LSQADJ - 2D Classical Least Squares Adjustment

All surveys have errors.  Instrument and equipment inaccuracy, user differences and individual interpretations ALWAYS result in small (hopefully!) errors in the closure.  The only TRUE mathematical adjustment is the Gaussian Least Squares adjustment which assumes that a unique solution exists and it is the most probable statistical solution.

LSQADJ solves network survey adjustments using matrix theory.  Individual observations may be weighted, if desired and several "tweaks" can be applied, depending on individual preference.

While LSQADJ is a Dos (ie. command line) program - DO NOT BE FOOLED!  This is "the real deal".  LSQADJ has been used to solve a network of multiple loops (> 10 estimated) with 159 floating network points, 11 fixed points and 211 sideshots; the solution was reached in less than 4 minutes, solving 159 equations of 159 unknowns!

I am offering this program FREE - all surveyors should be using Least Squares for larger surveys!  While some of the bells and whistles might be missing (eg. ellipses of error, etc.), this program will adjust your field data.  Input is through simple text files (which can be commented) and are entered directly from field data, as per the following example:

; some control tweaks
S TITLE HUGE adjustment - the big one!
S BLUNDER_CHK no
S BLUNDER_FILE yes
S SORT_PTS yes
S DIST_RATIO 0.7 ; try to improve angles (experiment)
S ANGLE_IBF yes ; ** use INTSTR BS FS **

; a few points
P 3 2908.57380830 7279.40935728
P 4 2941.87638350 7297.63996320
P 5 2968.27783482 7312.09273305

; some data, Traverse, Angle and Distance records
T 1 2 100 103.4911 40.808 ; oip
T 1 2 132 198.1613 20.468 ; ipf
T 1 2 3 187.5114 60.075 ; averaged
A 19 1 3 180 fixed ; on line
D 3 19 4.732
 

Installation is a simple ZIP file extraction.

DOWNLOAD LSQADJ

Current version: 1.2 (November, 2004)

Download LSQADJ here, along with a help file (LSQHELP.TXT) explaining usage, etc. sample files, etc.

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