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6

As stated in the help simply choose your spatial reference by name or factory code. # Using spatial reference name sr = arcpy.SpatialReference("Hawaii Albers Equal Area Conic") # Using factory code sr = arcpy.SpatialReference(32145) You can find the list of spatial reference factory code here: geographic_coordinate_systems.pdf ...


4

there are several categories in the utm section of esri crs projected. go to the projected coordinate systems. then to UTM, Then look at the nad83 BLM (US Feet). That should work in both autodesk and esri. (EPSG) 32165


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Two common cases: If you created the shapefile you will have to use the Define Projection tool to define the projection/coordinate system. If you downloaded the shapefile: Shapefile has spatial reference (nothing technically you have to do here, should load and re-project on the fly in ArcMap) Shapefile is projected, but no set spatial reference (look ...


3

There are some free applications that let you try and play with projections. like: indiemapper.com flexprojector They also indicate to what extend they preserve size, shape or direction. Depending on you application a different priority might be set. For instance if I had to map an areal phenomenon like e.g. certain species habitat zones I'd prefer a ...


3

You can cheat, because the EPSG numbers for UTM zones have a pattern than incorporates the zone number. 269ZZ for UTM north zones, where ZZ is the zone number 327ZZ for UTM south zones, where ZZ is the zone number And, since PostGIS uses the EPSG number for the SRID, you're all set.


2

The problems arise because the CostDistance calculations use the (Euclidean) distance in a map as a surrogate for the true distances experienced on the globe's surface. This surrogate will be distorted in two ways: The relationship between map distance and globe distance will vary according to location on the map. At any given point, the map-globe ...


2

Thanks for the clarification. It appears that you are mixing the ArcGIS JS API's map object with the Google Maps API's heatmap functionality. This is highly unlikely to work. Instead you could look at the ArcGIS Server JS API's heatmap functionality. This isn't officially supported but stands a better chance of working - see ...


2

You definitely need coordinates or to join that data with existing polygons/points. A quick look at your data shows that it is broken down into boroughs or district numbers. My next step would be to join this data in ArcGIs or QGIS (whatever solution you have available to you) to either the boroughs or districts. This will allow you to visualize the ...


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Have you tried making a custom projection? Here is a walkthrough from esri knowledgebase.


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Open a new dataframe, don't add a basemap, just the shapefile, move your mouse around on the screen and look at the coordinates towards the middle are they small numbers that look like latitude and longitude? Open windows explorer and navigate to your shapefile... look for a *.prj file, if you don't have one, then you are working with data that no ...


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Once you get the shapefile/projection problem solved: Kriging is a method of interpolating points to create a continuous surface. I think that you actually want to use graduated colors to modify the symbology of the points, manually setting classification breaks at the values you need.


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I believe that you are probably encountering the same problem that has been discussed in the old Esri Discussion Forums under the aptly named title of "True Curves, True Evil". I have a reproducible (but long) test case of this phenomena in a Python/ArcPy script that I used to convince a client that what we were seeing was explainable and could be worked ...


2

To a high relative accuracy, in this application--where the region to be mapped will not extend more than a few hundred meters and it is not near either pole--you can treat lat-lon as a Cartesian coordinate system that uses two different linear units of measure. Each degree of latitude will be approximately 111300 meters (and a more accurate value, which ...


2

How are you obtaining your lat/longs out of curiosity? Without access to a DGPS you will be hard pressed to get sub metre accuracy anyway. This 2 point Coordinate Transformations (Basic) spreadsheet is quite useful. Try to use control points at the outer extremities of your site as the further from these points you are the less accurate the transformation. ...


2

The shapefile from Natural Earth contains the south pole. The Mercator projection is not able to render that point for mathematical reasons (it would be in inifinity). What you can do: Set Project CRS from Layer (that would be EPSG:4326) switch to edit mode Delete the bottom line of the antarctic save the layer Change Project CRS to EPSG:3857 If you ...


2

The spatial reference class is very adaptable. Building a little on what Eric said, here's something perhaps more immediately helpful for you, creating the SR object from one of your fcs, then getting the factory code...or likewise you could get it from your 'favorites' if you have it saved. In short, do something like this: # this is prelim code, not to ...


2

Do not use Set CRS for Layer if you want to reproject your data. It changes only the CRS definition, but does not recalculate any coordinate. So set it back to what it was before (WGS84 I assume), and use Save As ... under a different name and different CRS.


1

You'll need to define both a horizontal coordinate system (could be projected, like UTM) and a vertical coordinate system (like NAVD88, making sure to be in the same units as your horizontal). A vertical coordinate system expresses elevations relative to a baseline, usually a mathematical representation of the Earth's surface. Your measured elevations ...


1

Looks like you want a Mercator Projection. Try to save-as your shapefile assigning the WGS 84 / Pseudo Mercator (EPSG: 3857) projection or assign this projection to your project (using transformation on the fly). See also: What is the standard Mercator projection?


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solved It: function calculateArcPointsGeo(center, radius, startAzimuth, endAzimuth, segments) { var pointList = [], point, i, d = radius / 1000, // d = distance in km R = 6371, // km, R = earth's radius (mean radius = 6,371km) lat1 = deg2Rad(center.Y), lon1 = deg2Rad(center.X), ...


1

Given your examples above, you must be using "Nearest Neighbour" option to do the resampling in the Project Raster tool. That's why some values "disappear". What else can it do, it takes the nearest value (measured by cell center position) and assigns it to the new cell in the new coord sys. A histogram of the cell values between the old & new can never ...


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How did you do the setting them all in CRS WGS84? Using Set CRS for Layerhas definitely corrupted your data. This changes the CRS, but does not reproject the coordinates to the new CRS. So delete those layers with 6digit coordinates, and add them again. Usually the CRS information is stored in the file, and should not be altered. As mkennedy noted, they can ...


1

There's another page on the GeoScience Australia website at http://www.ga.gov.au/scientific-topics/positioning-navigation/geodesy/geodetic-techniques/calculation-methods#heading-4 which contains a link to an Excel file. If you download this file, then un-hide rows 8-39, you may be able to unpick their formula and apply it in your app.


1

A geodesist could give better advice than me on your choice of coordinate system but UTM Zone 12S (which I think is around Sri Lanka or the Maldives) seems odd. When I draw your study area (small grid) up against Australia and the MGA Zones it looks like you should probably be using WA Albers (for which I do not have the parameters handy) but Australia ...


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The EPSG manages all available CRS definitions, and also offers polygons of the areas of use. You need to register at http://www.epsg.org/DownloadDataset (for free) to download it. I'm not sure if your intended use matches their terms of license. You have to match the area codes of the shapefiles with the code given in the projection definition database. ...


1

If you are going to do calculations I would go to the trouble of reprojecting your data. Since the majority of your data are in EPSG:32632, I would use the Raster->Projections->Warp tool to create a new version of your DEM in EPSG:32632. The tool is built on the GDAL tool of the same name whose documentation is here. Don't let the documentation put you ...


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Short answer The containerPoint methods date from a feature request back in 2012, and today, they're a bit confusing. The best answer is Leaflet maintainer Vladimir Agafonkin's description: "layerPoint is actually a point relative to the map layer (the div which contains tiles and markers), not the outer map container. What you need is ...



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