I have a data file with 11000 rows and 4 columns. I need to read all values (in all columns) for data between each maximum and each minimum of column 3. Integrate column 3 and column 4, and calculate the mean of column 2, for each range between the maximum and minimum of column 3. Do I make sense?? I am really unsure about how to start. I am using Matlab2015a. I have attached what I want to do as image. For rudimentary case I can do like shown on the right in figure. But it would take a decade to solve. Need help.