Latest Contributions by MelitaKennedy

Hi, I have a file geodatabase that I created in v10 but I need to provide it to someone who is running 9.3.1. Is there a way to convert my database from v10 to v9.3.1? You can't convert it directly, but you can create a 9.3 geodatabase using the Create File GDB tool in the Workspace toolset of the Data Management toolbox. http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//0017000000pw000000.htm "Jay" on http://gis.stackexchange.com mentioned that James Fee has posted a set of empty geodatabases from the various ArcGIS versions on his blog. You can find them here: http://www.spatiallyadjusted.com/2006/11/21/esri-92-personal-geodatabases-in-arcgis-91/ Melita ... View more

Thanks, Melita.  That info looks promising. A couple of questions: 1) In your example, you say that only NAD_1927_To_NAD_1983_NADCON is loaded by default, then the code adds NAD_1927_TO_NAD_1983_AK to the collection.  Does this replace the original NAD_1927_To_NAD_1983 transformation, or add a second one?  If it adds a second one, how does ArcMap determine which one to use when converting from NAD27 to NAD83?  Does it prompt the user? 2) Will changes to the geographic transformation list is be saved with the map document? Cheers, Bob Hi Bob, I'm sorry that I wasn't clearer. 1) Only one transformation per pair of GCS is allowed, so the Alaska transformation will replace the "NADCON" (actually for contiguous US, the lower 48). 2) Yes, the GeographicTransformationOperationSet is saved in the map document. Melita ... View more

Thanks, Venkat. Is there an event that fires before ArcMap starts the automatic transformation? Is this automatic transformation done using a geoprocessor?  If so, how do I get access to the geoprocessor so I can handle its ToolExecuting event?  I'm looking for something that will allow me to hook into ArcMap in order to possibly update the IGeoTransformation before the input features get transformed to the data frame's coordinate system. Thanks, Bob I don't know if there's an event, but part of what you're looking for is IMapGeographicTransformations. See VBA (sorry!) below on how to change the default transformation loaded upon opening a new map document. Only NAD_1927_To_NAD_1983_NADCON is loaded by default. Private Function MXDocument_NewDocument() as Boolean    ' Start by getting a handle on the current FocusMap    Dim pMxDoc As IMxDocument    Set pMxDoc = Application.Document    Dim pMap As IMap    Set pMap = pMxDoc.FocusMap    Dim pSpRFc As SpatialReferenceEnvironment    Set pSpRFc = New SpatialReferenceEnvironment    Dim pAlaskaNADCON As IGeoTransformation    set pAlaskaNADCON = pSpRFc.CreateGeoTRansformation(esriSRGeoTransformation_NAD_1927_TO_NAD_1983_AK)    '  Add the transformation to the operation set    Dim pGTSet As IGeoTransformationOperationSet    Set pGTSet = New GeoTransformationOperationSet '  The Map uses IMapGeographicTransformations to access the geogtrans    Dim pMapGeo As IMapGeographicTransformations    Set pMapGeo = pMap    Set pGTSet = pMapGeo.GeographicTransformations    pGTSet.Set esriTransformForward, pAlaskaNADCON    pGTSet.Set esriTransformReverse, pAlaskaNADCON End Function Melita ... View more

Sorry about the attachment I must have made it too small. The original XY plots were in meters and I used the calculate geometry tool to change this to DD. This worked just fine, but with some negative values. These values were commonly negative to -2 or -3 DD, these points fall outside of the UTM grid I was told to put the points into (37N) so are an eventuality I figure. Thank you very much for your help. Oh, I see. I bet the negative DD values were in the latitude/Y field. Thanks! ... View more

I am and have successfully added X,Y data using the built in ArcGIS toolbox 'data management tools' > 'Features' to add X, Y data to the attribute table from point data. However this has caused a problem, for I have been using the data to build up a model in Petrel, hence exporting the X,Y coordinates via a text file and my collegue dosen't understand why the coordinates have negative values. I suggested this is due to them being south of the 'equator' and west of the central meridian on the projection system I have been using. Is there a way of exporting the X, Y values in Decimal Degrees rather than meters (which I think it exports the data as)? I have a screen shot below showing the negative attributes in the Y coloumn. The values are quite large intergers suggesting meters as the output type. Hi Simon, If the data does have a defined coordinate system, you can use the calculate geometry option on the attribute table in ArcMap. First set the data frame's coordinate system to what you want the values to be. The calculate geometry tool will then let you choose to use the data frame's (or the data's coordinate system. For some reason, I could only access a thumbnail of your attachment so couldn't see what the coordinate values were. Data that's in a geographic coordinate system will have negative X/easting values if the data is west of the prime meridian (usually Greenwich) or negative Y/northing values if south of the equator, and values will be relatively small. Data in a projected coordinate system (PCS) would normally have negative values to the west and south of the longitude/latitude of origin. That could be the central meridian, or have other names. However, most PCS have false easting or false northing values applied to make sure most of the data has postive coordinate values. In fact, seeing negative numbers with data in a PCS can be a sign that the data is outside the normal usage. Melita ... View more

Melita,     Thank you for your response. Yes, you are correct that the original GEOTIFF is georeferenced, but comes without a spatial reference. Based on the Burned Area Manual, I know that it has been reprojected from Sinusoidal into Platte Carree and I have no issue defining the GEOTIFF as such. But, I need a projection that preserves accurate area, thus Albers Equal Area for the CONUS is ideal. this is what I've tried: 1) in ArcCatalog or in ArcMap (I've tried both) I go to the properties of the file and give it the Platte Carre projection (WGS 1984 by default) I've also now tried assigning it your MODIS sphere proj. 2) Next, I go to arctools > data management > projections and transformations > project raster. For the input I select my file, it shows up with the projection I just defined. For the Output I select projected coord system > continental > North America > USA contiguous Albers Equal Area Conic.prj. Then the only thing I modify is the latitude of origin, changing it to 0.here it is: Projection: Albers False_Easting: 0.000000 False_Northing: 0.000000 Central_Meridian: -96.000000 Standard_Parallel_1: 29.500000 Standard_Parallel_2: 45.500000 Latitude_Of_Origin: 0.000000 Linear Unit: Meter (1.000000) Geographic Coordinate System: GCS_North_American_1983 Angular Unit: Degree (0.017453292519943299) Prime Meridian: Greenwich (0.000000000000000000) Datum: D_North_American_1983   Spheroid: GRS_1980     Semimajor Axis: 6378137.000000000000000000     Semiminor Axis: 6356752.314140356100000000     Inverse Flattening: 298.257222101000020000 3) as soon as I click ok, the program shuts down, every time. It seems the issue is related to the difference in spheroids between WGS 1984 or MODIS sphere and the NAD_1983 sphere. And I know there are some transformations for them, but I can't get them to work. The other part of my problem is that I'm trying to get this burned area to overlay with a cropland data layer I have for the conUS. here is the projection specs for my cropland data layer. This is not the original projection, it was reprojected to this via ArcInfo workstation, which as I understand assigns the clarke 1866 as a default. I was given this layer this way and have to make the two overlay accurately to determine how much burned area is cropland. Projection: Albers False_Easting: 0.000000 False_Northing: 0.000000 Central_Meridian: -96.000000 Standard_Parallel_1: 29.500000 Standard_Parallel_2: 49.500000 Latitude_Of_Origin: 0.000000 Linear Unit: Meter (1.000000) Geographic Coordinate System: GCS_Clarke_1866 Angular Unit: Degree (0.017453292519943299) Prime Meridian: Greenwich (0.000000000000000000) Datum: D_Clarke_1866   Spheroid: Clarke_1866     Semimajor Axis: 6378206.400000000400000000     Semiminor Axis: 6356583.799998980900000000     Inverse Flattening: 294.978698200000000000 So, I've also been trying to get the Burned Area geotiffs into a Clarke_1866 albers, but I have no experience with ArcInfo Workstation and haven't been able to reproduce what my boss did with the cropland data layer. This must seem like such a mess, at least it does to me, hopefully not to you! The bottom line is that I need to get those GEOTIFF's into an alber's projection that will overlay with the cropland data. Is this possible? Can you think of any way to do so? Again, thank you, Melita. Carie Hi Carie, Oh yes, transformations. First, can you overlay the Burned Area data with your cropland data in ArcMap? Ignore any warning messages about different geographic coordinate systems/datums. If it doesn't overlay, try defining a custom transformation. Data frame properties, coordinate systems tab, Transformations, New button. In the New dialog, change the method to Geocentric Translation, leave the parameters set to zeroes. OK all and recheck the overlay. Melita ... View more

Hi, I have recently been compiling maps of Iraq on a UTM grid scale, so have been using the UTM grid projection system. However, what projection system and datum should one use when creating maps for the entire country? EPSG (http://www.epsg-registry.org) lists an ED 1950-based Iraq National Grid. We added it at version 10. It uses transverse Mercator. There's a newer IGRS geographic coordinate system, and 3 UTM zones based upon it, but no national grid. IGRS is close to WGS84, according to EPSG. Melita ... View more

Hello, I can't seem to get anywhere on this and am hoping that Melita might be able to respond since it seems she has been dealing with this a lot, but any help is appreciated. I have GEOTIFF's provided by the University of Maryland for MODIS burned area for years 2003-2009. I am trying to take it from a Platte Carree projection to Albers Equal Area. please help me! thanks to all, Carie Hi Carie, What problem are you encountering? Does the original, downloaded GeoTIFF have a defined coordinate system? Does the data appear to be georeferenced (the raster extents aren't equal to 'cell' counts)? If georeferenced but doesn't have a defined coordinate system, what happens when you define its coordinate system? The online documentation is less than helpful about the coordinate system details, isn't it? I'm assuming that the GCS/Datum is the same as listed in the report. Because I can't attached .prj files, here's the contents of the a .prj file: GEOGCS["GCS_MODIS_Burned_Area_Sphere",DATUM["D_MODIS_Burned_Area_Sphere",SPHEROID["MODIS_Burned_Area_Sphere",6371007.181,0.0]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]] Place it in a text file (no word wrapping, single line) with a .prj extension and place it in coordinate systems, geographic coordinate systems. Now you can create a custom projected coordinate system with this as its geographic coordinate system. Just leave the Plate Carree parameters as-is. I assume the central meridian is zero. Melita ... View more

Again - thanks for your reply - I have the standard toolbar active and the scale is not on there as defaulted by the add data button. Apparently some predecessor of mine turned it off or something. 😞 I have looked in the customized options to add that 'button' (which I have not found) as well as going through the options on the data frame properties. This should be fairly simple can anyone please help - Thanks!!!! Hi, I'm not sure this will work, but click the arrow at the right of the standard toolbar and select "Customize". If you hover over it, you should see "Toolbar options". This will open the customize dialog. Select the Toolbars tab and highlight the Standard toolbar. Click the Reset button at right. This will get rid of any custom buttons on the toolbar--it removed my project wizard button, for instance. Hopefully, it will replace the missing control! I also saw a "Map Scale" control on the Commands tab, Pan/Zoom set, but wasn't able to drop it onto a toolbar, so I don't know if it's the same control or not. Melita ... View more

Argh.... Its things like this that make me despise working with ArcSDE and ESRI products.  How is there two different WGS 84s?  SRID 4326 (and Oracle's coordsys) are geospatial standard WGS 84 definitions. EPSG:4326 .prj definition: GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137,298.257223563]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]] ArcGIS WGS 84 .prj definition: GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137,298.257223563]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]] These are identical definitions.  How does ArcSDE get confused?  How does Oracle Spatial screw up 4326? Here's Oracle's 4326 from 11g: GEOGCS [ "WGS 84", DATUM ["World Geodetic System 1984 (EPSG ID 6326)", SPHEROID ["WGS 84 (EPSG ID 7030)", 6378137, 298.257223563]], PRIMEM [ "Greenwich", 0.000000 ], UNIT ["Decimal Degree", 0.01745329251994328]] Here's ours from ArcGIS 10: GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984", 6378137.0, 298.257223563]],PRIMEM["Greenwich", 0.0],UNIT["Degree", 0.0174532925199433],AUTHORITY["EPSG",4326]] We've started including an AUTHORITY tag for the top level object. This would be one of the easier entries to try to "make equal", but it's complicated in code to do it reliably without just taking the SRIDs at face value. The values are all 'equal', but does that really mean that the WKT versions (if you didn't have the SRIDs) represent the same coordinate reference system? Melita ... View more

Hi there, I want to reproject a few raster datasets from GCS_WGS_1984 to NAD_1983.  The data is for the province of British Columbia in Canada.  Could someone help me choose the correct transformation?  My options range for NAD_1983_To_WGS_1984_(1 through 8).  There is no mention of British Columbia in this ESRI document (http://resources.arcgis.com/content/kbase?fa=articleShow&d=24159) describing each of these transformations. Thanks, Rob Hi Rob, What's the cell size on the rasters? If they're more than 1m, don't worry about it. If they're significantly less, try using NAD_1983_To_WGS_1984_5. Melita ... View more

Hi Melita, Thank you for your reply. The projection information is correct (NAD83 Albers USGS version). I created a new raster in UTM 18N using the Project Raster tool. Now the data aren't aligning (screen shot attached) with another feature with the same projection information (UTM 18N). The planar distance units for the raster and feature are both meters. I've had this problem in the past, but I can't remember what the issue was. [ATTACH]3120[/ATTACH] Why aren't the data lining up? Please let me know if you need more info. Again, thank you. Regards, Mike Hi Mike, Does the original raster line up? If it doesn't, then we have an issue with the original raster. If it does, then we can focus on what happened when the raster was projected. How far off is it? Are you certain that the other data is in the correct location? Melita ... View more

Hi there...                I am a student jus started on my college project.. I am thinking of finding the best projection suited for various regions of the  world taking certain factors into consideration....  well I am not clear enough like what image format should I prefer to use in my scenario here?!! where can I possibly get the  free data to implement this... i am jus confused like where/ how to start this... So any ideas or suggestions are truly welcome... Thank you... Hi, I can't help you on where to find a free world raster. See if you can get access to the Esri Data & Maps CDs/DVDs. Or check USGS website. For your project, see if you can find a copy of Canters, Frank. Small Scale Projection Design. Also useful might be: Snyder, John P. Flattening the Earth. which discusses the different projections created over the centuries and what they were used for. Melita ... View more

Hi, I attempted to find a thread that already exists for this problem, but I could not find one. I would really appreciate some guidance with this. I am having trouble projecting a raster grid. When I try to load the file, I get a message saying "error, inconsistent extent.." Also, when I try to transform the projection it fails with a general 999999 message, with no useful information. I defined the projection as: North American Datum of 1983. Then attempted to transform the projection to: NAD_1983_UTM_Zone_18N. The process fails and I get the inconsistent extent message. Extent information from the layer property source table is as follows: Top: 2584425 Left: 1605495 Right: 1932525 Bottom: 2123805 Here is the spatial ref information from the metadata: Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Map_Projection: Map_Projection_Name: Albers Conical Equal Area Albers_Conical_Equal_Area: Standard_Parallel: 29.500000 Standard_Parallel: 45.500000 Longitude_of_Central_Meridian: -96.000000 Latitude_of_Projection_Origin: 23.000000 False_Easting: 0.000000 False_Northing: 0.000000 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: row and column Coordinate_Representation: Abscissa_Resolution: 30.000000 Ordinate_Resolution: 30.000000 Planar_Distance_Units: meters Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1983 Ellipsoid_Name: Geodetic Reference System 80 Semi-major_Axis: 6378137.000000 Denominator_of_Flattening_Ratio: 298.257222 What is going wrong here? Hi, The metadata description looks like NAD83 Albers USGS version (in projected coordinate systems, continental, north america) except the latitude of origin parameter is missing. Based on the raster's extent, I think it is the USGS Albers because the extents place the raster around northern NJ, eastern NY up to southern VT. If the raster does not represent that part of the world, the Albers coordinate system information could be incorrect. I'm confused by your statement that you defined the coordinate system as NAD83--the geographic coordinate system? You need to leave it as Albers (hopefully, it's correct) and then use the Project Raster to create a new raster in UTM 18N. The 'inconsistent extent' is classic if a dataset is georeferenced to a projected coordinate system, but is assigned a geographic coordinate system. "Projecting" data via the Define Projection tool or the data's property page in ArcCatalog updates the metadata only. The data values are still relative to the previous coordinate system. Melita ... View more

I have similar problem when I tried to migrate my 9.3 C# code to 10.0. I got error message for ISpatialReferenceFactory spatialReferenceFactory2 = new SpatialReferenceEnvironmentClass(); the error message is "Retrieving the COM class factory for component with CLSID {7B5B7020-C4F6-11D1-BC92-0000F875BCCE} failed due to the following error: 80040111." Then I tried to use activator so I revised the code to following: // Set up the SpatialReferenceEnvironment.             // SpatialReferenceEnvironment is a singleton object and needs to use the Activator class.             Type factoryType = Type.GetTypeFromProgID("esriGeometry.SpatialReferenceEnvironment");             System.Object object1 = Activator.CreateInstance(factoryType);             ISpatialReferenceFactory2 spatialReferenceFactory2 = object1 as ISpatialReferenceFactory2; However, I still got the same error message. Can anyone help on this one? Thanks a lot. Wei Hi Wei, Another post with a similar issue said that he needed to add this: ESRI.ArcGIS.RuntimeManager.Bind(ESRI.ArcGIS.ProductCode.Engine); (or other licensing information). Melita ... View more