Wednesday, August 17, 2011

Half a million and counting

kw: computers, software

Just a quick note on something that has been taking up my time. I've been wanting to analyze asteroid distributions for some time, and I recently began using Office 2010. Excel 2010 is not limited to 65,535 rows the way Excel 2003 is; its default limit is 1,048,575, and there is a way to make that larger.

Last evening I downloaded the Asteroid Orbital Elements database from Lowell Observatory. It took about an hour, being a 143-Megabyte text file. It includes about thirty parameters for more than half a million minor planets. Just opening it in Excel 2010 and getting the columns set up correctly took a while.

I extracted the columns I care about to another workbook, which then had some 34 Mby. I found that my computer is pretty fast, doing trigonometric calculations on the entire set in about three seconds. I don't know what that is in MFlops, but I was impressed.

I have more selecting to do. I'm separating out two data sets, the major part of the Main Belt and the trans-Neptune objects. Then I'll be able to do the statistical work I've been waiting on. The more I use Office 2010 the better I like it.

No comments: