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6

The point at (0°, 0°) is not generally given a name All geographers, cartographers and surveyors ought to know the following, but I reference some sources anyway: According to Matt Rosenberg The point at which the equator (0° latitude) and the prime meridian (0° longitude) intersect has no real significance but it is in the Gulf of Guinea in the ...


6

With 10.2 and above, you can use the Add Geometry Attributes tool to add a field with the length of the features. The tool lets you specify the coordinate system you want to use, in case it is different from the dataset's system. With 10.0, you should work in ArcMap: set the coordinate system of the data frame to WGS 1984 UTM 32N add a field to your ...


5

The Albers equal area conic is the typical projection for historical USGS maps of the lower 48, it being a general-purpose low-distortion compromise for mid-latitude short and wide extents. As a reference on map projections, I like the ESRI book Understanding Map Projections. Its first 30 pages are not unlike a short textbook, followed by ~70 pages of ...


5

It's "there where all the data shows up when something goes wrong". At least that's how I call it, or how I often detect when something went wrong. Others would call it Null Island, which is often used in a humorous way. For an occasional good laugh I would recommend some of the Null Island accounts on Twitter, such as Null Island Gang, Maptime Null Island, ...


5

As @minus34 said above, you almost certainly have latitude and longitude, rather than eastings and northings, so your projection is likely to be WGS84 (or because you're in Australia, GDA94). To do the transformation in pyproj (assuming GDA 94) you can use: import pyproj latitude, longitude = -33.75, 150.0 gda94 = pyproj.Proj(init='epsg:4283') mgaz56 = ...


4

Yes, you still reference coordinates (0, 0) as the origin in respect to the coordinate system as a whole. In essence, coordinate systems are grids in themselves. Therefore, terminology between the two are shared. See how ArcGIS refers to the "Grid" location as the origin.


4

I can confirm that it seems to be a bug. Create a csv file with the following content: E N 600000 200000 700000 200000 700000 300000 600000 300000 Import it as delimited text with EPSG:21781, enable snapping and draw a polygon shapefile on the four points. Without OTF, the result of $area/1000000.0 is 10000 m² (which is obviously correct). Turning OTF ...


3

EDIT - Disclaimer: I would like to refer the readers to the discussion with ChrisW below. It might be that getting an area based upon an OTF CRS is not a bug after all; that is, at least, in arcgis it also being used to allow geoprocessing two layers from different CRS. To elaborate on the issue above. As AndreJ as suggested and show - this is probably a ...


3

You can use the Describe function to get information about your spatial references. Then simply use logic to screen out the spatial reference you do not want. import arcpy arcpy.env.workspace = r'C:\path\to\your\fgdb.gdb' fcs = arcpy.ListFeatureClasses() for fc in fcs: sr = arcpy.Describe(fc).spatialReference.name # Note that you can add ...


3

The N or S value of Latitude is whether the location is North or South of the Equator. W or E for Longitude, is W or E of the Prime Meridian. The number that follows the letter is the Degree of Latitude or Longitude, followed by minutes and seconds of Latitude/Longitude displayed as floats. The alpha-numeric values should not be ignored as they are part of ...


3

You should create new custom CRS and assign it to your layer(s). This quick and dirty approach worked for me after reading all the posts arround here. I use QGIS 2.8.1 and metric system, as I live in Central Europe: import Open Layer (in my case, Google Hybrid) import your data (in my case, our Municipality Border) right click on your data layer and ...


3

This page http://www.vermessung-und-ortung-mit-satelliten.de/datumstrans.html leads you to two excel sheets that do the conversion you want: http://www.vermessung-und-ortung-mit-satelliten.de/excel/transformationen/datumstransformation/GK_DHDN_transformiert_nach_UTM_ETRS.xls ...


3

In getParameterInfo, set a dependency between the two parameters. units.parameterDependencies = [inFC.name]


2

If the transform is unknown, you could use one of the commonly used models that would estimate your transform. If the speed is an issue, you should start with the most simple solutions, check the precision of your model based on the RMSE (you seem to have a large number of points, so you can have a good estimate of the RMSE) and then increase the complexity ...


2

ESRI has defined three projections especially for the contiguos United states. These are included in QGIS as well: EPSG:102003 USA_Contiguous_Albers_Equal_Area_Conic +proj=aea +lat_1=29.5 +lat_2=45.5 +lat_0=37.5 +lon_0=-96 +x_0=0 +y_0=0 +datum=NAD83 +units=m +no_defs EPSG:102004 USA_Contiguous_Lambert_Conformal_Conic +proj=lcc +lat_1=33 +lat_2=45 +lat_0=39 ...


2

The coordinates of the second one ares NOT in laea projection, but in degrees. So you have to Rightclick -> Set CRS for Layer to correct the false CRS information to WGS84 or NAD 83 or NAD27. I don't know what you did wrong, but you may have done the same error with the first layer as well, and they might still not align after sanitizing only the second ...


2

public static bool CompareSpatialRefs(ISpatialReference sourceSR, ISpatialReference targetSR) { IClone sClone = sourceSR as IClone; IClone tClone = targetSR as IClone; // first level test compares the coordinate system component if (!sClone.IsEqual(tClone)) return false; ...


2

You can obtain the spatial reference of a feature class using the IGeoDataset Interface: ' Spatial reference of a feature class Dim geoDataset As IGeoDataset Set geoDataset = featureLayer.FeatureClass Set spatialReference = geoDataset.SpatialReference http://forums.esri.com/Thread.asp?c=159&f=1707&t=223709 OR '''<summary>Get the spatial ...


2

You have to transform the vector layer with a right click on it > "Save as..." You will save a new vector layer (for example "points_21781.shp"). Change the CRS in your 21781, CH1903 / LV03. The new vector layer will have the right CRS.


2

There is another option than converting in QGIS, which is to add the CRS property to the GeoJSON before uploading to CartoDB, see the GeoJSON spec. This means you need to convert you GeoJSON to a feature collection, which may be of use anyway, if you wish to upload more than one geometry. So, at the start of your GeoJSON, you put the CRS of EPSG:27700 (the ...


2

You have coordinates in DMS (degree minute second) format, and need to get them into DD (decimal degree) to import easily into ArcMap. While in Excel, make a new column. This would be the formula to just convert from DMS to DD: degrees, plus minutes divided by 60, plus seconds divided by 3600. =MID([DMS], 2, 2)+(MID([DMS], 5, 2)/60)+(MID(A6, 8, 4)/3600) ...


1

One way is to use the Define Projection Tool in ArcToolbox (or the raster's property page in ArcCatalog). I would pick a related projected coordinate system as a start point. Browse to Projected Coordinate Systems, Continental, Africa and choose Africa Albers Equal Area Conic. Right-click and choose Copy and Modify I would change the PCS name. Update the ...


1

I tried your dataset and: Open the Shapefile with QGIS Set CRS of the layer to "SAD 69 / UTM zone 23 S EPSG 29193" Save layer as Shapefile, with projection "WGS 84 EPSG 4326". After this, we're requested for the datum, choose: "+towgs84=-66..87,4.37,-38.52" It works! :)


1

After posting the question I was able to track down a specific article at Geosoft that answers this. Yes, the "Local Datum Transform" is used to convert to WGS84. https://my.geosoft.com/supportcentre?showOverlay=yes&login=ok#kb/kA230000000VFkoCAG See Local Datums


1

The following ESRI Knowledge Base artcile details the steps to turn your data from Excel into a shapefile. Hopefully you will find this is all you need. http://support.esri.com/en/knowledgebase/techarticles/detail/27589 Note: You will have to convert your coordinates to decimal degrees. Following @Erica's comment, and indeed a re-reading of your ...


1

You are encountering the difference between a projected coordinate system and a geographic coordinate system. Google Earth reads all coordinates as if they were in Geographic Coordinate System WGS 1984, a.k.a. WGS84. So latitude/longitude coordinates (45.215, -162.6548) will show up correctly (as long as you use the WGS84 datum). Your UTM data, on the ...


1

You can do this by going into the catalog and checking the properties window of each feature class under XY Coordinate System. The quickest way would be to compare WKID numbers of each layer. You can also use the Describe function to identify the spatial reference and compare them. see this for more info on this.


1

this is how I identified different projections. Keep in mind that depending on different datum you need the right transformation. You would need elif for each transformation. for lyr in lyrlist: if lyr.visible == True: desc = arcpy.Describe(lyr) Ref = desc.spatialreference.name if "ETRS" in Ref: ...


1

If those "strange" coordinates do not fit to Gauss-Krueger coordinate systems, they might be similar to the "preußisches Koordinatensystem". You will find some links to that in my answer to Conversion of coordinates of "Bochum coordinate system" You have to put up a custom CRS on the point "Trockenberg" in Cassini-Soldner projection, which was ...


1

What Mintx has said is correct but to expand and answer your specific question about the base map SRef... It's not possible to change the SRef of a tiled map service, which all of the ESRI base maps are (and I would imagine most base maps are). This is because the tiles have already been created in the specified SRef. The basemap you use sets the spatial ...



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