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SilverBack
11-29-2005, 11:34 AM
I just spent 30 minutes typing a thread and it timed out! Okay, here it goes again..

Background information:
I flew a satellite to 98,000 feet. The satellite took pictures every 00:01:57 for a total of 70 images. I have to find out what altitudes the satellite was at for every image it took. There was a telemetry device onboard that was to transmit information back every 30 seconds, but due to atmospheric interference and some glitch, it didn't do what it was supposed to. You can see the flight information at:
http://astro_wx.mae.okstate.edu/astro-03/

To keep this short and from timing out again I'll be conceise.

LinEst- didn't work due to the hh:mm:ss time format (I'm assuming that's why).

(y2-y1)/(x2-x1)- same problem

Assigning each second to its own array- received an overflow.

These are the things I've tried, and the results. My best guess for the next attempt is to get the time intervals into integer form, which means seconds, but a flight lasting that long is going to produce some very large numbers if measured that way.

If anyone has done this before or knows how I might structure my next attempt please give me a reply! I'm scraping the bottom of the barrel!

Thanks in advance.

mdmackillop
11-29-2005, 01:37 PM
Hi Silverback,
Welcome to VBAX.
I've played around and added some columns to your data. As the Chart seems pretty well straight line, I've used a simple interpolation function to get the photo altitudes.
Regards
MD

SilverBack
11-29-2005, 03:29 PM
Thanks a bunch for the help! I spent the last 3 weeks working on that. I've sent a copy of what I had. It's pretty messy-the instructor requires comments for everything and a certain format. Some of it isn't complete so you'll have to disregard it. I believe it's the "practice" subroutine that I was using for the estimation. There's also a chart that I got on Sheet1, it defaults to Sheet2.

One last thing, if it's not too much trouble. My programming class is a dumbed-down version for engineers. It's meant as an introduction to programming, and I haven't nor will I see the functions you're using. However, I'm trying to teach myself VB.NET, so I'll be going on further than and introductory class. Anyway, is it possible that you can add some comments in your code so I can figure out what you've done? If I look at it long enough I'll probably be able to read it, but I couldn't recreate it.

Thanks again!

mdmackillop
11-29-2005, 04:23 PM
I've updated my zip file with some comments. It's not the tidiest code, just for my own use here really, but it saves a lot of fiddly calcs.

SilverBack
12-03-2005, 08:05 PM
Thanks a bunch for the help. Like I said what you wrote is really unfamiliar to me, but I figured it out with the comments!


I've updated my zip file with some comments. It's not the tidiest code, just for my own use here really, but it saves a lot of fiddly calcs.

mdmackillop
12-04-2005, 04:07 AM
Hi Silverback,
If this question is concluded, you can mark it Solved usting the Thread Tools dropdown above. Looks like you've done a lot of "figuring out" :thumb .
BTW, watch out for info included by Excel in File/Properties. You may not alway wish to show the name of your company etc.
Regards
MD