# Tag Info

Accepted

### Meaning of "Elevation above surface of ellipsoid"?

The elevation above the ellipsoid (ellipsoidal height) is the elevation above a mathematical model that approximates the shape of the earth. The current most common one is WGS84. These are the ...
Accepted

### Why is SQL Server 2019's STDistance Very Slightly Different Than The Vincenty Formula? (Same Up To ~0.0001km)

SQL Server's STDistance function does not compute geodesic distances. Its algorithm essentially generates straight lines in 3D, densifies them and maps them on the ellipsoid in a manner described more ...
Accepted

### Difference in destination location between pyproj and geopy

It looks like you've done everything correctly. You can evaluate the errors from each method by performing the inverse calculations to find the distance given the origin and destination coordinates, ...

### Difference between Vincenty and great-circle distance calculations?

My apologies for posting a second answer here, but I taking the opportunity to respond to the request by @craig-hicks to provide accuracy and timing comparisons for various algorithms for computing ...

### Meaning of "Elevation above surface of ellipsoid"?

An ellispoid is a mathematical model of the earth that approximates its three dimensional shape. See this definition. Elevation on top of the ellipsoid is 0, but since it's just an approximation one ...
Accepted

### How to measure distance between 2 GPS points in Pandas?

You can do it like this: Cross join the two dataframes using pd.merge. (The key field is just an auxiliary to be able to compute a full cross join.) df_all = pd.merge(df.assign(key=0), df_loc.assign(...
Accepted

### Translating X, Y coordinates to lat/long

Based on your comments there are two steps here: Translating your known coordinates in latitude and longitude to the projected coordinates of EPSG:32723. Calculating the distance to a given cell. To ...

### Why is SQL Server 2019's STDistance Very Slightly Different Than The Vincenty Formula? (Same Up To ~0.0001km)

Without having access to the source code of SQL Server it may be impossible to say. As a comparison, PostGIS ST_Distance query from the geography example of https://postgis.net/docs/ST_Distance.html ...

### Difference in destination location between pyproj and geopy

The geopy pull request fixes your issue with geopy. You will need to install the python package geographiclib first with pip install geographiclib
Accepted

### Haversine accuracy worse when using geocentric radius vs average Earth radius

Ok I figured it out after some research. Instead of using the Geocentric radius I instead calculate the radius Use the “Radius of Curvature formula at azimuth α” formula from the paper (page 5): http:/...

### Meaning of "Elevation above surface of ellipsoid"?

HAE, or Height Above Ellipsoid, or "elevation above surface of ellipsoid", is commonly the form of altitude a GPS receiver returns. It differs from AGL (height above ground level) and MSL (...

### Meaning of "Elevation above surface of ellipsoid"?

An "ellipsoid" is a mathematical approximation of the shape of the Earth. Many different ellipsoids exist, but the two most widely used today are the GRS80 and the WGS84, which attempt to provide a ...

### Difference between Vincenty and great-circle distance calculations?

Whether using vincenty or haversine or the spherical law of cosines, there is wisdom in becoming aware of any potential issues with the code you are planning to use, things to watch out for and ...

### Difference between Vincenty and great-circle distance calculations?

It appears that the geopy.distance package offers a function "distance()" which defaults to vincenty(). I would recommend using distance() on principle, as it is the package recommendation, in case ...
1 vote

### Vincenty or (Project + Euclidean) for accurate distances

GeographicLib has the highest accuracy for measuring distances on ellipsoids of revolution, with a published accuracy of less than 15 nm. For example, using GeodSolve to solve the inverse geodesic ...
1 vote