geography

Creating an abitrary, curved Well Known Text LineString for display in OpenLayers

由 谁都会走 提交于 2019-12-08 02:53:32
问题 I am dynamically generating a WKT LineString between points in a map layer being generated for display in OpenLayers. I'd like to make the lines between the points curved, and I'd like to be able to dynamically change the curvature based on various input variables. This is for a network monitoring app, and we'd like the curvature to based on delay times between the points (not the raw delay itself, but the deviation from "normal" values during a given time period). While some GIS app and

Distance between lat/long points using the haversine formula

由 只谈情不闲聊 提交于 2019-12-07 14:26:43
问题 I am trying to find the distance between two longitude and latitude points. I am trying ot use the great circle distance. This is the formula: I am not sure why but my program is not working. This is the result I am getting: Change Angle: 0.00016244370761414 Earth Radius: 6371 RESULTS: Correct Distance: 24.883 km Computed Distance: 1.0349288612097 Source: $latStart = 44.638; $longStart = -63.587; $latFinish = 44.644; $longFinish = -63.597; # Convert Input to Radians $latStart = deg2Rad(

Maximum length of a decimal latitude/longitude Degree?

由 会有一股神秘感。 提交于 2019-12-07 06:08:57
问题 What is the maximum length (in kilometers or miles - but please specify) that one degree of latitude and longitude can have in the Earth surface? I'm not sure if I'm being clear enough, let me rephrase that. The Earth is not a perfect circle, as we all know, and a change of 1.0 in the latitude / longitude on the equator (or in Ecuador) can mean one distance while the same change at the poles can mean another completely different distance. I'm trying to shrink down the number of results

Good GIS Software or Components for Windows PC in .NET? [closed]

由 允我心安 提交于 2019-12-07 04:54:48
问题 Closed. This question is off-topic. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed last year . Last week i searched for good free or opensource solutions and component for GIS (Geographical Information Systems) I founded some system but no one fill my requirements SharpMap is very buggy software Gmap.net is very slow MapWindow have a very complex structure and is very buggy. I founded uDIG but is in java, i

SQL Server Geography Point

由 。_饼干妹妹 提交于 2019-12-06 14:35:03
I have recently been researching the SQL Server spatial data types and have decided to try and store my long, lat points in a geography field. However I cannot figure out how to insert the data into the field, I have tried using stuff like "POINT(double, double), 0" and weird stuff like that, but no success. Also im curious as to what the purpose of the ID argument specified in the geography functions. Thanks, Alex. Have you looked at the examples from MSDN? From geography (Transact-SQL) : IF OBJECT_ID ( 'dbo.SpatialTable', 'U' ) IS NOT NULL DROP TABLE dbo.SpatialTable; GO CREATE TABLE

Determining cardinal (compass) direction between points

由 可紊 提交于 2019-12-06 07:43:21
问题 Is there a way to know in SQL Server 2008R2 if a point is at the south,east,etc...of another point? For example, I have an origin point(lat1,lng1) and I want to know where point(lat2,lng2) is located from that origin: north, west,etc... I'm trying to construct a wind rose graph and this might be useful to me. 回答1: In order to calculate the bearing between two coordinates while using the Geography type in SQL Server 2008 R2, you can use this function: CREATE FUNCTION [dbo].[CalculateBearing] (

Calculating shortest path between 2 points on a flat map of the Earth

由 ≯℡__Kan透↙ 提交于 2019-12-06 02:24:42
问题 How do you draw the curve representing the shortest distance between 2 points on a flat map of the Earth? Of course, the line would not be a straight line because the Earth is curved. (For example, the shortest distance between 2 airports is curved.) EDIT: THanks for all the answers guys - sorry I was slow to choose solution :/ 回答1: I get this sort of information from the Aviation Formulary. In this case: Distance between points The great circle distance d between two points with coordinates

Distance between lat/long points using the haversine formula

由 只谈情不闲聊 提交于 2019-12-05 20:48:50
I am trying to find the distance between two longitude and latitude points. I am trying ot use the great circle distance . This is the formula: I am not sure why but my program is not working. This is the result I am getting: Change Angle: 0.00016244370761414 Earth Radius: 6371 RESULTS: Correct Distance: 24.883 km Computed Distance: 1.0349288612097 Source: $latStart = 44.638; $longStart = -63.587; $latFinish = 44.644; $longFinish = -63.597; # Convert Input to Radians $latStart = deg2Rad($latStart); $longStart = deg2Rad($longStart); $latFinish = deg2Rad($latFinish); $longFinish = deg2Rad(

Good GIS Software or Components for Windows PC in .NET? [closed]

由 半腔热情 提交于 2019-12-05 09:22:11
Closed. This question is off-topic . It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed last year . Last week i searched for good free or opensource solutions and component for GIS (Geographical Information Systems) I founded some system but no one fill my requirements SharpMap is very buggy software Gmap.net is very slow MapWindow have a very complex structure and is very buggy. I founded uDIG but is in java, i need a solution in vb.net or c#. Anyone know a good solution that fill my requirements or have

Maximum length of a decimal latitude/longitude Degree?

由 南笙酒味 提交于 2019-12-05 08:27:27
What is the maximum length (in kilometers or miles - but please specify) that one degree of latitude and longitude can have in the Earth surface? I'm not sure if I'm being clear enough, let me rephrase that. The Earth is not a perfect circle, as we all know, and a change of 1.0 in the latitude / longitude on the equator (or in Ecuador) can mean one distance while the same change at the poles can mean another completely different distance. I'm trying to shrink down the number of results returned by the database (in this case MySQL) so that I can calculate the distances between several points
订阅 geography