Chapter 11 Basic Editing in ArcMap

Objectives Understanding the basic editing process Using snapping to ensure topological integrity of features Adding features to map layers Using the sketch tools and context menus for detailed and precise location of features Entering and editing attribute data

What can you edit? ArcView –Shapefiles and geodatabase feature classes ArcEditor and ArcInfo –Geodatabase networks –Geodatabase topologic features –ArcInfo coverages (not recommended)

The Editing Toolbar Menu Select Sketch toolTarget Split Rotate Shared edit Attributes Taskbar

Snapping A dangle—the two lines fail to connect Correct topology—the horizontal line intersects the vertical one, creating three lines. node Automatically connects features

Snap distance a c b a c b Features that fall inside snap distance are automatically connected to each other.

Types of snapping End snapping Edge snapping Vertex snapping ? Snap distance

Setting snapping

Editing features The select tool, sketch tool, and task bar work together when editing Select tool Sketch tool

Target Layer Controls which layer new features will be placed in.

Creating a feature Double-click to finish sketch

Editing context menus Vertex menu Sketch menu Right-click on sketch Right-click off sketch

Sketch menu options 0 Enter absolute point Enter change in xy Constrain angle Constrain length

More options Deflect from sketch Parallel to feature Deflect from feature Bearing and distance

Adjacent polygons gap Topological errors between two polygons Coincident boundary between two polygons overlap

Creating adjacent polygons Draw first polygon with Create New Task Add new polygon with AutoComplete Two polygons with coincident boundary.

More tricks Multipart features Perpendicular edge snapping

More sketch tools DistanceArc tool Intersection Trace tool

Modifying a feature Click and drag vertices Sketch keeps track of new figure shape Double-click when finished

Rotating features Select feature Rotate tool Drag around rotation point Click and drag to move rotation point

Splitting polygons Select polygon to split Sketch new boundary Double-click to finish sketch and create polygons

Attribute Editor Selected features Edit all selected Edit single feature Explore features

Saving work Save early, save often!!! Stops editing and asks to save any unsaved edits Saves and continues editing

Coordinate systems ArcMap can edit across coordinate systems –Edited coordinates always saved to source file coordinate system regardless of data frame coordinate system Projecting on-the-fly may degrade performance –Avoid it when possible

TIPS Always have a backup copy Shapefiles simplest and most robust Keep number of open files down Try to keep layers in same coordinate system Save frequently!!!!!