1. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 KEEP THIS TEXT BOX this slide includes some ESRI fonts. when you save this presentation, use File > Save As > Tools (upper right) > Save Options > Embed TrueType Fonts (all characters) this will allow vector maps created with common ESRI symbols to show on computers that do not have ESRI software loaded a a a a a a ESRM 250/CFR 520 Autumn 2009 Phil Hurvitz Creating Feature Datasets (vector data) 2

2. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Digitizing Creating vector data sets Converting to feature class Creating new datasets Snapping Altering the shape of lines and polygons Splitting features Unioning polygons Merging polygons Intersecting polygons Clipping polygons Adding attributes Undoing edits Saving edits Overview

3. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 most common “legacy” method of getting data into a GIS Digitizing tedious & detail- oriented work

4. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 How the digitizing tablet works Digitizing tablet operator clicks on or traces features y = 10 x = 5 coordinates are placed in database

5. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 ArcGIS supports creation & editing of vector data sets (shapefile & geodatabase = “feature class”)  Point  Line  Polygon Data sets are completely editable  Coordinate data  Attribute data Creating vector data sets

6. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Any supported vector data set can be converted to feature class Converting to feature class CAD data

7. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Any supported vector data set can be converted to feature class Converting to feature class shapefile or gdb feature class

8. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Selected sets are converted Converting to feature class

9. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 New datasets can be created from scratch in ArcCatalog  decide in advance what feature type to represent the data Creating new datasets select feature type

10. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 New datasets can be created from scratch in ArcCatalog  specify coordinate system Creating new datasets

11. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Creating new datasets: “heads-up” digitizing Done completely on computer (no digitizing tablet), hence the term “heads-up”

12. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Create a road layer using a photo background Creating new datasets

13. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 New features can be created from tracing existing selected features Creating new datasets

14. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Snapping controls:  how features align during creation/editing  connections of lines (node placement)  completion of polygons  avoid overshoots/undershoots  avoid slivers or gaps Snapping

15. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Snapping behavior controlled by the Snapping Environment dialog Snapping

16. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Snapping

17. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Interactive snapping options  Snap to an existing vertex  Snap to an existing line segment or polygon edge  Snap to an intersection of two or more lines  Snap to an existing line endpoint  Snapping can be layer-to-layer Snapping options

18. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Snapping Helps avoid these errors J. Lawler

19. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Topological editing: shared edges are all affected by edits Altering the shape of lines and polygons

20. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Non-topological editing: only a single feature is edited Altering the shape of lines and polygons

21. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Polygons are split by a user-defined line Splitting (cutting) polygons

22. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Lines are split at a specified location Splitting lines

23. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Geodatabase splitting policies Attributes are handled by policies  Duplicate: values in new records are copied from the parent record  Geometry property (e.g., area, perimeter, length) automatically handled  Geometry ratio  based on geometry (e.g., percent of area) Splitting features

24. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Attribute splitting (for geodatabase feature classes) is handled by policies Splitting features image from ESRI

25. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Merging polygons select multiple polygons from the same layer original polygons are merged into a single new polygon

26. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Attributes are handled by rules in the same way as splitting Merging polygons image from ESRI

27. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Merging polygons: an example Merging polygons J. Lawler

28. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Similar to merge, but can combine features from > 1 layer Unioning polygons

29. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Intersecting polygons spatial area as the "set" for intersection a new polygon from common areas like mathematical intersection

30. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Clipping polygons Option 1: discard the intersection

31. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Clipping polygons Option 2: keep only the intersection

32. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Clipping: an example J. Lawler

33. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Clipping: an example J. Lawler

34. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Landscape metrics calculated from clipped frog home range % forest 73 % ag12 Ag dist20 F-patch.s60 A-patch.s6 Clipping: an example J. Lawler

35. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Attributes need to be defined for new datasets  Fields are added; define  field name  data type  width  decimal precision Adding attributes

36. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Adding & defining fields: note field names & data types Adding attributes

37. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 After fields are added, attributes can be updated Adding attributes

38. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Edits can be undone in reverse order Edits can be undone up to the previous save (or creation) Once a dataset’s changes are saved, edits cannot be undone It can be good to have a backup of the data created before an editing session Undoing edits

39. ESRM 250 & CFR 520: Introduction to GIS © Phil Hurvitz, 1999-2009 Save EARLY and OFTEN You are prompted to save edits when:  Dataset is closed for editing  Another dataset is opened for editing  Document is saved or closed  ArcGIS is closed Saving edits