Least Squares "Excluded Observations"

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K Smith
Posts: 17
Joined: Thu Jan 06, 2005 10:02 am
Location: Surrey, BC., Canada

Least Squares "Excluded Observations"

Post by K Smith » Fri Feb 11, 2005 2:02 pm

I understand that any obervations reading 0 have to be excluded which I have been doing. I noticed though that after running the adjustment if you go back to run another, whether you actually adjusted the coordinates or not, that there are many more excluded observations which are close to 0 that have been removed by the program. They all seem to be FS shots to the backsight but it is not consistent - i.e. some FS shots to the BS are left in??


Glen Cameron
Posts: 1395
Joined: Fri Nov 08, 2002 12:18 pm
Location: Corbeil, Ontario, Canada


Post by Glen Cameron » Fri Feb 11, 2005 7:36 pm

I will have to have a programmer check on this for me as I do not know what is happening right now. As soon as I hear anything I will get back to you (or someone else will).

Glen W. Cameron, C.E.T.
City of North Bay, Ontario

Posts: 2
Joined: Fri Mar 14, 2003 11:42 am
Location: Kelowna, BC

Post by Mark » Mon Feb 14, 2005 12:06 pm


The LSA program works ok, but has a few quirks, as you've found.

There is a bug in how the program is remembering your list of excluded observations when you come back to the adjustment.

When you run an adjustment, and excluded a few observations, the next time you run the adjustment, all observations with the same "to" point ID's will be excluded from the input. If you look closely, you'll see that this is what has happened to you. You'll have to re-insert these back into the computation.

It is a nuisance, but you can work around it.

Mark Cahill

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