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Notes on LandView Installation Procedures
This Help article was written to supplement information contained in three Help files concerned with accessing LandView data and map files as written to a LAN or local drive. The LandView 6 National DVD provides background not only for copying files for the National release, but it similarly applies to installing files from LandView 6 on DVD, the 2-DVD (East/West) release of LandView 6. A LandView Help file, Network Installation of LandView, provides instructions for installation of either format on LAN servers. A third Help file, Alternate LandView Installations, provides instructions for installing data on a local drive.
For some users, problems arise when data cannot be installed exactly as described above.
LandView and MARPLOT are Independent Applications
LandView and MARPLOT are two independent applications that work together-one as a data management program and the other as a map viewer. Their executable files, landview6.exe and marplot.exe, are nested in the default LandView 6 installation directory, c:\lv6a. Either application can run independently of the other, but, for convenience, MARPLOT generally starts from a button at LandView Home1 . As independent applications, each has inherent characteristics governing their use. This is particularly evident in how each accesses its associated datasets.
On first use of LandView following initial installation, LandView wants to find its data files within the application directory. Not finding them, it calls an executable file, make_links.exe, which locates the datasets and creates a set of shortcuts to them within the application directory. It looks for the installation DVD which carries the volume name, LV6, and which contains a similarly named data directory, LV6. Finding this, shortcuts are written to each of its contained data files - this is the primary method for accessing LandView data.
If the installation DVD is not found, LandView searches the root level of all available drives for an LV6 directory. Finding this directory (and if it contains the appropriate datasets), the shortcut files point to this new directory. Generally, a search is in alphabetical order. If there is a user-mapped directory, H:\, and a LAN-administered directory, R:\, and each contains an LV6 directory, the H:\ directory would be found first, and the shortcuts would point to it.
This is not true for LandView data installed in an LV6 directory on the C:\ drive of a workstation or laptop. (It would be true, however, for this directory on an auxiliary drive, such as D:\.) If an LV6 directory was installed on c:\ alongside of a c:\lv6a directory, and LandView was directed to find a Census file, an error message would appear as follows2 :
On "OK", LandView would open a Browse screen. Once the States file was located in c:\lv6, LandView would create a complete set of data shortcuts.
As independent installation of LandView on a work station or laptop is common, we should comment additionally as follows: The LandView dataset can be copied to a companion LV6 directory on the C:\ drive and the error message can be dealt with as above. However, the LV6 data files can be copied directly to the c:\lv6a directory. If LandView finds its data files within the application directory, it ceases to search further, and no shortcut files are created.
Other LandView Data Options
Once LandView has written a valid set of shortcut files, it no longer searches for LV6 directories; it will access data files as directed by the shortcuts. If there is a valid LAN or local dataset installed and a LandView DVD is in the DVD drive, the DVD will be ignored in favor of previously established shortcuts. If it is desired to access an LV dataset other than the installed dataset, it is recommended that the current c:\lv6a be deleted and replaced by a clean install.
If a "clean" installation is not elected, the following could occur. Suppose LandView data was available from both a user-mapped directory, H:\, and a LAN Administrator-controlled directory, R:\, as stated above. LandView is currently directed to the user-mapped directory. If the mapped directory were made inactive for any reason and LandView was started, the following error message would appear:
On "OK", similar messages might repeat several times before LandView would reset itself and find the files on the R:\ drive or before it would open a browse window requiring the user to find states.lv6.
A variation of the above procedure can force LandView to find data files on other than a mapped drive. For example, LandView files could be created, as above, on a LAN in the previously mentioned LV6 Data directory, but not as a mapped drive. A clean install of LandView would not find available files at any expected location and would request the user to locate the states.lv6 file. Locating it at . . . \LV6 Data\LV6\states.lv6 would create the necessary shortcuts.
MARPLOT in LandView
To MARPLOT, data means maps. A map, as computer data, is a directory containing a MARPLOT-generated file, name.map. A map directory can contain data for a single map layer or multiple map layers, or it can contain none. It can be an empty container awaiting layer data from a user.
MARPLOT accesses maps in priority order as follows: All map directories nested in the same directory as the MARPLOT executable file, marplot.exe3, and at the same level as the executable file are immediately recognized by MARPLOT on startup. (Maps nested in sub-directories are not recognized.) When a map is identified with the Find New Map button, a path statement is written to MARPLOT, and such maps are also recognized on MARPLOT startup and continue to be recognized on subsequent startups as long as the file statements are valid. A third method is external instruction. For LandView, this is provided by an information file, marplot.vnx. It needs to be available to the MARPLOT application-normally at the root level of an available drive.
MARPLOT cannot contain two identically named maps. If MARPLOT finds a named map at priority one, above, it will display this map and ignore similarly named maps at priorities two or three.
All MARPLOT maps available with the LandView application are contained in Maps directories on LandView release DVDs. The maps are of two types - agency maps associated with LandView data and County TIGER/Line topological map files. Consult The LandView 6 National DVD for further details.
As there are more than 3,000 U. S. Counties, if MARPLOT had to follow its normal startup procedure and identify the contents of each map, startup would be interminable. Instead, MARPLOT accepts the content of each map-its containing layers and the number of objects on each layer - as stated in marplot.vnx and only verifies the path statement. However, if a map identified in the VNX file is not found, MARPLOT immediately stops reading the VNX file. Only those maps previously verified become available to MARPLOT!!
Unless otherwise instructed, MARPLOT looks for the VNX file at the root level of available drives, most normally at the same location as the MAPS directory copied from the DVD.
Let us examine the anatomy of a VNX file. Remember that this is a text file. You should not edit it with a word processor, such as MS Word, which can introduce coding other than simple text. Yet, editing the VNX file (and often other text files) can require some sophisticated processing tools. For Windows PC computers, the recommended text file processor is WordPad.
The first line of text, LV6, directs MARPLOT to the Installation DVD. As discussed in the associated Help files, MARPLOT needs to be redirected to the current location of its Maps directory, at the root level of an available drive.
Following that are a series of symbols that are shorthand for the names of layers contained on the various maps. Next, a line of text labeled "MAPS" signals the start of the map directories.
The first map is the Census map. Its path statement indicates that it is contained in a MAPS directory at the root level of the LV6 volume, and its map name is Census. Subsequent lines of text identify its contained layers, indicated by symbols. Four groups of numerals are coded latitude/longitude values identifying points on a rectangle bounding the objects on the layer. The final numerical set identifies the number of map objects contained on the layer.
The file continues through the contained agency maps until the first of the contained TIGER/Line map files is reached. Here, the path statement shows that the map is contained in a subdirectory, TIGER, nested in the MAPS directory. The map is nested further in another directory, AL, and it is named by its FIPS code as"01001". This identifies it as the first county alphabetically in Alabama. An independent text identifier further interprets this as Autauga County, Alabama. The VNX file continues until the last county in the last state, alphabetically, is identified.
Supporting Alternate Installations of LandView
There is an earlier MARPLOT map functionality still available that can be useful in problem installations. An example of this would be where all users could not map to an identical drive letter for a user-installed LAN directory. Another example could be providing a map set to match the example cited above when the LandView data files are not installed to a directory accessible as a mapped drive.
To employ this older map search functionality, proceed as follows:
In c:\lv6a, create a directory called CDmaps. Copy the marplot.vnx file to this directory, but do not also copy it to the location of the Maps directory. Change the file suffix, presently VNX, to TXT. Edit the first line of text to display the drive letter containing the Maps directory. MARPLOT, finding instructions at this location, will access the maps in the same manner as finding a marplot.vnx file at the root of an available drive.
For MARPLOT to find a Maps directory nested in a subdirectory of an available drive requires some additional effort, and here is where WordPad functionality is helpful. Notice above in the VNX file displayed as text that a complete path statement for any given map starts with the identified drive letter as the first line of text and continues for each map as, \maps\ . . . Using WordPad, we can edit the TXT file by replacing "\Maps", currently at the root of an available drive, with a more appropriate statement. Use WordPad/Edit/Replace similarly to that shown below and "Replace All".
For PC LandView, the LandView Executables need not be in c:\lv6a
While not generally recommended, it is possible to have two independent LandView directories on the same workstation or LAN. For example, both LandView East and LandView West could be available from the same computer. In this instance, it would be better for each installation to be in its own 'mapped' drive in directories identified as LandView East and LandView West.
Assume that LandView East is installed first. On completion of installation, a c:\lv6a directory is created and, on tracking to the mapped drive, a set of shortcut files are created in c:\lv6a. Rename this directory as LandView East. To complete installation, the LandView Desktop shortcut needs to be edited as below:
The procedure can now be repeated to create a similar Desktop icon, LandView West.
For these procedures to be successful, each MARPLOT application needs to be directed to its own set of map files. The VNX approach cannot be used. You must employ the CDmaps approach. An important warning. Do not run both applications concurrently, and, especially, close a first version of MARPLOT before opening the second. If the first version of MARPLOT is running and the second version of LandView is opened, the second LandView will track to the original MARPLOT instead of opening its own linked version.
Do You Use MARPLOT More Frequently than LandView?
A final installation mode should be considered. There are occasional users of LandView who are more frequently concerned with the topological map files for their Home County (emergency planners, etc.). These may wish to access LandView from the DVD yet more frequently visit the MARPLOT map. They can "Copy and Paste" their County map file (and possibly the files for adjacent collar counties) to c:\lv6a. Such users would be well advised to create a Desktop shortcut that will start MARPLOT independently.
1Some users may occasionally want to start MARPLOT as an independent application. MARPLOT can be started from a shortcut to marplot.exe placed on the Desktop.
Back 2Similarly, if an EPA or GNIS file was attempted to be accessed, the dialogue would request pointing to an appropriate EPA or GNIS file. Back 3For MARPLOT as used with LandView, this is the c:\lv6a directory. Back