CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt1 Overview Digitizing Creating vector data sets Converting to shapefile Creating new themes Snapping Altering the shape of lines and polygons Splitting features Unioning polygons Combining polygons Intersecting polygons Subtracting polygons Adding attributes Undoing edits Saving edits_

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt2 Digitizing most common “legacy” method of getting data into a GIS tedious & detail-oriented work

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt3 Creating vector data sets ArcView supports creation of vector data sets Point Line Polygon Complete creation & editing of data sets is supported Coordinate data Attribute data

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt4 Converting to shapefile Any supported vector data set can be converted to shapefile

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt5 Converting to shapefile Selected sets are converted

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt6 Creating new themes New themes can be created from scratch

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt7 Snapping general snap tolerance interactive snap tolerance

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt8 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

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt9 Altering the shape of lines and polygons

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt10 Splitting features Coordinate features (lines & polygons) are split Attributes are handled by rules Blank: values in new records are left blank Copy: values in new records are copied from the parent record Proportion: numeric values are proportional to the original area or length Shape Area: values are the areas of the new polygons Shape Perimeter: values are the perimeters of the new polygons Shape Length: values are the lengths of the new lines

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt11 Splitting polygons

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt12 delete erroneous lines select erroneous lines split the line create a line Splitting lines

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt13 Unioning polygons Multiple features are merged into oneAttributes are handled by rules

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt14 Unioning polygons

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt15 Combining polygons

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt16 Combining polygons

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt17 Intersecting polygons

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt18 Subtracting polygons

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt19 Adding attributes

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt20 Undoing edits Edits are undone in reverse order Edits can be undone until the last save (or creation) Once a theme’s changes are saved, edits cannot be undone

CFR 250/590 Introduction to GIS, Autumn 1999 Creating Shapefiles & Vector Editing © Phil Hurvitz, create_f_themes.ppt21 Saving edits Save EARLY and OFTEN Edits are saved when: Theme is closed for editing Another theme is opened for editing Project is saved or closed ArcView is closed