Archive for the ‘XMap Q&A’ Category

XMap Q & A

November 10, 2008

What is the function of the Magic Wand Selection tool in the XMap toolbar? It is always grayed out, even after I make a layer active.

The Magic Wand Selection tool was added to XMap for some very specific applications and it requires that several prerequisites are satisfied before it becomes available. 

The object of the tool is to allow the concurrent selection of multiple line segments that are connected and share a common attribute. This provides the means to verify that the particular attribute has been consistently assigned for each selected segment and to ensure that the line segments are actually connected without any breaks. It also simplifies the process of editing attributes as all sections of the line can be updated simultaneously.

The Magic Wand Tool is essential for DeLorme’s corporate road and street data management process. Technicians are able to quickly ascertain whether roads, which are typically represented in the database by many individual line segments, are connected and that each segment has the correct road label. DeLorme software depends on this verification of connectivity and label consistency to ensure that the route planning tool provides the optimal directions and to guarantee that address searches return accurate results.

magic_wand1While not every XMap user will find a need for the Magic Wand Selection function, several innovative applications have recently been brought to our attention. These include an energy company using the tool to manage gas pipeline maintenance schedules, and a public works department monitoring water supply lines.

In order to perform a Magic Wand Selection, the geometry shape of the line layer must be changed to topological using the Layer Properties dialog box. This exposes the nodes that represent the connectivity relationship between intersecting and adjacent line segments. A User Input query must then be created based on the attribute which is common to each segment. After these modifications have been made and the layer is made active in the drop down list in the toolbar, the Magic Wand Selection tool will be available.

The following procedure is an example of the practical use of the Magic Wand Selection tool in XMap using a layer containing bus routes served by the Washington DC Metropolitan Transit Authority. In this case, the Magic Wand tool will allow us to quickly see the roads and streets served by each numbered route. To follow along with these steps, download the shapefile named Metro Bus Routes from the DC GIS Data Clearinghouse at http://dcatlas.dcgis.dc.gov/catalog.

 

  1. After importing the metro bus routes shapefile, use the Symbolize tool to select your preferred color and style for the lines. In this case a layer classification is not necessary.
  2. Right-click on the layer in the workspace and choose Properties.
  3. From the Geometry Shape drop down list, choose Topological Geometry and uncheck the boxes next to Shape Points and End Nodes. This setting will disable or turn off all of the nodes, which are not needed for this application, thus ensuring that the map is uncluttered.
  4. Click the Query button on the left of the tab area and ensure that the Metro Bus Routes layer is selected in the Layer drop down list.
  5. Build a query using the following parameters:
    • Attribute – LINENAME
    • Operator – EQUALS
    • Criteria – [Leave Blank]
    • Logical Operator – [Leave Blank]
    • User Input – Check Box
  6. Give the query a name, such as “Search by Route”, by clicking the Manage button and selecting Rename.
  7. In the toolbar above the map window, select Metro Bus Routes from the Active Layer drop down list.
  8. magic_wand2Click the arrow on the Magic Wand Selection button and select the query that was just created
  9. Use the tool to select a line segment on the map. The entire route will be highlighted, indicating the directions followed by that particular bus route. Furthermore the attributes for this route will be highlighted below the map. To filter this list so that only the results of the Magic Wand Selection are displayed, choose Toolbar Select from the Show drop down list above the attributes table.

The Magic Wand Selection tool is further example of DeLorme’s commitment to developing innovative and practical spatial technology that is accessible to all.

I am currently using the 5.2 version of XMap GIS Editor, should I upgrade to XMap 6?

September 25, 2008

 Over recent weeks, DeLorme professional sales staff has been asked this question more than any other. While most of the significant enhancements in XMap 6 have been made to the Enterprise edition, specifically to the data access and distribution tools, there are numerous updates to the core mapping functionality that offer enough reason to upgrade. These include:

  • The option to append or replace data when importing. This allows you to maintain the structure of a GIS layer (for example, classification schemes, symbolization, and queries) while adding new objects or replacing objects from an external data source
  • Improved handling of large layers
  • Multi-point image registration, which was previously available in only the Enterprise edition of XMap
  • More efficient file and data management with the DeLorme Docs folder moved to My Documents
  • Phone data for use in XMap’s Phone tab is now included at no additional cost
  • NavMode for improved in-vehicle GPS navigation
  • And much more 

 

 

 

 

 

 

The release of XMap 6 constitutes a new approach to the ongoing evolution of DeLorme’s professional software. The XMap development team is committed to providing quarterly updates to XMap 6 that will be free of charge for all XMap 6 users. In effect, if you decide to upgrade to the current release version of XMap 6, you will receive each new edition of the software with significant functional improvements up until the release of XMap 7.

XMap Q & A for August 2008

August 7, 2008

 I noticed that you have Public Land Survey Data for most of the country; do you plan to add the Texas Public Land Survey data to this list?

The Texas Public Land Survey is distinct from the Public Land Survey System that covers most of the rest of the U.S. and was originally designed as a hybrid of the PLSS and the Spanish land grants system. While PLSS data can often be downloaded for free from various federal and state agencies, the Texas data is not as readily available.

DeLorme recently entered into an agreement with the Railroad Commission of Texas, a state agency that regulates the energy and utility sectors and that provides a variety of datasets for these industries. Through this agreement DeLorme will make available several GIS layers preformatted in XMap openspace format. These include oil and gas pipelines, well locations, and Public Survey polygons.

The Public Survey data is available for use in any edition of XMap 5.* or 6 and includes clearly defined boundaries and labels. Users of XMap Professional cannot change the color of the polygons, the style of the label, or any of the other characteristics of the layer; however, users of either the GIS Editor or Enterprise versions of XMap can modify the layer in numerous ways. For instance, the polygon color can be changed, the labels can be removed or edited, additional queries can be built, and selected areas within the layer can be highlighted and used to create a new layer. For details on how to perform any of these functions, refer to the Help system in XMap. 

For more information visit http://www.rrc.state.tx.us/

XMap Q & A: Can I overlay roads or GIS data on an aerial image on my PN-20?

May 21, 2008

PN-20 Snapshot 1In short, yes you can. Since it was first released almost two years ago, the Earthmate GPS PN-20 has been periodically updated and enhanced. While the device itself has remained the same, the firmware, or internal programming that determines how the device functions, has been revised and new versions have been released several times. Each firmware update improves the performance of the device, upgrades the existing functionality, and often adds new features and functions. Running the firmware updater is like trading in your old PN-20 for the latest model. If only trading in your car was that simple.

The most recent firmware update (version 1.4) was released in mid-April, 2008 and offers a number of significant enhancements for PN-20 users. Perhaps the most noteworthy, especially for XMap users, is the option to display hybrid maps, meaning that both raster and vector data layers can be displayed simultaneously. For instance, you can now view an aerial image on the PN-20 screen and overlay OpenSpace GIS data layers, which can be independently turned on or off as needed. This function also provides the means to display the roads and streets from the USA Topographic Data on top of an image.

 To display a hybrid map on the PN-20, follow these steps:

  • In XMap, create the required map package or packages containing the imagery, road network, GIS data, or any other features. Note that multiple data types can be combined in a single map package however you might find it easier to manage your multiple data types by creating a unique package for each type of map layer.
  • Transfer the saved packages to the device using the Exchange wizard in XMap. For larger files, it is recommended that transfer the map packages to the external SD card using a dedicated SD card reader.
  • After the transfer of data is complete, click the Page button on the device until the map screen is displayed.
  • Press the Menu button and select Map Setup
  • The first item on the list is Data Layering. This provides the tools for enabling or disabling a particular type of data and for adjusting the layering sequence. The type of data appears at the top of the list will be topmost layer on the map. To create a hybrid map, ensure that both the image and the appropriate vector data are visible and that the image or raster layer is on top.
  • PN-20 snapshot 2Press the Quit button to return to the Map Setup list and scroll down to Data Management. This list displays all of the map packages that have been transferred to the PN-20’s internal memory or SD card. If you combined several data types into one map package, then you may see only one item listed. On the other hand, if you created different map package for each data type, these will be individually listed and can be independently controlled. Make sure that the map package or packages containing the imagery and the vector data are visible.
  • Press the Quit button and continue to scroll down the Map Setup list until you see the Show Hybrid Maps option, which will be turned off by default. Select the check box to enable this feature.
  • Finally, press the Quit button again to return to the map view. All active line and point objects such as roads, rivers, borders, draw objects, or OpenSpace GIS data will appear on top of the image. Note that the display of polygons such as lakes, parks, or OpenSpace polygon layers is not supported using the hybrid map option.

 For more information on creating map packages and transferring data to and from the PN-20, refer to the documentation that was included with the device. To check the firmware edition on your PN-20, press the Menu button, select Device Setup and scroll down to About this Device. For a list of firmware enhancements and to download the latest release, click here or check the NetLink tab in XMap for the latest available downloads.

XMap Q & A

April 14, 2008

How do I use field-collected data to create a GIS layer?

When DeLorme’s long-awaited handheld GPS receiver, the Earthmate PN-20, was released over a year ago, we couldn’t have anticipated the level of interest that the device would garner among XMap users. With the release of XMap 5.2, which offered support for the PN-20, professional users were quick to recognize the value of being able to transfer any map, GIS layer, or aerial image to a gadget that they could easily carry in their pocket.

As with most other handheld GPS receivers, the PN-20 also offers a low-cost method for collecting data in the field. This data can be in the form of location points, typically referred to as waypoints, or lines, which record the movement of the device and are referred to as tracks.

 The Exchange function of XMap allows waypoints and tracks to be downloaded and displayed on the map. Waypoint and track layers are managed using the Draw tab tools, which include the option to change the appearance or symbolization of the objects as needed.

 More often than not, these field-recorded locations represent more than just points or lines on the map; they usually denote the location to which an array of data or information is attributed. For instance, a point might represent a nesting site to which such data as species, nest condition, number of eggs, etc. is assigned.

 In order to carry out this type of data mapping, the collected points or lines must be converted into GIS layers using XMap GIS Editor or Enterprise. The conversion process is very straightforward:

 

  •  First click the File button in the Draw tab and select the appropriate layer.
  • To the right of the tab area click the Copy To button and choose GIS Layer. This opens the GIS Import Layer dialog box with the selected waypoint or track layer automatically added as the source file.
  • Select a target database and click the Next button to begin the import process. The new layer will appear in the Workspace of the GIS tab.

Several attribute fields are automatically added to GIS layers that are created from data in the Draw tab. These include the label that was previously assigned, the type of symbol used to denote each object in the original draw layer and the date and time at which each object was created. Any or all of these attribute fields can be removed or deleted if needed.

The benefit of migrating field-collected data from their original draw layer format to the GIS tab is that additional data can now be added to each object. Attribute fields can created manually and the relevant data can be entered for each object in the layer. Alternatively, external data in the form of a spreadsheet, database file (.dbf), or several other formats can be imported and appended to the objects in the layer to automatically create additional attribute fields. These two functions are accessed by clicking Attributes button on the left of the GIS tab, clicking the Design View button at the upper left corner of the attributes table and clicking the Options button.

With the appropriate attributes added to each field-collected point or line, the data analysis tools of the GIS tab, such as the classification and querying tools, can now be employed to expose the spatial patterns in the data.

While the Draw tab in XMap provides an adequate level of functionality for simply representing a field-collected point or line on the map, you should consider using GIS tab to efficiently manage the data behind each point or line. Transferring data to the GIS tab is a simple as a couple of clicks of the mouse

Where can I find data to import into XMap?

March 10, 2008

If you have visited the XMap Web site, you should have seen a selection of screenshots that were created for the purpose of illustrating a diverse variety of applications for the software. While these screenshots include examples of some of the datasets that DeLorme offers for use with XMap, the majority focus on data that was either developed using XMap’s data creation tools or that was integrated from third-party data sources. A commonly asked question is, “From where does this third-party data originate?”

eagle_nests.jpgThere are countless sources of spatial data in both vector and raster format, much of which can be freely downloaded from local, state, regional, or national government Web sites or sometimes from educational institutions. Try typing “GIS Data” followed by a geographic area of interest into a Web search tool and you will often uncover libraries of data that will meet your needs.

For instance, here in Maine, the state-level GeoLibrary Board maintains and distributes almost 150 different data layers in vector format — everything from hospital locations to eagle nesting sites. Depending on the type of data, shapefiles can be downloaded for selected municipal areas, by USGS quad, or for the entire state. The site also offers recent high-resolution orthoimagery in MrSID format that can be used as a base map for your XMap projects.

Virtually all 50 states as well as the District of Columbia (which has one of the more extensive lists of data layers) have a GIS data repository where you can browse and download data layers. To help in your search, DeLorme is in the process of developing a data resources page that will provide a thorough list of agencies and organizations that offer spatial data. To begin with, we have pulled together a list of state-level data libraries to which we will eventually add other GIS data sources.

If you know of a data resource page that should be added to the list, please e-mail the details to prosales@delorme.com