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8

Be careful as WGS84 is a bit ambiguous. Most of the time it mean EPSG: 4326 that is indeed in degrees (and the base of GPS position) but the name WGS84 could be used for other CRS with different unit (see image exemple below, taken from the website referenced in JGH answer). it's safer to use the EPSG code or to be sure to have the full CRS name to ...


7

Following on Ian Turton's comment... Prior to performing ANY geometry calculations or analysis on a layer(s), the layer(s) MUST be 1) projected to the desired CRS, and 2) that CRS must be the same for all layers. (Sidenote #1: in QGIS, projecting a layer to a different CRS is typically accomplished using Save As...) Your analysis will always fail if the ...


6

Reproject your data: load your text file with EPSG:4326 as CRS Right click on that layer and choose "Export --> Save features as..." Choose the CRS you want your data to be in (WGS 84 58S) Save it (choose a file format you like) Add this new file to your project


5

It is in degrees. You can always check this repository for projection details


5

The JRC Monthly Water History dataset is an image that uses a single coordinate reference system (CRS) of EPSG:4326, and does not use the same CRS as Landsat images (which use a collection of UTM zone spatial references). The 30m resolution refers to the nominal resolution at the projection origin (the equator in the case of EPSG:4326). You can use Earth ...


5

As you say that you accidentally digitized features in a layer in WGS84, my presumption is that you digitized them in Cartesian planimetric coordinates instead of geographic coordinates. For example, I could digitize a square of vertices (-500, -500) and (500, 500). In a planimetric projection reference system, that polygon could be a square of 1000 ...


4

You have to import CSV file as EPSG:4326 (seems like it from the extent). QGIS will do on the fly reprojection into 3857. Don't forget to put Lat as Y and Lon as X. Right now you are saying that your layer is in the 3857 projection. Which I guess is not true, right? Web mercator EPSG 3857 has coordinates from -20048966.10 to 20048966.10 and you have LatLon ...


3

On the page you gave reference to we can the following definition of EPSG:3844 in WKT PROJCS["Pulkovo 1942(58) / Stereo70", GEOGCS["Pulkovo 1942(58)", DATUM["Pulkovo_1942_58", SPHEROID["Krassowsky 1940",6378245,298.3, AUTHORITY["EPSG","7024"]], TOWGS84[33.4,-146.6,-76.3,-0.359,-0.053,0.844,-0.84], ...


2

ArcGIS should not expect a SRID string that you are trying to attach. The OGC implementation guide http://www.geopackage.org/guidance/implementation_guide.html has a link to sample GeoPackage that implements the lowest level SRS support the three built-in SRSs of EPSG::4326 (WGS-84), 0 (undefined geographic coordinate reference systems), and -1 (undefined ...


2

tc stands for True Course. The term True Course is used in navigation to express the bearing in which the ship is traveling. It is used to differentiate that measured from the geographic north with respect to those measured from the magnetic north. In your formula, it represents the bearing of the distance (arc lenght) d at the starting point (the ...


2

I think there is a problem with the way you are thinking about the whole thing. To sum up: You use Cesium points which are from a Digital Elevation Model. Those points are expressed in WGS84 and the height representation is ellipsoidal height GPS gives you height which is ellipsoidal height You have geoid height from the EGM2008 model So when you ...


2

First, I will assume that your points are in WGS84 = EPSG: 4326. Convert the lon/lat points to UTM meters using pyproj. First we need to get the correct projection. The issue is that to convert to UTM you need to know your UTM zone. That is something you can look up separately; UTM zone will depend on the longitude of the initial shape. import pyproj proj ...


2

Use a Polyline for something like this. Here's a live demo. var viewer = new Cesium.Viewer('cesiumContainer'); var airportData = { "EDDM": { "icao": "EDDM", "iata": "MUC", "name": "Munich International Airport", "city": "Munich", "state": "Bavaria", "country": "DE", "elevation": 1487, "...


2

The fundamental problem is that the UTM zone is so far off the correct one that the projections don't behave as expected. The utm zone should be 31. It is odd that the central meridian is correct even in this case, but it is. Using the correct zone gives prompt> echo 3 0 | proj +proj=utm +zone=31 +ellips=wgs84 500000.00 0.00 prompt> echo 3 -.0001 |...


2

They are certainly not the same. WGS is a datum(for lat/loong specifations) while EPSG is a database of CRS and related information. Those who think these are same actually ignore the basic purpose of EPSG. The main purpose of EPSG is to assign a code for Geodetic Parameter Dataset that contains a repository of parameters needed to define a CRS. This ensures ...


1

I think the data's in the Philippines. Is that correct? The latitude, longitude values are in DDMM.mmmmm, packed degree-decimal minute values. For example, 3020.13221706(latitude),N, = 30° 20.13221706 = 30.00220361767 12118.46433560(longitude),E = 121° 18.46433560 = 121.3077389267 This is confirmed by several sites like this one. What you will need to ...


1

So effecively you are interpolating coordinates linearly across the tiles. Unless I'm overlooking something, that might give you some wonky shape distortions at smaller scales (more zoomed out), but it should not give the kind of effects that you are seeing. If you are using the same tile numering scheme as OSM, you could try comparing one of your tiles from ...


1

If M value is a measure value, there's no information about what unit it might be using when the xy coordinate system is geographic. The spatial reference doesn't have a unit for the measures. If the xy coordinate system is projected, you can guess that the measures are using the same unit, but that may not always be the case. As an example, the measures ...


1

Just so the answer is in here and not in the comments, I'm adding based on @TomazicM answer above Going to epsg.io (epsg.io) and searching for Lo29 gives you two most likely candidates: EPSG 2053 and EPSG 22289. First coordinate in your table is X and second Y. You have to add constant 2,700.000 to Y. See https://epsg.io/map#srs=2053&x=72058.999544&...


1

If you have an accuracy near centimeter-level and you are wondering if you need to convert from WGS84 to GRS80 ellipsoid height, there is no reason to The difference between both ellipsoids is at a sub-millimeter level (US and European made a different rounding on the ellipsoid flattening) WGS84 doesn't have any geoid definition. The use of ellipsoid or ...


1

Problem solved: It worked fine with cubic convolution and bilinear interpolation with ArcMap 10.6. Thx for the tip!


1

Modifying the code from here to get a complete runnable example: https://stackoverflow.com/questions/24950614/abnormal-output-when-using-proj4-to-transform-latlong-to-utm Your output is in Radians, so converting to degrees and printing to higher precision should show the difference: [excerpt] double x = 6000.0; double y = 122.0; [excerpt] int ...


1

You need to use Query.setCoordinateSystemReproject(CRS) not Query.setCoordinateSystem(CRS). One changes the output coordinates and the other tells the system what CRS the coordinates of any geometries in the query are in. This code fetches the boundary of Pennsylvania in EPSG:2272. public static void main(String[] args) throws IOException, ...


1

You have several options. Keep in mind that once you convert to a Cartesian coordinate system, the farther you go from the point of origin (0,0,0 in Cartesian space), the less accurate your coordinate system will be. On option is to use the Universal Transverse Mercator (UTM) projection. Wikipedia will give you a lot more information (and math), but there ...


1

Use Project Tool. http://desktop.arcgis.com/en/arcmap/10.3/tools/coverage-toolbox/project.htm Define projection is for feature classes without any CRS defined. Also check: C:\Program Files (x86)\ArcGIS\Desktop10.X\Documentation for geographic_transformations.pdf which will help you to pick correct transformation.


1

There are two atomic procedures here. Convert the projected coordinates from the State Plane zone (in US survey feet) to latitude-longitude on NAD83. (specifically, Lambert conformal conic) Convert the NAD83-based latitude-longitude values to WGS84 latitude-longitude values. As commenters have said, try using existing software like GDAL, PROJ.4. National ...


1

Seems to be a problem with the CRS of the shapefile layer. In QGIS, it can be changed in Layer > Properties > CRS. Changing the CRS of the layer doesn't modify the coordinates of its geometries, but the way they should be interpreted. When you find and assign the correct CRS in which the coordinates of the geometries must be interpreted (always ...


1

You can download the differences between the WGS 84 spheriod and the Earth Gravitation Model 2008 (EGM2008) in an ESRI grid format here: http://earth-info.nga.mil/GandG/wgs84/gravitymod/egm2008/egm08_gis.html The value in each cell is the amount you need to add or subtract from the WGS 84 elevation to get the geoid (sea level) elevation. Disclaimer: I'...


1

You did not tell the CRS of the image, but the lack of information itself tells that you missed the first step to deal with a non-georeferenced image. The tool you used on the image Set Coordinate Reference System does set the CRS information by over-riding existing metadata. However, it does nothing if there is no metadata to be modified. Follow these ...


1

Look very carefully at the signs when writing a towgs84 statement, in this case a minus sign was wrongly inserted, towgs84=-117.763 should be towgs84=117.763


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