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ArcView Avenue Script
‘simple script to place a 5m diameter circle at selected
‘used for GPS data interpretation scale circles
‘to use, create a tool for this in the view
‘steve robertson, 2000 (email@example.com)
‘get cursor position in active view
curView = av.GetActiveDoc
curDisplay = curView.GetDisplay
userPoint = curDisplay.ReturnUserPoint
‘build the circle
activeCircle = Circle.Make(userPoint,2.5)
‘change for different diameter
graphicCircle = GraphicShape.Make(activeCircle)
aSymbol = BasicPen.Make
‘change for different colour
‘place the circle at cursor
curGraphics = curView.GetGraphics
5.9.2 Editing GPS Data Using the Data Dictionary
Tool Extension for ArcView
The Data Dictionary Tool Extension was developed for the post-
processing of GPS data and the creation of new data from different
mapping sources. The extension is intended for use for the creation of a
new stream line theme from GPS data and point themes from
documentation or other point themes. This document provides
instructions in the use of the extension tool. Users should have basic
ESRI ArcView or ArcINFO experience.
Current SHIM methodologies involve the use of differential GPS to collect
and store spatially accurate information on line, point and polygon
features of watercourses. Correct interpretation of the raw GPS inventory
data involves a series of post-processing steps that may be undertaken
within a variety of computer software packages. To simplify this process
and to allow SHIM mappers to more easily interpret their collected
stream information, the Data Dictionary Tool was developed as a
customized ArcView extension for post-processing raw GPS inventory
data. The Data Dictionary Tool also contains a series of features for
easily creating, editing and merging ArcView shape files that will assist in
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minimizing project size and will facilitate map data management. In
addition, there exists a wealth of historic SHIM data collected prior to the
widespread use of the Trimble GPS units. The Data Dictionary Tool was
developed to provide a means for linking this archived SHIM point data to
newly derived stream linework collected in accordance with current GPS
standards for spatial accuracy. In summary, the Data Dictionary Tool
Extension provides a means to: 1) manually correct stream linework
derived from GPS datapoints, 2) link previously derived GPS point data to
new stream linework using unique ids, 3) create and merge common
shapefile themes, 4) incorporate archived hard copy or electronic
spreadsheet data into current SHIM data formats, and 5) create digitized
polygons of riparian habitat. This guide will provide step-by-step
instructions in the application of the Data Dictionary Tool and is designed
for the basic ArcView user.
Loading the extension in ArcView
ɷ Copy the ddtool.avx file provided into
the Ext32 subfolder on your computer
ɷ Open ArcView with a new project and
in the project file menu go to File >
Extensions, select the Data Dictionary
Tool 1.0 extension and click OK.
ɷ Loading the extension will add new
script, view and dialog documents to the project. In the
project window select the views document and open the Edit
View by double-clicking on it.
Edit View contains all the tools for manipulating GPS derived data and creating
new point and line themes. There are also tools for linking and merging themes
with the same feature type.
Creating a new interpolated stream line
1. In the Edit View window’s button menu click on the Add Theme tool and
add a GPS derived line theme (e.g., streamdy.shp) to the view.
2. Click on the Interpolate GPS Line tool and a dialog will appear. Provide a
name for the new stream line theme and click OK.
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3. Another dialog box will appear prompting for the GPS derived line theme in
the Edit View to copy attributes from. Select the appropriate theme (e.g.,
streamdy.shp) and click OK.
1. The Line Edit Tool will appear and the GPS derived line theme will now be
colour coded based upon existing segment breaks.
5. Click on the Draw Circle Buffer tool and click on locations in the view
window to draw a series of 5m diameter red circles along the stream length.
Use the Zoom In/Out tools within the Edit View window to zoom
down to a view of the stream at which you can clearly delineate the
boundaries of the buffer circles. These buffers will assist in the determination
of the line of best fit during the line drawing process. A recommended
suggestion would be that 300-500 meters of stream be visible within a single
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screen view (approximate scale of 1:2500) to ensure accurate interpolation of
the stream line.
6. Click on the Draw Line tool and digitize a new best fit line theme
based on the GPS derived line and circle buffers.
7. Click on the Split Line tool to insert the segment break points or
vertices in the new line theme.
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8. After all segment breaks are accounted for, click on the Copy Attributes tool
to copy the original attribute data from a GPS derived line segment. Then
click on the Paste Attributes tool to paste the copied attribute data to a
new line theme segment.
9. Continue copying and pasting line segment by line segment. When all
attributes have been copied fully to the new line theme, click on the Save
button to save all edits.
Linking point data to a stream line theme
1. Ensure that a stream line theme and at least one point theme exists in the
Edit View window.
2. In the Edit View window’s button menu click on the Link Themes tool
to create a unique ID based on the stream name and TRIM mapsheet number.
3. In the Add Index Theme dialog that appears, browse to where the provided
index theme (trimgridp.shp) is located and click OK. This dialog appears only
when the Link Themes tool is used for the first time.
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4. In the Select Line Theme dialog that appears, select the appropriate line
theme for linking and click OK. A new field named “Key_ID” will be created in
the line theme.
5. In the Select Point Theme(s) dialog that appears, select the appropriate point
theme(s) for linking and click OK. A new field named “Key_ID” will be created
in the point theme(s).
6. In the Stream Name dialog that appears, use the default name or enter a new
name for the stream to be used in the unique ID and click OK. The stream
name “test” is used as the default.
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Another dialog will appear displaying the unique ID and prompting the user
for validity. Click YES to continue. If the unique ID exists already (e.g., line
theme already contains a different unique ID) a dialog will appear prompting
for either the use of the existing ID or replacing it with the new one. The
default is NO.
Merging themes together
1. In order to use the Merge Themes tool more than one theme of the
same feature type must exist in the Edit View window.
2. Click on the Merge Themes tool in the Edit View’s button menu. In the Input
Theme dialog that appears, select one theme to be used as the template for
the creation of fields. That means a field not contained in the template will
not be merged into the resulting theme.
3. The Themes to Merge with… dialog box will appear showing themes in the
view window that are of the same feature type. Select the appropriate themes
and click OK. Another dialog box will appear prompting for the name and
location of the newly merged theme. Enter the appropriate information and
click OK. The merged theme will be automatically added to the Edit View
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Creating or updating SHIM data points
The SHIM data entry options included with the Data Dictionary Tool extension
can be used for recording and mapping of new point data. In general, however,
this information is now more reliably collected and recorded directly in the field
using high-end GPS receiver units and associated data loggers. The primary role
of the SHIM tool is instead to allow incorporation of data from other sources
(e.g., archived hard copy documents) into formats compatible with existing SHIM
data structure and spatial mapping. A different tool dialog box can be brought
up for each of the different point data types (e.g., culverts, cross-sections,
obstructions, etc.) for which SHIM information is currently collected. Data entry
options within each data type are identical to those currently existing within the
SHIM Data Dictionary (Version 23) that has been developed for use with the
Trimble Pathfinder GPS. The only exception to this relates to the normal SHIM
entries for riparian bands; due to size limitations a tool for riparian bands has
been excluded from this extension.
1. In the Edit View window’s file menu go to SHIM Data and select the desired
SHIM data tool to create your new points.
2. A Point Tool dialog box will appear indicating the required cells for data
entry. Enter the appropriate information in each cell. Then click on the Add
Point Tool and place the accompanying cross-hairs on an
selected area of your view (e.g., correct location on a mapped stream) to
create a new point feature with its associated attribute data.
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3. After entering the required information and creating a new point, click on the
Save As button to save the point as a new shape file. This will
automatically add the file to the Edit View window.
4. After creating single shape files for each point of the same data type (e.g.,
individual erosion points), all the saved points should be merged together
into a single theme (e.g., pooled erosion points theme). To do this use the
Merge Theme tool and associated methods outlined in section D.
5. To link the newly created SHIM data points to a mapped stream line use the
Link Theme tool and associated methods outlined in section C.
Creating riparian polygons
The SHIM Data extension can also be used to delineate riparian habitat polygons
adjacent to mapped streams. Data cells within the Riparian Polygon Tool can be
populated by habitat information collected directly in the field or else interpreted
from photogrammetric analysis of underlying orthophotos. The Confidence data
cell allows for a qualitative assessment (low, medium or high) by the user of the
relative accuracy of the riparian classifications for the polygon.
1. In the Edit View window’s file menu go to SHIM Data and select the Riparian
Polygon tool to create your new habitat polygons.
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2. The Riparian Polygon Tool dialog box will appear indicating the required cells
for data entry. Enter the appropriate information in each cell.
3. Then click on the Add Polygon Tool and use the accompanying
cross-hairs to create the lines and vertices of the habitat zones you wish to
define within the selected area of your view. The process will create a new
polygon feature with all its associated attribute data. If available, it is
recommended that an underlying orthophoto image of the area be imported
into your ArcView project. This will greatly enhance the ability to accurately
delineate the boundaries of riparian habitats. Acquisition of current
orthophoto coverages is the responsibility of the user, and can be obtained
through various regulatory agencies (e.g., FOC, GDBC, municipal
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