Take care to use consistent capitalization (you slipped up in @POINT_b). In the application it have two textboxes and one button. Finally, we used the most accurate Vincenty’s formula. 9. The code is working (no errors) but I keep gettting a wrong result. This is the distance in a straight line, if you need the distance on a path you will have to find all points on that path and then calculate the distances between each two points and then take the sum of that. Task. We use the Haversine formula to caulate the relative distance between the static input coordinate, and the coordinates from the data source. Posted - 2007-03-28 : 22:43:31. I’ve discussed the Haversine formula in an article about Distance And Bearing Calculation in Power BI (I’ll link this once it’s published). Law of Haversines. The great circle formula is given as follows: d = rcos-1 [cos a cos b cos(x-y) + sin a sin b]. sometimes getting right and sometimes getting irrelevant distance. I have haversine formula for two points and its works great. Then enter the latitude and longitude of your destination point in cells A2 and B2, also in degrees. If the length of the three sides is (from u to v), b (from u to w), and c (from v to w), and the angle of opposite view c is C, so that the law of haversines consists of three, as follow: haversine(c)=haversine(a−b) sin(a)sin(b)haversine(C) (1) The Haversine formula serves to find the distance between the user's location and the destination Add a comment. So right now, I'm doing a homework assignment for a C++ class. The haversine formula is an equation important in navigation, giving great-circle distances between two points on a sphere from their longitudes and latitudes. c# - Geographic coordinate distance calculation with haversine formula gives the wrong output - Stack Overflow Geographic coordinate distance calculation with. Teams. radians (coordinates)) This comes from this tutorial on clustering spatial data with scikit-learn DBSCAN. 5707963; R = 3956; /* the radius gives you the measurement unit*/ a = HalfPi - latoriginrad; b = HalfPi - latdestrad; u = a * a + b * b; v = - 2 * a * b * cos(longdestrad - longoriginrad); c = sqrt(abs(u + v)); return R * c; The Haversine formula calculates the shortest distance between two points on a sphere using their latitudes and longitudes measured along the surface. /// </summary> public enum DistanceType {. Task. Resolviendo d aplicando el haversine inverso o usando la función seno inversa, obtenemos:Package haversine is a Go library which implements the haversine formula. The haversine formula 1 ‘remains particularly well-conditioned for numerical computation even at small distances’ – unlike calculations based on the spherical law of cosines. The Haversine Formula is more accurate than the law of cosines formula How can I rework Haversine formula to solve for an individual coordinate given the other 3? What I have tried is to use sympy, but the calculation seems to time out, unless I have a symbol wrong somewhere. Recall that in this formula, we are finding the great circle distance. In this post, I am going to show you how to find the nearest location/s based on a specific location. The first is that while the ArcGIS Map has an option for distance radius, it only allows a maximum of 100 miles / 161 kilometers. Add a comment | 47 I found this post very useful so here is the solution in PHP. Vincenty's formulae are two related iterative methods used in geodesy to calculate the distance between two points on the surface of a spheroid, developed by Thaddeus Vincenty (1975a). That being said, if the points are close together, the results should. Contribute to AhiyaHiya/haversine development by creating an account on GitHub. Don't forget to convert degrees to radians. For any two points on a sphere, the haversine of the central angle between them is given by: Where. Add this topic to your repo. Now one is ready to apply the haversine formula. c. GPS. Luckily, you don’t need to do the calculation by hand. It has many practical applications, including finding the. MySQL geospacial search using haversine formula returns null on same point. The haversine of the angular length of the third side equals the haversine of the difference between the angular lengths of the first and second sides plus the product of the haversine of the angle. For your application, Vincenty may be a "better". Remember. Aug 31, 2012 at 22:41. To consider that Earth is a oblate spheroid consider using Vincenty's formulae. Hàm initialize () được gọi khi trang được tải, nó được xây dựng nhằm mục đích khởi tạo và cấu hình ban đầu. 0761803876This JavaScript uses the Haversine Formula (shown below) expressed in terms of a two-argument inverse tangent function to calculate the great circle distance between two points on the Earth. How to alter the Haversine formula to calculate distance between fixed point and user's location. -. cdist (all_points, all_points, get_distance) As a bonus you can convert the distance matrix to a data frame if you wish to add the index to each point:I am using the Haversine formula to calculate a distance in miles between two (lat, lng) coordinate pairs. To see why this function is useful, put yourself in the shoes of an. intermediate result c is the great circle distance in radians. Contribute to njj/haversine development by creating an account on GitHub. The Haversine formula is used to calculate the distance. The distance problem can be solved by using the Haversine formula. 2 miles or 6,378. Android - Calculate Distance Using Haversine Formula (Using GPS , Lat and Long) 2. cos (lat_1) * math. For any two points on a sphere, the haversine of the central angle between them is. The haversine formula is an equation important in navigation, giving great-circle distances between two points on a sphere from their longitudes and latitudes. It's an application of a more general trigonometric law for relating points on a spherical surface. " Learn more. Combine already present Geo coordinates with the new ones. Assuming that you want to compute haversine () with the first element in each user id group against all the other entries in a group, this approach will work: # copying example data from OP import pandas as pd df = pd. Problem can be solved using Haversine formula: The great circle distance or the orthodromic distance is the shortest distance between two points on a sphere (or the surface of Earth). Task. 83171, 36. 291994, 36. For some reason this only works in the northern hemisphere and I'm suspecting its because of the abs. sin (d_lng / 2) ** 2 ) return. Q: Is it true that Haversine's formula returns a maximum porcentual difference of 0. Pandas: calculate haversine distance within each group of rows. public class DistanceAlgorithm { const double PIx = 3. I need to write a program module to calculate distances given longitude and latitude data. I am using the Haversine formula to generate my distance calculations and that seems to be working accurately. Given two points on a sphere and θ being the flat angle between radii connecting those points with the center of the sphere, the haversine formula expresses the haversine function with the lattitude (φ) and longitude (λ) values of those points. Here's a refactored function based on 3 of the other answers! Please note that the coords arguments are [longitude, latitude]. Does anyone know how to make it to C# code when user input latitude and longitude of two places, and find out the distance between them. The dimension of the data must be 2. d = 2Rarcsin√sin2Δφ 2 + cosφ1cosφ2sin2Δλ 2. MySql spatial data query for finding near locations using haversine formula. lng, v. Reload to refresh your session. java distance earth geodesy haversine meters azimuth haversine-formula vincenty bearing midpoint vincenty-formula geocalc standpoint Updated Oct 24, 2020; Java; maurycyp / vincenty Star 58. Add this topic to your repo. g. As in the case of numerical vectors, pdist is more efficient for computing the distances between all pairs. dlon = lon2 - lon1 dlat = lat2 - lat1. Multilanguage (C#/Matlab/Rust) library for solving navigation (2D/3D) & geodetic problems: Multilateration (true range), Time-Of-Arrival (TOA), Time-Difference. MySQL geospacial search using haversine formula returns null on same point. Performance Centres of Asia. What you can do, is break the entire route into. Remember. The distance d ≃ 12, 469km. The haversine formula 1 ‘remains particularly well-conditioned for numerical computation even at small distances’ – unlike calculations based on the spherical law of cosines. I transformed the distance calculation (Haversine formula) into a DAX measure (Distance measure). cos(lt2). 8391) ) * cos ( radians ( lat ) ) * cos ( radians ( lng ) - radians (4. import math def get_distance (lat_1, lng_1, lat_2, lng_2): d_lat = lat_2 - lat_1 d_lng = lng_2 - lng_1 temp = ( math. The formula is given below. Using the Haversine Equation. e cos a = cos b * cos c + sin b * sin c * cos A. 2 m). We consider two characters from and as matching if they are the same and not farther than characters apart. Where (x => new GeoCoordinate (longitude, latitude). In reality Salesforce uses the haversine formula to calculate the great-circle distance between two points. The vectors from the center of the sphere to the vertices are therefore given by , , and . The Haversine (or great circle) distance is the angular distance between two points on the surface of a sphere. I'm calculating the distance between 33. Worst case is, k-means will never converge!C# . 3. It’s used to calculate the shortest distance between two points on the Earth’s surface. The haversine formula, generalized, is: Distance Using Haversines. $^{1}$ To convert right ascension given in hours, minutes and seconds and declination, given in degrees, minutes and seconds, to radians you do $$alpha = (RAh*15 + RAm/4 + RAs/240) imes pi/180$$ $$delta = (DEd pm DEm/60 pm DEs/3600) imes pi/180,$$ where in the latter formula you use plus signs for objects in the northern. $\begingroup$ At first I was thinking that it might be possible to scrape the Haversine formula and just compute the Euclidean distance between the two points -- I guess that would work for most cases since the data points have randomly generated altitudes between 0 and 1200 miles. I can't use math methods in Java-1. Note how the second formula expands the apparent x-displacement (by virtue of dividing by a number less than 1. Multilanguage (C#/Matlab/Rust) library for solving navigation (2D/3D) & geodetic problems: Multilateration (true range), Time-Of-Arrival (TOA), Time-Difference-Of-Arrival (TDOA), Angle-Of-Arrival AOA (Direction-Of-Arrival, DOA); Direct & inverse geodetic problems: Vincenty equations, Haversine formula; Virtual Long Baseline navigation. . El haversine del ángulo central (que es d/r) se calcula mediante la siguiente fórmula: donde r es el radio de la tierra (6371 km), d es la distancia entre dos puntos , es la latitud de los dos puntos, y es la longitud de los dos puntos respectivamente. Hashes for haversine-2. The following query would return documents from the places collection within the circle described by. ; Cosine Similarity: It measures the angular cosine similarity between 2 vectors. If you are installing through anaconda prompt remove the “!” mark from the above command. Below is the implementation of above idea. sql-server × 9. How to apply the Haversine formula. The flat earth formula will be much faster than the haversine. Versions Compatible and additional computed target framework versions. More than 100 million people use GitHub to discover, fork, and contribute to over 330 million projects. . Related. In summary, the haversine formula is an approximation that assumes a spherical Earth, but there is a 21 km difference between the equatorial and polar radii. g. atan2 (). Now one is ready to apply the haversine formula. 球面三角法（きゅうめんさんかくほう、英: spherical trigonometry ）とは、いくつかの大円で囲まれた球面上の図形（球面多角形、とくに球面三角形）の辺や角の三角関数間の関係を扱う球面幾何学の一分野である。 球面上に2点A,Bがあるとき、この2点と球の中心を通る平面で切断した. Pow (Math. I'm using simplified formula: // cos (d) = sin (φА)·sin (φB) + cos (φА)·cos (φB)·cos (λА − λB), // where φА, φB are. INSTRUCTIONS: Enter the following: (Lat1) Latitude of. Implement a great-circle. Sinnott, "Virtues of the Haversine" Sky and Telescope, vol 68, no 2, 1984First, convert the radius r into degrees as if you were located near the equator. This question came to us in 2001: Deriving the Haversine Formula I'm an SAS programmer at The Coca-Cola Company. Let’s have a look at the haversine formula: a = sin²(Δφ/2) + cos φ1 ⋅ cos φ2 ⋅ sin²(Δλ/2) c = 2 ⋅ atan2( √a, √(1−a) ) Distance = R ⋅ c Vincenty's formulae. Now simply apply the following formula, where φ stands for latitude and λ longitude. But how i can find distance between three or more lat/lon points? Example haversine formula for two points: // C# program for the have. So why is there a 1% difference in the answer given by Google's spherical computeDistanceBetween and the Haversine distance formula? – Matt S. 4081/W (LA Airport) and 20. Snowflake recommends using the. It is a special case of a more general formula in spherical trigonometry, the law of haversines, relating the sides and angles of spherical "triangles". Second, after generating x and y as in step (1), adjust the x-coordinate for the shrinking of the east-west distances: x' = x / cos (y0) The desired random point is at location (x'+x0, y+y0). Working with atan2. Remove any null coordinates. 315949) Do compute the distance with the above written formula. 1. The haversine formula is an old equation used by navigators before the invention of modern-day navigation systems. Now, the angular lengths of the sides of the triangle (in radians) are then , , and , and the actual arc lengths. 5. The ‘(re)versed sine’ is 1−cosθ , and the ‘half-versed-sine’ is (1−cosθ)/2 or sin²(θ/2) as used above. It is a special case of a more general formula in spherical trigonometry, the law of haversines, relating the sides and angles of spherical "triangles". The Haversine formula is used to find the distance between two geographical locations. It gives the shortest distance between the two yellow points. The haversine formula is an equation important in navigation, giving great-circle distances between two points on a sphere from their longitudes and latitudes. The ‘(re)versed sine’ is 1−cosθ , and the ‘half-versed-sine’ is (1−cosθ)/2 or sin²(θ/2) as used above. It is a special case of a more general formula in spherical trigonometry, the law of haversines, relating the sides and angles of spherical "triangles". 5mm (not metre, half a millimetre) instead of 0. This is a just a port of heycarsten 's Haversine class in Objective-C. Add this topic to your repo. I am not sure the answer is suitable for my needs, although the Haversine formula is useful to know. The formula in this library works on the basis of a spherical earth, which is accurate enough for. from. PI; However, atan2 let's the angle increase in CCW direction. La fórmula de Haversine es la siguiente: Fórmula de Haversine. Haversine is More Faster. In order to obtain the haversine formula of the previous section from this law, one simply considers the special case where u is the north pole, while v and w are the two points whose separation d is to be determined. MySql spatial data query for finding near locations using haversine formula. I have already looked into the haversine formula and think it's approximation of the world is probably close enough. js. When the two points are antipodal (on opposite sides of the Earth), the Haversine Formula is ill-conditioned (see the discussion below the Law of Cosines for Spherical Trigonometry), but the error, perhaps C++ implementation of the Haversine formula. . d = 2r * arcsin (sqrt (sin² ( (lat2-lat1)/2) + cos (lat1) * cos (lat2) * sin² ( (lon2. python spatial-analysis haversine latitude longitude spatial-data haversine-formula distance-calculation vincenty vincenty. hav (Θ)는 하버사인 함수로 다음과 같이. Since tables of natural haversines and their logarithms are available, the cosine formula may be rearranged in more suitable form for solution by loga-rithms. 887 1 1 gold badge 9 9 silver badges 18 18 bronze badges $endgroup$ 13. How to check if coords are within a radius in km? 1. SELECT v. With lat/lon data, ArcGIS is using a geodesic calculation (roughly Vincenty). 9425/N 118. The formula here is in kilometres, you will have to change the relevant numbers and it. Improve this answer. It is a special case of a more general formula in spherical trigonometry, the law of haversines, relating the sides and angles of spherical "triangles". 공식은 다음과 같습니다. The intermediate result c is the great circle distance in radians. As pointed out in comments, is there a generalization of the Haversine formula? geometry; Share. 1. I'm using the following query to get all the locations within a 25km radius. About 3% of latitudes have this problem; example: 60. 5k. from math import cos, sin, atan2, radians, sqrt def findDistance (p, p2): R = 3959 lat1 = radians (p [0]) lon1 = radians (p [1]) lat2 = radians (p2 [0]) lon2 = radians (p2 [1]) dlat =. After installing the library import it. The haversine formula is an equation important in navigation, giving great-circle distances between two points on a sphere from their longitudes and latitudes. If you have an accuracy sensitive application keep in mind the Haversine formula does not guarantee an accuracy better then 0. 半正矢公式是一种根据两点的经度和纬度来确定大圆上两点之间距离的计算方法，在導航有着重要地位。 它是球面三角學中“半正矢定理”公式的特例，该定理涉及了球面三角形的边和角。. Task. g. On my site I'm trying to get locations nearby. The Haversine formula is more robust for the calculating the distance as with the spherical cosine formula. Task. This is the formula: I am not sure why but my program is not working. (18) becomes indeterminate over equatorial lines (since cos²α → 0); in this case, set cos2σ m to 0 and the result is computed correctly. It uses the Haversine formula to calculate the distance based upon the supplied GPS coordinates. the code kindly suggested by blah238. Important in navigation, it is a special case of a more general formula in spherical trigonometry, the law of haversines, that relates the sides and angles of spherical triangles. PI / 180; } var lon1 = coords1 [0]; var lat1 = coords1 [1]; var lon2 = coords2 [0]; var lat2 = coords2 [1]; var R = 6371. GeoCoordinate)' method, and this method cannot be translated. Any errors are probably mine. c. name, p. The resulting formula has just one trigonometric call, making it much faster than the trigonometry-heavy Haversine formula. 44 5 5 bronze badges. A C# class library that will calculate distance and cardinal direction between two sets of coordinates and provides the lat/long boundaries around an origin coordinate allowing for simple SQL or LINQ selection of locations within the given radius. Task The Haversine formula is perhaps the first equation to consider when understanding how to calculate distances on a sphere. Implement a great-circle. Now for the C code! To convert this code, there were three things I had to do to implement this as C code: A. This seemed like an excellent opportunity to create a. We would like to show you a description here but the site won’t allow us. Here my code I used below code to calculate the distance between two location using their latitude and longitude. Or, if you are using SQL Server 2008, then geospatial support is built-in. The haversine formula determines the great-circle distance between two points on a sphere given their longitudes and latitudes. As with anything "better" is a matter of your particular application. The great-circle distance calculation also known as the Haversine formula is the core measure for this tutorial. atan2 is a common function found in almost all. The calculation can be done by computer, or by hand via tabular methods and longhand methods. Follow. While more accurate methods exist for calculating the distance between two points on earths surface, the Haversine formula and Python implementation couldn’t be any simpler. The haversine formula is an equation important in navigation, giving great-circle distances between two points on a sphere from their longitudes and latitudes. The haversine formula determines the great-circle distance between two points on a sphere given their longitudes and latitudes. Input them in the haversine distance formula: d = 2R × sin⁻¹ (√ [sin² ( (θ₂ - θ₁)/2) + cosθ₁ × cosθ₂ ×. I am doing a silverlight bing map application. But there’s one more consideration. haversine. To associate your repository with the vincenty-formula topic, visit your repo's landing page and select "manage topics. If you master this technique, you can tackle any required distance and bearing calculation. NET UNTUK PROGRAMMER Panduan Lengkap dan Ringkas Pemrograman Database dengan Java/MySQL Tutorial Lengkap Excel Sampai Mahir The Complete Guide to. Overview In this tutorial, we study the definition and usage of the haversine formula for calculating the distance between two points on a spherical surface. To use the spreadsheet containing the Haversine equation, enter the latitude and longitude of your origination point in cells A1 and B1, in degrees. This formula is slightly different from the Power Query function because I just made this as a. distanceBetween(startLatitude, startLongitude,. λ1, λ2: 1지점과 2지점의 경도 (라디안 단위). Do not use the arithmetic average if you have the -180/+180. I have seen code for calculating distance using the haversine formula using C# etc on the site, but nothing using c++, so here is the code that just does that Background (optional) I saw couple fo articles doing thie distance calculation using the haversine formula but using . The haversine formula is an old equation used by navigators before the invention of modern-day navigation systems. lon1 = lon1 * PI/180 Convert the. The Haversine method gives an accurate way of determining the distance between any specified longitude and latitude. hamming (u, v [, w]) Compute the Hamming distance between two 1-D arrays. Google MapV2 Distance Calculation. 62miles. The Haversine calculator computes the distance between two points on a spherical model of the Earth along a great circle arc. float xDiff = x2 - x1; float yDiff = y2 - y1; return Math. 0. The haversine, also called the haversed sine, is a little-used entire trigonometric function defined by hav(z) = 1/2vers(z) (1) = 1/2(1-cosz) (2) = sin^2(1/2z), (3) where versin(z) is the versine, cosz is the cosine,. I tested the C# formula and it was spot on. It is a special case of a more general formula in spherical trigonometry, the law of haversines, relating the sides and angles of spherical "triangles". Task. The Haversine Formula in C# and SQL: Distance between two points Storm was recently asked to create a local office finder for a client. To associate your repository with the haversine-formula topic, visit your repo's landing page and select "manage topics. sin (), math. θ = Angle introduced at the center of the Earth by the two addresses. The great circle method is chosen over other methods. Vincenty is more accurate but is also more computationally intensive and will therefore perform slower and increase battery usage. The sphere in this case is the surface of the Earth. whl; Algorithm Hash digest; SHA256. Implement a great-circle. so. 1. It takes into account the curvature of the Earth’s surface and provides more accurate results than simply calculating the Euclidean distance between two points. So my question is, which one produces better results either haversine or geodesic distance?See Haversine or even better the Vincenty formula how to solve this problem. var earth = 6378. All 9 Python 4 C 2 Jupyter Notebook 2 C# 1. Known as the Haversine formula, it uses spherical trigonometry to determine the great circle distance between two points. 5% as it is assuming the earth is a sphere. To see why this function is useful, put yourself in the shoes of an. r é o raio da esfera. matPara calcular la distancia entre dos puntos con coordenadas, se utiliza la fórmula de Haversine. Haversine in C#: Calculate the distance between two points along the surface of a sphere. gov ) of Caltech and NASA's Jet Propulsion Laboratory as. There are several related functions, most notably the coversine and haversine. answered May 12, 2012 at 0:04. So you need a point on the polygon which has the nearest distance to the point. Get the Range of Lat Long with in specified Radius in c#. SELECT id, ( 6371 * acos ( cos ( radians (51. The haversine formula determines the great-circle distance between two points on a sphere given their longitudes and latitudes. Supports all endpoints and requests / responses. Geographic coordinate distance calculation with haversine formula gives the wrong output. Latitude)) <= radius); And got: LINQ to Entities does not recognize the method 'Double GetDistanceTo (System. In summary, the haversine formula is an approximation that assumes a spherical Earth, but there is a 21 km difference between the equatorial and polar radii. where:into other forms. lat <= 1. So I'm trying to use the haversine formula in Unity to get the distance between two different points (latitude and longitud given). For example, the Cartesian formula for distance (Pythagoras) involves one call to sqrt(). Under these conditions, the Haversine Formula is ill-conditioned (see the discussion below), but the error, perhaps as large as 2 km (1 mi), is in the context of a distance near 20,000 km (12,000 mi). Add the following lines after the markers in the. The haversine formula 1 ‘remains particularly well-conditioned for numerical computation even at small distances’ – unlike calculations based on the spherical law of cosines. 504048, Longitude : -98. It calculates the distance between the two coordinates using the Haversine formula for calculating distances on a sphere. The distance between two points in Euclidean space is the. ) It all stems from the fact that a line between point a and point b on a globe isn't a line at all, it is an arc. The simplest way to use this (or a more accurate, but I think it's not your case) formula consists into press Alt+F11 to open the VBA Editor, click Insert --> Module and then (copy and) paste e. 5544. NET Core Google Api (Maps, Places, Roads, Search, Translate). The haversine formula is an equation important in navigation, giving great-circle distances between two points on a sphere from their longitudes and latitudes. Implement a great-circle. Learn more… Top users; Synonyms. 球面三角形. 0. However, even though Vincenty's formulae are quoted as being. . Therefore the. This formula is seldom derived. Basically in all lat/lon problems you are dealing with great circle distances (which is just a fancy term for a spherical system of coordinates over the earth's surface. Task. The Haversine calculator computes the distance between two points on a spherical model of the Earth along a great circle arc. Why does the change in heuristics cause it to be more accurate, and take longer to run? The first heuristic, distance squared, overestimates the real distance (by a lot, depending on the situation) even though the actual distance is computed the same way, because the actual distance is computed as the sum of single steps (the sum of squares. It's been a long, long time since I have had to use trigonometry. Important in navigation, it is a special case of a more general formula in spherical trigonometry, the law of haversines, that relates the sides and angles of spherical. Note. Here is a comparison of the two formulas using 100 random point-pairs on the globe (using Mathematica's double-precision calculations). 5:1-5 John is weeping much because only Jesus is worthy to open the book. This method assumes the Earth is a perfect sphere. Where: s is the geodesic distance along the surface of the ellipsoid (in the same units as a & b); α 1 is the initial bearing, or forward azimuth; α 2 is the final bearing (in direction p 1 →p 2); Note: Vincenty observes that eqn. 0-py2. cdist. Input them in the haversine distance formula: d = 2R × sin⁻¹ (√ [sin² ( (θ₂ - θ₁)/2) + cosθ₁ × cosθ₂ ×. Connect and share knowledge within a single location that is structured and easy to search. The Haversine formula is nice and fast, but it has a ‘fatal’ flaw of returning NULL sometimes when measuring the distance between a point and itself. Hot Network Questions How to ensure data consistency in system with multiple databases?Then the haversine formula calculates the distance between the two places. The word "Haversine" comes from the function: haversine (θ) = sin² (θ/2) The following equation where φ is latitude, λ is longitude, R is earth’s radius (mean radius = 6,371km) is how we translate the above. c# × 10. In this article, we saw three ways to calculate the distance between two geographical points in Java. I've also tried to invert the formula, but have gotten stuck halfway. However the formula with haversine is more accurate. Cite. Did you know how google maps measures distance from one location to another? Watch this short video on ho. The function takes two coordinates as input, each consisting of latitude and longitude values. We'll call θ and φ to their respective latitude and longitude components. e. 半正矢公式.