[vox-tech] Graphing Analysis

[Jay Strauss]

Hi,

I'm doing some data analysis, stock data analysis to be exact, but I figure
it might as well be anything one could graph.  I want to find peaks and
valleys.  I want to do with my computer what I do naturally with my eyes.
So for example, some random set like this series:

3, 4, 6, 2, 7, 8, 8, 7, 6, 5, 4, 5, 6, 7, 8, 9, 11, 13,14,13, 9, 8, 9, 10,
11, 12, 15, 20, 15...

I can visually, if I put my face directly up to the paper (i.e look at each
number with regard to only the numbers directly before and after) pick out
peaks and valleys:
peaks: 6, 8, 14, 20
valleys: 3, 2, 4(after the 8), 8 (after 14)

so if I graphed this I'd use: 3,6,2,8,4,14,8,20

Then again if I pull the paper a little away, look at it with regard to 5
numbers before and after my current number, I'd say my series is:
3,8,4,14,8,20

That is, 8 was the highest number, in the 5 points after the initial data
point of 3, also as a whole, the numbers were growing up to the 8, then
decreased to the 4, then grew till the 14, then decreased till the 8, grew
till 20.

If I pull the paper far enough away I have 2 points:
3, 20

What I'm asking is there some math function(s) for analyzing trends and
graphs.  Or do I need to write functions for doing what I'm doing with my
eyes?

Thanks
Jay