search location by latitude and longitude

DLL, Microsoft.SqlServer.Types.dll . This is a managed DLL, which means that. NET C # ASP can also use some features.For example by reference reference: Microsoft.SqlServer.Types.dll this DLL.var a = Sqlgeography.point (22.54587746114.128730774326// some point in Shanghai var b = Sqlgeography.point (at some point in4326// Shanghai, 4236 represents the WGS84 coordinate reference system. // distanceThis calculated distance, with the above using the Haversine formula calculated distance, the err

SQL statements: Select Location.* from (select *,round (6378.138*2*asin (sqrt () (Pow () (Sin (36.668530*pi ()/180-px_lat*pi ()/180)/2), 2) +cos (36.668530*pi ()/180) *cos (Px_lat*pi ()/180) * POW (Sin ((117.020359*pi ()/180-px_lon*pi ()/180)/2), 2)) (*1000)) As distance from bsx_training where (px_state = 1) and (type_id! = ") and (((Px_lat >= 27.683290277922) and (px_l At Ignore the above SQL statement first. One by one explanationSQL statements so

Baidu Map provides a range of search capabilities, but it uses Baidu's own data, but sometimes we need to use their own data, displayed on the map. For example, given two parameters: Specify a location (latitude and longitude Lnglat at one point) and search radius (r) to

ad= 2*sin (DLON/2) *cos (LAT1), similar can be introduced CB length = Cb=2*sin (DLON/2) *cos (LAT2)Now look at how to find the length of AB, back to the plane isosceles trapezoid, such as:(Fig. 3)Ah is the vertical line to the CB (perpendicular), ch= (CB-AD)/2.According to the Pythagorean Theorem (Pythagorean theorem): "^2 represents 2 squared"ah^2 = ac^2-ch^2= ac^2-(cb-ad) ^2/4The length of the HB is Hb=ad+ch = AD + (cb-ad)/2 = (CB+AD)/2, which is obtained according to the Pythagorean theorem:

This article mainly introduces about PHP according to latitude and longitude sorting, according to latitude and longitude to filter the distance segment, has a certain reference value, now share to everyone, the need for friends can refer to SQL statements: Select Location.

longitude and latitude as hash. The question is rough. I can only tell you about my method in general, and I have done something similar.1. Store the merchant's location information in segments according to the city,2. the browser obtains the user location and uses Baidu's map js api.3. Calculate a rectangle center

Baidu provides the query latitude and longitude of the API is: Http://api.map.baidu.com/geocoder?address= the address you want to query output=xmlkey= the key you want to enter A ready-made key is: F247CDB592EB43EBAC6CCD27F796E2D2 returns JSON We take the longitude and latitude information of Xi ' an as an example: Ad

GPS is converted into a hundred degrees longitude and latitude, and gps is converted into Baidu longitude and latitude Recently, Baidu's api is used for map positioning. Baidu's background sometimes stops to obtain the longitude and lat