On 2002-05-07 15:46, blueberry wrote:
The data I have is pretty simple, but you're right, there's a lot of values. I have water level data of a tidal marsh that experiences 2 high tides and 2 low tides per day, with one of the tides being higher and lower than the other. So, there's a low high tide, high high tide, low low tide and high low tide.
I'm interested in the extreme highs and lows per day and the data is set up with 3 columns. the first column is the date, column 2 is the time, and column 3 is the level of the water. And since the data's pretty extensive (we have a couple years of data every 10 or 15 minutes), I was hoping to figure out how to automate the extreme tide levels for each day and to average them over a lunar cycle. I'm not sure how to set up the min/max equation with a range that will automatically calculate the next day's and the next day's min/max and then average them by month. ...help!