Controlling program flow across cells

*To*: mathgroup at smc.vnet.net*Subject*: [mg54368] Controlling program flow across cells*From*: semiclassical at hotmail.com (semiclassical)*Date*: Sat, 19 Feb 2005 02:32:22 -0500 (EST)*Sender*: owner-wri-mathgroup at wolfram.com

Here is the problem: I import a large data file - 20 years of hourly observations, which is used to populate a raw data list of approximately 176,000 rows with the following structure: {year, day, hour, validity_Flag, data_Item1, ... ,data_Item5} The list is then parsed, filtered and operated upon in several different ways. In particular I calculate statistical properties of a specified 5 year period. The process is encapsulated in a number of cells- Cell_1 : Parse[ Import and filter raw data ]; Cell_2a: Parse[ Chip out and sort period of interest ]; Cell_2b: Calculate[ statistical properties of validity_Flag ]; Cell_2c: Calculate[ statistical properties of data_Item ]; Cell_2d: Calculate[ distribution of data_Item ]; This is done for most data_Items, additionally calculations are made for hourly statistics and quartely statistics. Now what I would like to be able to do is loop over the four 5 year periods within the complete 20 year span. Here are two questions: 1. I would like to set up a For[] loop across Cell_2a-Cell_2d to loop through the four periods of interest. How can I do this, or should I actually have built the program in a different way? 2. How can I get output from within a For[] loop as it is executing? For example, I might like to watch some value of a given variable within the loop as it is calculated (in C I would use a printf). Thanks, Aaron semiclassical at hotmail.com