error detection
DESCRIPTION
Error detection. Types of errors. Digitizing errors overshooting undershooting polygons do not close missing data. Contour lines never cross!!. An example of horrible digitizing!!!. overshooting. “dangling” node. River digitized in the wrong direction. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Error detection](https://reader036.vdocuments.mx/reader036/viewer/2022062310/568167ee550346895ddd5c76/html5/thumbnails/1.jpg)
Error detection
![Page 2: Error detection](https://reader036.vdocuments.mx/reader036/viewer/2022062310/568167ee550346895ddd5c76/html5/thumbnails/2.jpg)
Types of errors
• Digitizing errors– overshooting– undershooting– polygons do not close– missing data
![Page 3: Error detection](https://reader036.vdocuments.mx/reader036/viewer/2022062310/568167ee550346895ddd5c76/html5/thumbnails/3.jpg)
![Page 4: Error detection](https://reader036.vdocuments.mx/reader036/viewer/2022062310/568167ee550346895ddd5c76/html5/thumbnails/4.jpg)
An example of horrible digitizing!!!
Contour lines never cross!!
![Page 5: Error detection](https://reader036.vdocuments.mx/reader036/viewer/2022062310/568167ee550346895ddd5c76/html5/thumbnails/5.jpg)
“dangling” node
overshooting
![Page 6: Error detection](https://reader036.vdocuments.mx/reader036/viewer/2022062310/568167ee550346895ddd5c76/html5/thumbnails/6.jpg)
River digitizedin the wrong direction
![Page 7: Error detection](https://reader036.vdocuments.mx/reader036/viewer/2022062310/568167ee550346895ddd5c76/html5/thumbnails/7.jpg)
3500m
3900 m
Digitizing rivers in the wrong direction creates “canyon” -like features instead of river valleys
![Page 8: Error detection](https://reader036.vdocuments.mx/reader036/viewer/2022062310/568167ee550346895ddd5c76/html5/thumbnails/8.jpg)
Types of errors
• Location errors (x,y coordinates)• Edge matching (“seamless”)
![Page 9: Error detection](https://reader036.vdocuments.mx/reader036/viewer/2022062310/568167ee550346895ddd5c76/html5/thumbnails/9.jpg)