# Algorithm Help

• September 10th, 2010, 12:15 PM
aussiemcgr
Algorithm Help
I need some help creating an algorithm.

Here is the problem:

I have 2 fixed numbers, and then an array of numbers.

The first fixed number represents data for a monthly period. The second fixed number represents a percentage changed for the monthly period from the data this week to the data last week.

The array of numbers is a list of event that occured which caused in the percentage change.

The problem is the array of numbers can include data that had no real effect on the percentage change, so we dont want to include it. So I need an algorithm that can go through the array of numbers and determine what sort of effect it had on the percentage. If it has a large enough effect, print it out, if not, get rid of it. I also want to get rid of data that doesnt agree with the percentage change. For example, if the percentage change is negative, there should be no positive data included in the array of numbers.

Here is an example test case:
Fixed Number 1 = 45,499,632
Fixed Number 2 = -2.4%
Array of Numbers = {-150; 750; -319; 60; -1456; -700; -6420; -700; -350; -147; -290}

So, when we look at the percentage and notice it is negative, we want to get rid of all the positive numbers, which brings our array down to:
Array of Numbers = {-150; -319; -1456; -700; -6420; -700; -350; -147; -290}

Now we want to have a look at the impact of each number of the percentage. Using common sense, I would narrow it down our Array of Numbers to:
Array of Numbers = {-1456; -700; -6420; -700;}

That seems about right, you might even consider removing the -700s as well.