The CEDRA Corporation^TM
Bridging Engineering with GISTM
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Command of the Month Bulletin

To better serve its client base, The CEDRA Corporation, starting in January 2005, will be issuing on a monthly basis a publication titled the Command of The Month Bulletin. The Command of the Month Bulletin is e-mailed to our users and posted on our home page in the form of a .pdf file. Links to the various issues and a brief description of each issue, published to date, are available below. The objective of this publication is many-fold and includes the following:

• Inform users of new features introduced to the CEDRA-AVseries suite of software,
• Describe in detail certain commands which are felt of being of special interest to the general user community,
• Educate our users as to the full capabilities of our software,
• Present solutions to problems and special application conditions encountered by users, and/or
• Provide for a means of receiving from our users, requests for new additions, modifications and improvements to our software.

The CEDRA Corporation is continually improving and expanding its CEDRA-AVseries software. Over the past two years we have converted all of our software from the ArcView® GIS environment to first the ArcGIS® 8.x platform, and then recently to the ArcGIS 9.x environment. In keeping up with the latest releases of ESRI software, The CEDRA Corporation makes a concerted effort in maintaining and upgrading earlier versions of their software. So that enhancements made to the ArcGIS 9.x environment are implemented in the ArcView GIS 3.x and ArcGIS 8.x environments, whenever technically possible.

Aside from changes that may be required due to ESRI modifications to their ArcView GIS and ArcGIS software, additions and modifications to CEDRA software are made as a result of: (a) technology advances, (b) experiences in using the software in our own projects, and (c) requests that are submitted from our users. CEDRA users are encouraged to let us know of the need for special commands and tools which they would like to have incorporated so as to facilitate their work. Many of the featured commands described in the Command Of The Month Bulletin are a result of user requests.

In addition, from time to time we receive calls from users inquiring how our software can be used to address special application problem conditions that have been encountered in a project. The solution we provide, if it is felt of being of general user base interest, will be published in a Command of the Month bulletin.

Presented below are the Command of the Month bulletins which have been published:

2008

• January 2008 issue discusses the process of creating metes and bounds annotation by picking two points using the Dimension 5 tool [Metes/Bounds] within the CEDRA-Dimension-Tools toolbar. The two picks define an implied baseline, which can represent either a line or a curve. If a curve is to be processed, the user has the option of either: (a) explicitly entering a radius value, or (b) picking a point on the curve to have the command compute the radius. This issue is a follow-up to the May 2005 issue which discussed the process of creating metes and bounds annotation from one or more selected features (line and/or polygon features).
• February 2008 issue discusses the [CEDRA-Text-Tools] toolbar which enables the user to create new and edit existing annotation features. This issue discusses how existing annotation features can be centered and offset from implied baselines (two user picks), as well as, existing features. This issue also discusses how "straight" text strings can be converted into "curved" text strings which follow the path of a selected polyline feature.
• March 2008 issue discusses the [Update Geometry] command which enables the user to introduce and/or update geometric attributes within a feature layer. The geometric attributes that are updated within a feature layer's attribute table include: coordinates, length, direction and area. In addition to updating geometric attributes the [Update Geometry] command is able to delete features that contain null or empty geometries, as well as, change the graphic representation of a feature by using coordinate values that are stored in the layer's attribute table.
• April 2008 issue discusses the [Points at Line EPts] command which enables the user to find the point feature that is closest to each end point of one or more line features, after which, up to two attributes that are associated with the point feature can be transferred to the line feature. The line and point features that are processed can reside in several different layers. The command processes features from the layers that are active or selected at the time the command is invoked. Users involved with sewer or water modeling will find this command particularly useful in transferring a point's "node number" or OID to a line feature. Additionally, the user is able to create a report file containing a listing of the line features that do not have a point feature "close" to one of the end points of the line.

2007

• January 2007 issue discusses the process of assigning attributes to one or many features. The application and use of the [Edit Feature], [Sequential IDs] and [Assign Attribute] commands are described. These are extremely useful tools when it comes to maintaining attribute data.
• February 2007 issue discusses the [Area Calculation] command which enables a user to create a polygon given three sides (baseline, start side, end side) and a desired polygon area in terms of square feet (sm) or acres (ha).
• March 2007 issue discusses the available tools within the CEDRA-AVland software for performing the geometric layout of a horizontal alignment. Horizontal alignments can be used in the design of street centerlines, pipeline alignments and other types of utilities which are comprised of multiple line, curve and/or spiral features.
• April 2007 issue discusses the [Plot Cross Sections] command within the CEDRA-AVland software for plotting or visualizing Cross-Section Data Tables. Topics covered include the superimposing of multiple cross-section surfaces, generation of earthwork quantities and the assignment of cross-section attributes for customizing the "look" of a cross-section surface.
• May 2007 issue discusses the [Transfer Attribute] command which enables the user to transfer or copy an attribute from one feature to another based upon a spatial relationship such as point in polygon. Similar to a "spatial join", this command does not result in the creation of a new shapefile or featureclass, but rather, the user is able to: (a) modify the features in a specified layer, (b) highlight the features which satisfy the spatial relationshp, or (c) perform a and b above.
• June 2007 issue discusses the [Spline Curve] tool which enables the user to create spline curves and edit existing polyline features. This tool enables the user to create a spline curve through a variable number of keynodes using one of four curve generation methods. The available methods include: Circular Arcs, Natural Spline, Clamped Spline and Lagrangian Interpolation. In addition, the geometry of existing polyline features can be reshaped to match that of a spline curve as defined using this tool.
• July 2007 issue discusses the [I CV/LIN] and [I 2CV] tools which enable a user to intersect a curve with a line and a curve with another curve, respectively. This issue discusses the nuances of performing these types of intersections. Particularly important is how one can perform an intersection when an existing curve feature does not exist and how one controls which intersection is desired.
• August 2007 issue discusses the [Aliquot Polygon] command which enables the user to transcribe an Aliquot parcel/polygon description. This command enables the user to subdivide a quadrilateral by entering various quadrant identifiers such as NE, SE, N2NE, E2W2 and the like. As the identifiers are entered a red polygon graphic element is displayed reflecting the results of the subdivision. The user then has the option of converting the polygon graphic element into a polygon feature.
• September 2007 issue discusses the [Read Lease Nominations] and [Enter Lease Nominations] commands which enable the user to assign a value to one or more features which are described in terms of Aliquot descriptions. The user is able to specify which attribute (field) the value should be stored in, as well as, have the values read from an ASCII based file or entered via a multi-input dialog box.
• October 2007 issue discusses the Traverse File Format. Users who have the need to export polyline and/or polygon features using the Traverse File Format can use the [Export Generate] command to create one or multiple ASCII based files for a group of selected features. The Traverse File Format is a simplistic data structure which describes in surveying terms the courses comprising a feature. The format enables the user to easily verify the bearings, distances, radii, chord lengths, etc. which were used in creating a feature.
• November 2007 issue discusses the [Map Tips] tool within the CEDRA-DataEditor software. The [Map Tips] tool provides the user the ability to display a multi-line map tip. A map tip appears when the user moves the cursor over a specific feature and maintains the position. In so doing, the tool performs a feature search after which a map tip appears containing a list of attribute values. The attribute values which are displayed are user-specified and in addition contain a user-specified label to better identify the value being displayed.
• December 2007 issue discusses the [Copy Selected Features] command within the CEDRA-AVcad software. The [Copy Selected Features] command provides the user the ability to copy selected features from one or more layers into another layer. It also provides the ability to copy attribute (field) information, as well as, the ability to specify a field mapping file. The field mapping file can be used to map a field to one or more other fields, as well as, specify an attribute equation which can be evaluated to compute a value for storage. Attribute equations can contain mathematical operators (+, - , /, *, ^), intrinsic functions (SIN, COS, SQRT, ABS, TRIM, etc.) and conditionals (IF statements).

2006

• January 2006 issue discusses the process of developing a TIN and Contours from a set of random points containing x,y,z values, as well as, editing the TIN and regenerating new contours.
• February 2006 issue discusses how to Mirror and Repeat features using the Transformation tool. It also discusses the process of creating FeatureClasses and Datasets within a Personal GeoDatabase (PGD). It should be noted that the ability to mirror and repeat features brings the integration of CAD and GIS one step further.
• March 2006 issue discusses how to import an existing EPANET model into the CEDRA-AVwater software. It should be noted that the ability to import an EPANET model brings the integration of Engineering and GIS one step further.
• April 2006 issue discusses how to create various types of Callouts from within ArcMap. The tools found in the CEDRA-Callout-Tools toolbar provide similar functionality to the Callout tools found in the Text tools drop-down list found in the ArcView GIS environment.
• May 2006 issue discusses how to translate, scale and/or rotate features from within ArcMap or ArcView. Using the concept of an Existing Baseline Direction and a New Baseline Direction the Transformation tool can be used to perform a wide variety of transformations on selected features.
• June 2006 issue discusses how to modify the size, font, color, orientation and position of a group of selected annotation features using the Modify Annotation Features. In modifying the position of an annotation feature, the user is able to have the command determine an associate line for the annotation so that when the annotation is repositioned, it can be relocated in a manner which maintains its relationship to the associate line.
• July 2006 issue discusses the process of creating an overall sewer profile and "cutting-out" individual sheets for inclusion on Plan and Profile drawings. Using the CEDRA-AVsand software, this month's issue details the procedure in creating the geometry of a sewer model and the appropriate steps in generating profile sheets individually and in mass.
• August 2006 issue discusses the process of splitting a parcel using the [Parcel Split] command within the CEDRA-AVparcel software. Note that the split line used in the parcel splitting process can be comprised of multiple line and curve features, in addition to being a single polyline feature. Furthermore, it is possible for the split line to intersect the sides of the polygon being split, in addition to the case where the split line extends beyond the edges of the polygon.
• September 2006 issue discusses the process of combining a parcel using the [Parcel Combine] command within the CEDRA-AVparcel software. Note that if the polygon(s) which are to be combined with the base feature fall completely within the base feature, the user is able to create a "hole" or a doughnut shape.
• October 2006 issue discusses the process of annotating and updating data associated with a group of selected point features from one or more layers. Specifically, the bulletin describes how the user can create annotation for a point feature's point number, coordinates, elevation, point code and description. In addition, the bulletin describes the process of how to update in the point feature's attribute table its coordinate in terms of map units, distance units and/or latitudes and longitudes.
• November 2006 issue discusses an alternative to the DXF format, the Generate File Format. Users who have the need to develop customized applications using ArcGIS data can use the [Export Generate] command to create an ASCII based file containing geometric and/or attribute data for a group of selected features. The Generate File Format is a simplistic data structure which users can import for further manipulation and/or display. Reference is made to the October 2007 issue for an updated description of the [Export Generate] command.
• December 2006 issue provides a detailed description of the [Import Points] and [Connect Points] commands. These commands provide the user functionality for importing ASCII based files in a variety of file formats enabling the mass generation of point, line, curve, polygon and annotation features. The commands also provide functionality for generating lines by connecting existing points using one or two attributes which are associated with the points. The connectivities which are created can be based upon a sequential attribute or a sequential attribute in conjunction with a common attribute value, such as a point code. For those involved in post-processing survey data, this issue is a must read.

2005

• January 2005 issue discusses the operation and use of the CEDRA-DxfExport software for the application of creating DXF files.
• February 2005 issue discusses the operation and use of the CEDRA-DataEditor software for the application of entering and maintaining attribute data.
• March 2005 issue discusses the tools which can be used to reshape and maintain polyline and polygon features. Topological operations such as union, combining, intersection, difference, etc. are discussed.
• April 2005 issue discusses how a parcel or traverse can be defined, with or without a tie-line and how an adjustment using the Least Squares, Crandall, Transit or Compass methods can be performed.
• May 2005 issue discusses the operation and use of the various annotation tools present in the CEDRA software. This includes not only the ability to generate annotation for metes and bounds, but also, coordinate annotation (state plane, UTM, latitude and longitudes), as well as, annotation of attribute data.
• June 2005 issue discusses the operation and use of the Parcel and Traverse Course Entry Form in the definition and editing of parcels and/or traverses.
• July 2005 issue discusses how to use the Perform a Topological Operation tool and the Overlapping Polygons command to identify and correct adjacent polygons which overlap and/or have gaps. A very important issue for those involved in maintaining a topological polygon database.
• August 2005 issue discusses how to print a map from within ArcMap at any user-defined scale, with or without, a drawing sheet border.
• September 2005 issue discusses recent enhancements to the ArcGIS implementation of the software for manipulating annotation features, including curved text.
• October 2005 issue discusses the Trim Elements to Intersection and/or Introduce Fillet tool, which has recently been added to the CEDRA-Intersection-Tools toolbar for ArcGIS users. This is quite a handy tool for those users who need to create linear or circular fillets.
• November 2005 issue discusses the methodology employed by the CEDRA-AVland software to produce multiple plan and profile drawings in an automated fashion.
• December 2005 issue discusses the methodology employed by the CEDRA-AVland software to produce an original ground profile drawing including the generation of elevation annotation which is interpolated along the original ground profile surface.

For more information on CEDRA^TM software and services contact The CEDRA Corporation at 151 Sully's Trail - Suite 6, Pittsford, New York 14534, phone: 585-232-6998, fax: 585-262-2042 or Send E-mail to CEDRA: cedra@cedra.com

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