Example of a Triad Solution
A boundary survey is required of Lot "B" (below)
to reestablish the missing corners. The coordinates of the map
corners and the found monuments are retrieved from an ASCII (plain
text) data file. See the following explanation of a sample printout
(the Program Manual contains a detailed example)
********************** STEP ONE: INITIAL SOLUTION *********************
The record map is best fit to the five found
monuments using the coordinates of common points. The largest
error or residual is from the calculated position of #403 to the
found monument #3 shown below as *181° in azimuth (S 1°W) 0.81'.
The best rotation and scale is determined with a 68% probable
error indicated by the Standard Deviation.
Map Pts

Field Pts

Rectangular Differences

Polar Differences

System 1 to

System 2

North (Lat)

East (Dep)

N. AZIM

DIST

"402

"2

".004

"+.104

"92°

".104

"*403

"3

".809

".010

"*181°

"*.809

"404

"4

"+.475

"+.447

"43°

".653

"406

"6

"+.225

".137

"328°

".263

"407

"7

"+.113

".404

"286°

".419

Standard Deviation of the latitudes and departures = 0.39 
Scale Factor = 1.00004129 
Standard Deviation = .00038340 
Rotation =  1° 09' 54.3" 
Standard Deviation = 0° 01' 19.1" 
********************* STEP TWO: BLUNDER DETECTION*********************
This option determines the largest error that
would remain after rejecting each of the found monuments indicated
below. Rejecting #3 will reduce the largest error in the Initial
Solution from 0.81'at #3 (above) to *0.13' at #6. The rotation
and scale that would result follow on the same line.
REJECT
POINT #

MAXIMUM RESIDUAL

ROTATION

SCALE

N. AZIM

DIST > PT #

2

181°

.79

3

001° 10' 07"

1.000059

* 3

138°

*.13

* 6

001° 09' 29"

.999336

4

88°

.45

2

001° 10' 50"

1.000368

6

180°

.72

3

001° 09' 42"

1.000090

7

181°

.66

3

001° 09' 21"

1.000237

* It can be seen by inspection that the best solution
will be obtained after rejecting #3. Triad will automatically
search and report this fact.
********************* STEP THREE: FINAL SOLUTION ********************
Point #3 is rejected by setting the pair 403,
3 "FREE". The solution is recomputed to best fit the
remaining monuments. The calculated corner positions now fall
between 0.06' to 0.13' of the found monuments as shown below.
Map Pts

Field Pts

Rectangular Differences

Polar Differences

System 1 to

System 2

North (Lat)

East (Dep)

N. AZIM

DIST

402

2

+.055

0.055

314°

0.08

403

3

1.611

.021

180°

1.61 FREE

404

4

+.037

+.049

53°

.06

406

6

.096

+.085

138°

.13

407

7

+.004

.079

272°

.08

Root Mean Square of the North and East Residuals = 0.06 (#3 excepted) 
Scale Factor = 0.99933648 
Standard Deviation = .00009303 
Rotation =  1° 09' 29.9" 
Standard Deviation = 0° 00' 19.2" 
***************** STEP FOUR: CREATE NEW COORDINATES *****************
New coordinates are computed for mapping and
staking. To avoid conflicts in the coordinate file a value of
100 is added to the map point numbers for the new points computed
in the field coordinate system.
Map Coordinates (input)

Field Coordinates (output)

PROBABLE ERROR

PT#

NORTH

EAST

PT#

NORTH

EAST

403

2748.923

5023.754

503

19315.877

39960.416

.13

405

3350.321

5042.829

505

19917.139

39967.325

.07

Note, there is an expectation at the 68% level
of confidence that the computed positions of corners #403 and
#405 are radially within 0.13' and 0.07'. This is useful in determining
the reliability of the position or for an estimated corner search
radius.
SYSTEM REQUIREMENTS:
SYSTEM REQUIREMENTS: WINDOWS XP, Windows 7, 8.1, and 10  PURCHASE
PRICE $445.00
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Tel. 8059643520
