Least Squares Adjustment Program (Land Surveying)

Paul in PA

Darrell- Maybe http://www.microsurvey.com/products/starnet/download_form.php

Cheers

Derek

--
"Tiz in the flux of patience that the ever vigilant is buoyed"

It seems like everyone forgets that Star*NET has a demo mode. Maybe because before MicroSurvey bought the program this past year, there wasn't even a website for it. Download the full version of the program and run it in DEMO mode. The only restriction is that you are limited to 10 points when you perform an adjustment. It should otherwise be functionally equivalent to the "Professional" version of the program (although, I notice that the converters seem to be disabled as well, but these didn't use to be included as a regular part of Star*NET before it was purchased by MicroSurvey anyway). You can still learn and do a hell of a lot with it. Maybe you will find it useful enough to buy a copy. I have to wonder how many people know about this and will find it useful?

http://www.microsurvey.com/helpdesk/index.php?_m=downloads&_a=viewdownload&down...

COLUMBUS!!!

It isn't "FREE" (although there is a free DEMO), but it won't "rape" your wallet.

$725 is a GREAT price for a Program with COLUMBUS' power and ease of use.

http://www.bestfit.com/prac_outliers.shtml

Loyal

Does not your GPS processing software (LGO, TGO, Topcon Tools etc.) have adjustment functions? Assuming you are needing it for GPS. Civil 3d has this as well, but I hear it sucks and it's DEFINITELY not easy on the wallet.

I use LGO, it's not that pricy for the processing and adjustment modules. Sorry, I know this was not what you asked but just curious.

--
Corey J Diekman, PLS, CFedS, etc.
a.k.a. Corner Stone

FWIW,

The NGS has a venerable package ADJUST that is free, rigorous and is distributed with sample data and guidelines. I consider it a good tool to learn about adjustments. I provides rich numeric output allowing close scrutiny of the processing and results.

That said, creating the input files (constraints and parameters, a priori positions and observations) for your data might be more trouble than you want. Also running the various steps in the process are all command line operations.

There is even a NOAA TM 47 describing the program and its use.

Download page is:here

The information below was copied from that page.

ADJUST_ALL [2011/01/04] Download a zip file with all PC executables, support files and documentation. Does not contain source code files.

DOWNLOADS:
adjust_all.zip contains the Adjust suite of programs for the PC.

ADJUST [version 5.6 - 2008/10/27] Performs least squares adjustment on horizontal, vertical angle, and GPS observations.

DOWNLOADS:
adjust.exe is the PC executable.
adjust_suppl52.zip contains supplemental documentation for versions 5.2 and later
samples.zip has sample data files, common to adjust, chkobs, obschk, obsdes
adjust_v56.zip contains program source code

Constrained Adjustment Guidelines -- (2010/03/04) recommended adjustment procedures and step-by-step approach for adjusting GPS projects.

Enjoy,

DMM

I find it hard to believe that every surveyor does not have a good least squares adjustment program (and is not proficient in its use). To me it is an absolutely indispensable tool. I would no more think of looking for a free LS program than I would try to get some free knives if I were a surgeon. Maybe this is indicative of the state of our profession...

This is not a personal attack on Darrell. I just think that a LS program is a fundamental tool that all surveyors should be using.

I use Geolab, and it has worked for many years for me. Very powerful. But, it does have a few bugs and is basically a dead program (i.e. no one is updating it). I have used Star*Net, but do not have it now. I didn't like it because it does things in 2D/1D rather than ECEF as Geolab does. I also have Columbus, but my way of operating is to write my own input files, and I have had problems doing that with Columbus. To be honest I have not spent a lot of time messing with it, but the ASCII text files that I made didn't work, and I haven't had time to try to fix them. Let's just say I have problems with it.

I have been interested in MOVE3, because, like Geolab, it does true 3-D adjustments. It also has capability to put in constraints like collinearity, parallel lines, perpendicular lines, etc. It is expensive, $2499. But, I believe that is in the range of what I paid for Geolab many years ago. If it works well, I am willing to spend that to get a really good program with good support. I use a least squares program way more than I use CAD, but that is because of the peculiar types of projects that I do. I downloaded the MOVE3 demo today, and tried to load a small GPS net, but it exceeds the limits of the demo (not sure what the limits actually are). They do have an option for $149 for a 60 day trial version.

I do use ADJUST from NGS, but only for GPS and only on projects which I submit for bluebooking. Not at all hard to use ONCE you get the input files correct (B files and G files).

I should add that I write a lot of software, and it is very time consuming and tedious at times. Good software is worth paying for.

Some (possibly out-of-date) info:
Global Cogo has DOS Burkord and WBK, both free.
Sayed R Hashimi (SRH) has Ez-Adjust, and Convergent Computations has Geoida, both under $400.
Don't know if they're "good" enough for you.

CMM, written for BLM by Ray Hintz at the University of Maine, includes Least Squares Adjustment. To my knowledge, because the taxpayers paid for it, there are no additional charges. Input is not too difficult, nearly as easy as Star*Net. It doesn't have all the bells and whistles Star*Net has but, it covers the basics very well. There's both a horizontal network adjustment and a vertical adjustment package. It takes a little effort in the instructions to find the least squares discussion. Once found, you should not have too much difficulty and you'll get reliable results.

See post:
by William D., Friday, February 04, 2011, 16:50 (4 hours, 21 minutes ago) @ Adam3000i

Have you looked at New Mexico State's software?

http://web.nmsu.edu/~kwurm/Software.html

If you are mostly wanting to learn then Ghilani's program is probably about the easiest to get install and learn. It is for educational purposes only, and I am not sure what other limits it has as far as size of networks etc. My recollection is that it is not severely limited. It can be downloaded here:

http://surveying.wb.psu.edu/psu-surv/free.htm

CMM is available in a number of forms. CMM is mostly a DOS era program that will run on machines up through XP. It may be considered slightly more cryptic in its use but has been used on literally 1000's of jobs in BLM. It could be useful as a learning tool also.

It does NOT have a pretty windows interface but if one is learning or willing to dig a little to learn, it can be a workhorse. It is also not just a plane survey adjustment package, as it can deal with geodetics fairly well using the SPC systems fairly rigorously applied. It was also not primarily designed as a least squares package so there are a lot of other aspects of it beyond that scope dealing with PLSS applications. It was also not designed to compete with commercial programs.

Email me if you want more info. A google search should find me fairly easily.

- jerry wahl

PS. Initial experiments with Ghilani's program for traverses seems to indicate a limited number of options for how the traverse is set up, and it does not immediately appear to me to do networks, but basic loops. It has a ton of other functions and utilities in it and is probably all related to his text books.