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23

This is an intrinsic feature of ArcGIS. Just open "Geographic Coordinate Systems" folder, then the "Solar System" folder, then choose "Mars" and the datum associated with your data.


5

The column format for PostGIS is called geometry and you'll probably need to read up on all the functions associated with managing spatial columns. If you are getting the lat/longs from GPS or Google, the projection will be EPSG:4326. edit: iant's comment brings up a good point about the geography type, and indeed if you are using EPSG:4326 it looks like ...


5

If the substation coordinates are given in latitude and longitude, the CRS can not be EPSG:32629. EPSG:4326 seems more reasonable, or a local datum with degrees as units. You should not use Set Layer CRS to cahnge the CRS, but save As ... to a different name and CRS. You can install openstreetmap background with the OpenLayers plugin to see if the stations ...


4

Jason shared the dataset via email, and it seems that the problem is due to a datum mismatch. Because the original dataset uses the GDA94 datum, and the Leaflet map uses WGS84, a datum transformation is necessary. This is covered in the QGIS manual at Working With Projections.


4

Looks like a pure projections issue, not a Leaflet issue. My tool of choice for CRS transforms is ogr2ogr, which can take your EPSG:3111 shapefile and output a GeoJSON: $ ogr2ogr -s_srs EPSG:3111 -t_srs EPSG:4326 -f "GeoJSON" projected.json original.shp In my experience, ogr2ogr is a very flexible and powerful tool for CRS and format transforms if one ...


3

The best thing would be if you can speak with the person who created the layers and try to discern if they might have accidentally put something/defined something in the incorrect projection. Or maybe it was poorly digitized. I have had some success guessing if the projection is just a zone or two off and simply redefining the projection. If someone ...


3

"In Oracle, calculating the distance on WGS-84 gets me the result in degrees." That can only happen if your geometries are defined without any explicit SRID (= SDO_SRID is set to NULL). In that case, the database has no clue about what you are actually storing: it does not know that your data is actually geodetic. All it sees is some numbers that it assumes ...


3

It looks to me like the Lambert projection file has an error. GRS_1980 is a spheroid, not a datum. The NAD83 datum is based on the GRS_1980 spheroid. I think it is possible that your Lambert projection is actually using the NAD83 datum. Your datum transformation throws an error because you are not trying to transform between WGS_1984 and NAD83. If it were ...


3

Example for reprojection from EPSG:2193 to EPSG:3857 c:\OSGeo4W64\bin\ogr2ogr.exe ^ -f "MSSQLSpatial"^ "MSSQL:server=DestServerName;database=DestDbName;trusted_connection=yes"^ "MSSQL:server=SourceServerName;database=SourceDbName;trusted_connection=yes"^ -sql "SELECT [Id], [Shape].STAsText() Shape FROM [SourceDbName].[dbo].[SourceTableName]"^ -nln ...


3

The problem is you are assigning metadata to the object, and probably even overwriting the existing metadata. This happens here: projection(pr) <- mycrs You should first run this to see what raster thinks it is already: projection(pr) or just print the object out to get a fully summary: pr Going out on a limb, I think you should warp this ...


2

I had the same problem and simply convert .xlsx to .csv only helped to display the x coordinate. I used the table to table file to create a new table from the .csv file and define the field type to be numeric. After that it worked. To me it seems to be more of an excel problem rather than an ArcGIS 10.3 problem...


2

There is a straightforward, disciplined way to analyze such data: linear regression. It can work because (a) the range of these points is a relatively small part of the world and (b) to a close approximation over such ranges, projection formulas are nearly linear as a function of latitude and longitude and--with more data--even their departures from ...


2

Yes, it's possible. Convert the known coordinates from lat-long into various coordinate systems and see what matches. Looking at a few of your lat-long values, it seems that your data is in California, so my guess would be California State Plane; this may be in meters or feet, but the conversion will tell you quickly.


2

you can use gdalbuildvrt instead of gdalmerge to create a virtual raster template (xml file) that will behave like a merged raster. then you can run gdal_translate with the -projwin option for your set of 256*256 tiles. For most of my applications, I would create a single output per face then use gdalbuildvrt for virtual tiles. Note that if you create one ...


2

The distortion in MODIS imagery people mostly worry about is the well known Bowtie effect due to whiskbroom scanning. The Sinusoidal projection, or Sanson-Flamsteed, is an equal area projection and thusly both tiles you mentioned cover roughly the same area and have identical pixel sizes.


2

I downloaded your data and had a play around in QGIS - if I choose EPSG:102022 (Africa_Albers_EAC) it looks like it lines up. Depending on your plans for this that might be close enough - obviously for real science(tm) you'll need to go back to NOAA (or the publications listed) and check. Or you could try editing the spheroid definition below. ...


2

Is the raster format an Esri GRID? If so, the original LCC definition may have used NAD83 (CSRS) which isn't supported in the PRJ.ADF file format used by Esri grids. The definition doesn't match any of the existing Canadian LCC definitions, but it's close. Do try to change the geographic coordinate reference system only to NAD 1983 (North American 1983) ...


2

The purpose of the map here will really decide which CRS you will use. You basically have 2 options, a geographic coordinate system or a projected coordinate system and depending on what you want to accomplish will help you choose which system you want to make a map in. ...


2

I think we can over complicate this answer. It is meters, as UTM Zones are almost always going to use meters as their unit (exceptions are so rare as to not be worth a mention). If you suspect you are using something that is not meters it will say so. Use this site as it is software independent if you must look it up. http://spatialreference.org/ Then ...


2

I found the solution (maybe this will help someone), I have to write the Spatial reference into the CRS variable, then netcdf can recognize all projection info which is defined. crso.spatial_ref = str(srs) str(srs) gives me: crs#spatial_ref=PROJCS["Azimuthal_Equidistant", GEOGCS["WGS 84", DATUM["WGS_1984", SPHEROID["WGS ...


2

Yes, it is a meaningful difference, there will be some difference in reprojecting. Those 7 parameters define a datum shift (translation + rotation + scaling). If the postgis reprojection is better than the other one, just add those parameters to the Proj4js definition. You can find additional information on the towgs84 param here ...


2

As @mkennedy says the LayerFile is a "pointer" to the actual data but it can hold stuff like symbology, definition queries and basic metadata. You can set up the IMapGeographicTransformations or how about doing away with the whole problem by projecting your data into OSGB, create a LayerFile for your data (now in OSGB) and load that? I suggest this ...


1

All used shp-Files have the EPSG 31468. I run the model, add a field and calculate the area the sum of all records will be 10275 m² When I do the same with field calculator form the gui the sum of all records will be 10311 m². When I use a other gis I get always this result


1

WGS 84/NSIDC EASE Grid-Global seems to be a stereographic projection, which does not preserve areas. This is the reason why you can't get meaningful results. The most simple solution is to reproject your layer to a UTM projection suited to your area of interest.


1

you can use an equal area projection to get the area corresponding to the surface of the Earth. Using shapely is not a problem if you use the appropriate projection. Just make sure that you densify your shapefile vertics before you project it. Examples of equal area projections include cylindrical equal area and sinusoidal projection.


1

You do not need a projection if your coordinates are arbitrary. If you are going to use a basemap to pick a corner of the building provided by Arcmap then you are stuck with WGS84. Autocad offers free trial and complete student edition if you are a student. There are many open source drafting programs to choose from but your question does not state an OS ...


1

The process that you need to do in order to reproject your image is called georeferencing. For basic/linear georeferencing, the minimum number of points you need is 3 so if you have 4 corners you should be fine. There's a few tutorials available on the net based on Arc and QGIS tools that can show you how to perform this on raster images. I've never used ...


1

Have you tried specifying the units. Based on this https://docs.oracle.com/cd/B19306_01/appdev.102/b14255/sdo_objgeom.htm#i857957 "Unit of measurement: a quoted string with unit= and an SDO_UNIT value from the MDSYS.SDO_DIST_UNITS table (for example, 'unit=KM'). See Section 2.8 for more information about unit of measurement specification." I would think: ...


1

The unit of the projection is used for area calculation, meter or decimal degree or feet. Check Settings/Options/Crs, see screenshot:


1

I think that you should check a few items: check layer CRS check project CRS (set automatically reprojection on the fly in: Settings > Options > CRS) After open vector layer in QGIS use tool "identify Feautures" and select one feauture In "Identify Results" dock window "expand all" and look for area units Now you can use "Filed calcuator" or Vector > ...



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