Latest Contributions by MelitaKennedy

A couple of reasons for large vertex counts-- 1. Part of the boundary follows a water feature 2. Even long, "straight" lines shouldn't be only two point lines if you want to reproject the features. ArcGIS doesn't densify data as it reprojects the features. Straight lines may be curves in the new coordinate system. Melita ... View more

Please see response on gis.stackexchange.com. ... View more

Hi, Yes, you have a lot of questions that have long answers! First, have you tried reading the map projections guide book in the help? There are several topics each on geographic and projected coordinate systems. Geographic coordinate system: provides a frame work / reference system for locating positions on a spheroid or ellipsoid. Positions are located using angles and angular units. "Earth model". When displayed in 2D, it's actually projected using something like the Plate Carree map projection. Projected coordinate system: Two-dimensional framework / reference system for location positions. Includes a GCS as part of its definition. Has to distort data to crush the 3D surface into 2D: distance, shape, area using a map projection and parameters customized for a particular area. NAD 83 / NAD 1983 / North American Datum 1983: a GCS built using data from Canada, US, ?and Mexico? Finished in 1986 before GPS really got going, there have re-adjustments since in both Canada and the US. Canada: CSRS. US: HPGN / HARN, NSRS2007, and 2011. UTM: Universal Transverse Mercator. A grid system designed by the military. It's divided into 6 degree wide zones (there are a few exceptions) and covers the entire world. The map projection is transverse Mercator, with similar parameter values for each zone. The poles have separate UPS zones that use the stereographic projection. Can be used with any GCS, although the military uses WGS84 almost exclusively. DMS is a string format, not a double value. You can store only one value per double precision field, but can certainly add two fields to a table! You may need to set the data frame to a geographic coordinate system first. Also check out the Convert Coordinate Notation tool. Melita ... View more

Hi Ali, This isn't my area, so I'm just going by what I can find in the help and blogs. It looks like if you're in the US, you can download the API/SDK from the Customer Care Portal. If you're outside the US, then you have to talk to your local distributor. For instance, ArcGIS for Windows Mobile 3.1 released. Melita ... View more

Do you mean one of these: http://www.esri.com/apps/products/download/index.cfm?fuseaction=download.all#ArcGIS_Runtime_SDK_for_Windows_Phone ... View more

I don't know if there's a tutorial. The Create Fishnet tool is a little complicated possibly because it's modeled after the similar command in ArcInfo workstation. There's a decent topic that has some pictures of what happens if you set a rotation for example. How Create Fishnet works You can build the fishnet in any coordinate system. Sometimes it's easier to build a lat/lon one while at other times, it's easier to build one based on the coordinate values of a projected coordinate system (like UTM). You need to have the spatial extent and  the "cell size" or distance between grid lines. Alternatively, you can have a lower left corner plus how many 'rows' and 'columns' you want. If you have the later, the tool will figure out the separation distance for you. Note: If I remember correctly, the dataset created by the tool won't have a defined coordinate system, so you'll want to do that first with the Define Projection Tool. Melita ... View more

That's what I wasn't sure about. If everything needs to be reversed, then you'll probably have to do it via print driver. If you only need the geographic data reversed, you could try the Krovak projection. It was originally designed in the early 20th century for Czechoslovakia. Here are general parameters to show a backwards US (and western hemisphere in general): PROJCS["Krovak Backward US", GEOGCS["GCS_WGS_1984",    DATUM["D_WGS_1984",       SPHEROID["WGS_1984",6378137.0,298.257223563]],    PRIMEM["Greenwich",0.0], UNIT["Degree",0.0174532925199433]], PROJECTION["Krovak"],PARAMETER["False_Easting",0.0], PARAMETER["False_Northing",0.0], PARAMETER["Pseudo_Standard_Parallel_1",70.0], PARAMETER["Scale_Factor",1.0], PARAMETER["Azimuth",0.0], PARAMETER["Longitude_Of_Center",-110.0], PARAMETER["Latitude_Of_Center",40.0], PARAMETER["X_Scale",1.0], PARAMETER["Y_Scale",1.0], PARAMETER["XY_Plane_Rotation",-90.0], UNIT["Meter",1.0]] The parameters affect the 'look' of the projection in odd ways because the original projection has positive axes west and south, but the XY Plane Rotation parameter is the one that controls the flipping/mirroring of the system. Melita ... View more

Hi Stephen, Based on an earlier thread (on the old forums), I think you need to have a postscript driver for the printer. I checked our standard HP LaserJet's--no option, but a HP plotter had a "mirror image" option on the advanced tab of the plotter set-up. I did find a way (thanks to a colleague) to build a reversed image using a map projection (Krovak), but I don't think it will reverse any symbols or text that you have. Melita ... View more

Change the order of the input x and y values. In Esri-land, x = easting, y = northing and the order is x,y. If coordinates are in a geographic coordinate reference system, they're usually given in longitude,latitude order. Melita ... View more

We probably haven't met in person, and I'm remembering your name from ESRI-L or the web forums. Or I saw your book. Who knows? Or maybe I've confused you with someone else! I handle map projections/datum transformations so if you ever had a question about them, I may have answered it. Melita ... View more

Hi Julii, I remember you! Robert has some great suggestions. If you manage to make to a UC, you'll be amazed at how big it is! I don't know if it will be useful, but could look at some of the older help and articles about migrating from workstation to ArcGIS. They should help highlight the changes in the data formats and user interfaces. I just did a search using "ArcInfo workstation" migration and turned up some items. Possibly also Esri white papers. Here's a page on the geodatabase with a set of links to papers and podcasts/presentations. Melita ... View more

Hi, I haven't used these extensions. Are you using PLTS or ArcGIS for Maritime: Charting? If the latter, check out this help topic: Applying unit conversion and rounding rules (Maritime Charting) There's a note on the page that these need to be set up before importing S-57 data. I found something similar for PLTS when I did a web search. Melita ... View more

Hi Alan, ArcMap has the ability to convert (project!) in-memory between different coordinate systems. To do so, it needs to know both the source and target coordinate systems. The layers or data are the sources. The target is the data frame's coordinate system. You need to leave the layer coordinate system definitions alone. They identify the current reference frame that the data is georeferenced to. If you want to create a copy of the data referenced to a different coordinate system, use the Project Tool. The warning you're getting is specifically about having different geographic coordinate systems (also know as datums). Even if the data frame or a layer is georeferenced to a projected coordinate system, the projected coordinate system is based upon a geographic coordinate system. One way to look at it--a geographic coordinate system identify the size and shape of the model of the Earth and where the latitude and longitude lines area. A projected coordinate system converts from this 3D system into a flat plane. The same location on the ground will have different latitude-longitude values depending on which geographic coordinate system is used. The warning is that there are different geographic coordinate systems in use, and you may need to set some geographic (datum) transformations to reconcile them. The reason that we don't automatically apply geographic transformations is that there are often multiple ones per pair of geographic coordsys or a more accurate transformation may be to use two transformations that convert through a 3rd GCS! Starting at 10.1, we now present a sorted list of transformations in the data frame properties, coordinate system tab, transformation dialog. Melita ... View more