MapCheck Not working properly

genuine.software · ‎12-26-2023

Issue: When running Mapcheck under Survey, I receive different area calculations. When we use the area line command it also shows a different area. The report from the Mapcheck after closure adjustment is for an example used, is 2000 feet off from the other area calculations.

So for the object see in screenshot: 1 and 4 PNG file attached with this thread.

This is a serious legal issue, as I have been using the 6000 version of areas on our records, and have only just discovered that with the 4 methods, they are not matching

(map check report, map check closure summary, area of the object in properties, and area command of object)

Please advise!

Also have attached the DWG file.

nusouthsc · ‎12-26-2023

Hi,

I am not seeing the discrepancy you are referring to. All the areas I get are within 1 sq.ft. of each other. It looks like everything is working fine. Can you clarify?

Josh Ellis
Nu-South Surveying

TerryDotson · ‎12-27-2023

My impression of the MapCheck routine is that it "re-traverses" the calls as labeled for the user to check the closure (and comparison area). The area it reports would always vary from the area of a closed polyline running through the points, I believe that's why the "Polyline" the MapCheck tool produces is always an open polyline (final segment drawn to a point near the POB) as opposed to a traditional closed polyline (no final segment).

The area will vary and will vary more depending on the closure ratio of the figure. With rounding to two places and bearings to the nearest second, only a simple rectangle is likely to close 1/Infinity. The MapCheck area varies and should not be considered anything other than a comparison value.

DotSoft: The Leading Developer
of AutoCAD Add-on Utilities

_Hathaway · ‎12-27-2023

Correct, what Terry said. The mapcheck does just that, it checks the map values as displayed. Think of it as someone sitting down and entering in all the data from the map, that's what it does. So the line that is 134.34' long is actually 133.336' long in the drawing. You repeat that XXX # of times and your end area should be different in the mapcheck when compared to the actual true linework area in your drawing.

genuine.software · ‎12-27-2023

There is a discrepancy and your software has caused me humiliation.

The area command and the list are copied entities

Area command

Area = 8141.0822, Length = 430.3013

Mapcheck

Adjust mapcheck (this is the one we use)

RAW TRAVERSE No RULE - Balanced Angles

Point Coordinates Coordinates Delta

1 N 13752142.9326 N 13752142.9326 0.0000

E 2078261.5531 E 2078261.5531

S 00-10-52 E Dist:50.0000

2 N 13752092.9329 N 13752092.9329 0.0000

E 2078261.7112 E 2078261.7112

N 90-00-00 W Dist:11.4200

3 N 13752092.9329 N 13752092.9329 0.0000

E 2078250.2912 E 2078250.2912

N 45-00-00 W Dist:120.2100

4 N 13752177.9342 N 13752177.9342 0.0000

E 2078165.2899 E 2078165.2899

N 00-00-00 W Dist:46.8800

5 N 13752224.8142 N 13752224.8142 0.0000

E 2078165.2899 E 2078165.2899

N 13-04-52 W Dist:15.8400

6 N 13752240.2432 N 13752240.2432 0.0000

E 2078161.7048 E 2078161.7048

S 78-53-29 E Dist:54.6100

7 N 13752229.7215 N 13752229.7215 0.0000

E 2078215.2916 E 2078215.2916

S 00-00-00 E Dist:51.7800

8 N 13752177.9415 N 13752177.9415 0.0000

E 2078215.2916 E 2078215.2916

S 45-00-00 E Dist:49.5000

9 N 13752142.9397 N 13752142.9397 0.0000

E 2078250.2934 E 2078250.2934

N 90-00-00 E Dist:11.2700

1 N 13752142.9397 N 13752142.9397 0.0000

E 2078261.5634 E 2078261.5634

Angular error = 0-00-00

Angular error/set = 0-00-00 Under

Error North : -0.0071

Error East : -0.0103

Absolute error : 0.0125

Error Direction : S 55-28-42 W

Perimeter : 411.5100

Precision : 1 in 32981.2810

Number of sides : 9

Area : 6428.8 sq. ft. , 0.1476 Acres

Map check

Closure Summary

Mapcheck 3: Parcel 4

Closure Summary

Precision, 1 part in: 34537.29'

Error distance: 0.01'

Error direction: N55° 30' 58"E

Area: 8141.23 Sq. Ft.

Square area: 8141.225

Perimeter: 430.30'

Point of Beginning

Easting: 2078261.5531'

Northing: 13752142.9326'

Side 1: Line

Direction: S0° 10' 52"E

Angle: [-0.1811 (d)]

Deflection angle: [179.8189 (d)]

Distance: 50.00'

Easting: 2078261.7112'

Northing: 13752092.9329'

Side 2: Line

Direction: N90° 00' 00"W

Angle: [-89.8189 (d)]

Deflection angle: [90.1811 (d)]

Distance: 11.42'

Easting: 2078250.2912'

Northing: 13752092.9329'

Side 3: Curve

Curve direction: Clockwise

Radius: [85.00']

Arc length: 133.52'

Delta angle: 90.0000 (d)

Tangent: [85.00']

Chord direction: N45° 00' 00"W

Chord angle: [-135.0000 (d)]

Deflection angle: [45.0000 (d)]

Chord distance: 120.21'

Easting: 2078165.2899'

Northing: 13752177.9342'

Side 4: Line

Direction: N0° 00' 00"E

Angle: [180.0000 (d)]

Deflection angle: [-0.0000 (d)]

Distance: 46.88'

Easting: 2078165.2899'

Northing: 13752224.8142'

Side 5: Line

Direction: N13° 04' 52"W

Angle: [166.9189 (d)]

Deflection angle: [-13.0811 (d)]

Distance: 15.84'

Easting: 2078161.7048'

Northing: 13752240.2432'

Side 6: Line

Direction: S78° 53' 29"E

Angle: [-65.8103 (d)]

Deflection angle: [114.1897 (d)]

Distance: 54.61'

Easting: 2078215.2916'

Northing: 13752229.7215'

Side 7: Line

Direction: S0° 00' 00"E

Angle: [-101.1086 (d)]

Deflection angle: [78.8914 (d)]

Distance: 51.78'

Easting: 2078215.2916'

Northing: 13752177.9415'

Side 8: Curve

Curve direction: Counter-clockwise

Radius: [35.00']

Arc length: 54.98'

Delta angle: 90.0000 (d)

Tangent: [35.00']

Chord direction: S45° 00' 00"E

Chord angle: [135.0000 (d)]

Deflection angle: [-45.0000 (d)]

Chord distance: 49.50'

Easting: 2078250.2934'

Northing: 13752142.9397'

Side 9: Line

Direction: N90° 00' 00"E

Angle: [-180.0000 (d)]

Deflection angle: [0.0000 (d)]

Distance: 11.27'

Easting: 2078261.5634'

Northing: 13752142.9397'

List command

LWPOLYLINE Layer: "E_Boundary_Lines"

Space: Model space

Color: BYLAYER Linetype: "BORDER2"

Handle = 10c59

Open

Constant width 0.0000

area 8141.0822

length 430.3013

at point X=2078560.9019 Y=13752484.7111 Z= 0.0000

bulge 0.4142

center X=2078595.9019 Y=13752484.7111 Z= 0.0000

radius 35.0000

Press ENTER to continue:

start angle 180

end angle 270

at point X=2078595.9019 Y=13752449.7111 Z= 0.0000

at point X=2078607.1687 Y=13752449.7111 Z= 0.0000

at point X=2078607.3267 Y=13752399.7111 Z= 0.0000

at point X=2078595.9019 Y=13752399.7111 Z= 0.0000

bulge -0.4142

center X=2078595.9019 Y=13752484.7111 Z= 0.0000

radius 85.0000

start angle 270

end angle 180

at point X=2078510.9019 Y=13752484.7111 Z= 0.0000

at point X=2078510.9019 Y=13752531.5918 Z= 0.0000

at point X=2078507.3161 Y=13752547.0239 Z= 0.0000

Press ENTER to continue:

at point X=2078560.9019 Y=13752536.5023 Z= 0.0000

at point X=2078560.9019 Y=13752484.7213 Z= 0.0000

Your analysis is incorrect because it does not justify the error. In this case, a closure error of .01 is not going to equate to a 1500 sq. ft. error. The mapchecks are within the same pop up.

nusouthsc · ‎12-27-2023

I have never used the Mapcheck adjust you are referring to. I simply type in “MAPCHECK” and have never had an issue. I took your drawing and joined the lines and got the same area as the Mapcheck. Be certain the Mapcheck function works. Obviously there is something being used wrong to get wrong results. I would suggest testing the accuracy compared to a square figure you can easily calculate the area for. Or a simple triangle. We have used Mapcheck for years and love it.

Josh Ellis
Nu-South Surveying

TerryDotson · ‎12-27-2023

There is a discrepancy and your software has caused me humiliation.

Major Correction: Autodesk Authorized Developer (My Logo) DOES NOT indicate that I am employed by Autodesk, Inc. In contrast we (DotSoft LLC) are one of many independent developers and not only are we not employed by Autodesk, we pay a significant fee annually just for the right to enhance their products with optional add-ons.

In the future you should look at ALL of the details of any situation before you jump to a conclusion, and the MapCheck situation may not be out of that realm. I was simply trying to help by pointing out another possibility but will be read-only on this thread going forward.

DotSoft: The Leading Developer
of AutoCAD Add-on Utilities

BrianHailey · ‎12-28-2023

Looking at your drawing, the mapcheck details don't match the labels in your drawing. Perhaps something changed and wasn't updated in the mapcheck?

And @TerryDotson is a fantastic contributor to this forum. There aren't many (if any) that are more overall knowledgeable in Autodesk AEC software than Terry. When he posts, we should all pay attention.

Brian J. Hailey, P.E.

GEI Consultants
My Civil 3D Blog

Jeff_M · ‎12-28-2023

@genuine.software wrote:

There is a discrepancy and your software has caused me humiliation.

Mapcheck

Adjust mapcheck (this is the one we use)

RAW TRAVERSE No RULE - Balanced Angles

Point Coordinates Coordinates Delta

1 N 13752142.9326 N 13752142.9326 0.0000

E 2078261.5531 E 2078261.5531

S 00-10-52 E Dist:50.0000

2 N 13752092.9329 N 13752092.9329 0.0000

E 2078261.7112 E 2078261.7112

N 90-00-00 W Dist:11.4200

3 N 13752092.9329 N 13752092.9329 0.0000

E 2078250.2912 E 2078250.2912

N 45-00-00 W Dist:120.2100

4 N 13752177.9342 N 13752177.9342 0.0000

E 2078165.2899 E 2078165.2899

N 00-00-00 W Dist:46.8800

5 N 13752224.8142 N 13752224.8142 0.0000

E 2078165.2899 E 2078165.2899

N 13-04-52 W Dist:15.8400

6 N 13752240.2432 N 13752240.2432 0.0000

E 2078161.7048 E 2078161.7048

S 78-53-29 E Dist:54.6100

7 N 13752229.7215 N 13752229.7215 0.0000

E 2078215.2916 E 2078215.2916

S 00-00-00 E Dist:51.7800

8 N 13752177.9415 N 13752177.9415 0.0000

E 2078215.2916 E 2078215.2916

S 45-00-00 E Dist:49.5000

9 N 13752142.9397 N 13752142.9397 0.0000

E 2078250.2934 E 2078250.2934

N 90-00-00 E Dist:11.2700

1 N 13752142.9397 N 13752142.9397 0.0000

E 2078261.5634 E 2078261.5634

Angular error = 0-00-00

Angular error/set = 0-00-00 Under

Error North : -0.0071

Error East : -0.0103

Absolute error : 0.0125

Error Direction : S 55-28-42 W

Perimeter : 411.5100

Precision : 1 in 32981.2810

Number of sides : 9

Area : 6428.8 sq. ft. , 0.1476 Acres

Map check

If you look closely at the adjusted output you will see that it is based on all sides being lines, therefor it is using the chords of the 2 arcs. All adjustment types go point to point so you should not use any area calculated if there are any arcs in the parcel/polyline. Instead, use the area shown in the closure summary.

One must ask, why are you performing an adjustment? Are you editing the labels to match the adjustment?

Jeff_M, also a frequent Swamper

nusouthsc · ‎12-28-2023

Jeff,

Very keen observation! I knew it had to be something simple. So it was just the wrong tool being used. Hopefully this will help the OP in his situation. Good work Jeff! This is why I love this community!

Josh Ellis

Nu-South Surveying

Anderson, SC

Josh Ellis
Nu-South Surveying

genuine.software · ‎12-29-2023

Dear Terry,

I appreciate your clarification and the insight you've provided regarding the Autodesk Authorized Developer designation. I sincerely apologize for any misunderstanding in my previous messages. Your explanation sheds light on the independence and dedication of DotSoft LLC as an Autodesk Authorized Developer, and I value the correction.

I understand the importance of thoroughly considering all details before forming conclusions, and I'll certainly take this lesson with me. Your intention to help and provide additional perspectives is duly noted and appreciated. I'm grateful for your patience and understanding.

Moving forward, I'll ensure to approach discussions with a more comprehensive understanding. Please feel free to reach out if there are any further points you'd like to discuss or clarify.

Thank you for your time and clarification.