looking for ways to prune.

Question

I am gathering data from a website. I estimate to get 10.000 datapoints (time - value) multipled by seven - over time. That is way to much. Both for storing and plotting it in a real time alike graph (through jQuery flot). I'm looking for a text dealing with this sort of problems. To be more precise: algorithms, statistical math for finding least significant points (if that would be a good idea), general ideas on dealing with this sort of problem. If a text were available on the net that be great. Reference to a book would do also.

Answer 1

Reading the apha beta pruning article on Wikipedia I came up with this idea: The least significant point is the point where the smallest change took place. In the data array that would be the difference between arr[i-1] and arr[i+1]. Then it's easy to find i:

var smallest = 10000; // large to start with
var rememberI = 0;
function prune(arr){
    for(i in arr){
        if(i > 0 && i < arr.length){
            var test = arr[i+1] - arr[i-1];
            if(test < smallest){
                smallest = test;
                rememberI = i;
            }
        }
    }
    return rememberI;
}

I haven't tested it yet, but it looks like a promising idea.