latitude-longitude

问题 I'd like to drag an object into my Google Map (API V3) from outside the map. After some research, I found this very helpful post and I tried to adapt it to my project. The main idea is to drag a .png image on the map and when the mouse button is down, get the actual coordinates and place a marker at that lat / lng. But I noticed there is a difference between the point you drag your image and the point where your marker is placed. The difference is around 10 / 15 pixels on the sample linked

问题 How to get Latitude and Longitude for particular city or street or location without using google map? For example user entered city name is "Chennai" and i need to show only Latitude and Longitude for that city. How to do this? 回答1: This is called Geocoding, and requires matching a place name up to a latitude and longitude. You can either code a known list of place name/lat-lons into your app, read them in at runtime and search through them when required, or you can use an online Geocoding

问题 Does anyone know if there is a tool in R to find the height above sea level of a location, given the latitude and longitude ? 回答1: Or you can use the package that looks up from geonames, and get the value from the srtm3 digital elevation model: > require(geonames) > GNsrtm3(54.481084,-3.220625) srtm3 lng lat 1 797 -3.220625 54.48108 or the gtopo30 model: > GNgtopo30(54.481084,-3.220625) gtopo30 lng lat 1 520 -3.220625 54.48108 geonames is on CRAN so install.packages("geonames") will get it.

问题 ************* TrackGPS.java ***************************** import android.app.AlertDialog; import android.app.Service; import android.content.Context; import android.content.DialogInterface; import android.content.Intent; import android.content.pm.PackageManager; import android.location.Location; import android.location.LocationListener; import android.location.LocationManager; import android.os.Bundle; import android.os.IBinder; import android.provider.Settings; import android.support.v4.app

问题 I've got a dataset with latitude and longitude which I'd like to convert to the state plane coordinates for Illinois East, using EPSG 2790 (http://spatialreference.org/ref/epsg/2790/) or maybe ESRI 102672 (http://spatialreference.org/ref/esri/102672/). This has definitely been asked before; my code is based on the answers here ("Non Finite Transformation Detected" in spTransform in rgdal R Package and http://r-sig-geo.2731867.n2.nabble.com/Converting-State-Plane-Coordinates-td5457204.html).

问题 I have put together a cities database from MaxMind and it includes the lat/lng values for each city in the database. I have also put together a map of North/America and I would like to have a icon appear on the x/y coordinates of the map which are derived from the lat/lng coordinates of the city database record. From my understanding I need to find the left/top bounds of the map first (lat/lng -> x/y) and then use that as a difference for the linear relationship between any of the north

问题 I want to find the intersection points of two Locations in Android. I don't want to consider cases where the circles as shown in the Figure don't intersect or are included or are completely overlapping. My problem is that the Location is given in degree and the radius (accuracy) is given in meter. I do not know how to mix those Units. In my case the environment is Android, but the Problem is not Android specific. 回答1: You have to convert latitdue, longitude to a cartesian coordinate system,

问题 I need to write a background service to get latitude and longitude values. I have an Android application in which it has to find where the user is currently. Is there any way to programmatically get the latitude and longitude values from the system services (or some program)? 回答1: Use LocationManager . The documentation covers this. 来源： https://stackoverflow.com/questions/3640973/how-to-write-a-background-service-to-get-latitude-and-longitude

问题 Leaflet map How i get geo-coordinates( i.e latitude,longitude ) on every 1km/2km/(n)Km between two geolocation points. Image above for reference. 回答1: The "right way" to do this is to use geographiclib to fetch the azimuth and angular distance between the points; then fetch intermediate points by keeping the azimuth but specifying a different angular distance. Geographiclib is also able to calculate a point given an initial point, an azimuth, and a distance in meters. I suggest you first do a

问题 I have a csv of about 100 million logs. Where one of the column is address and I am trying to get latitude and longitude of the address. I want to try something like mentioned in the Solution , But the solution given is arcGIS and that is a commercial tool. I did try google API that has limit of 2000 entries only. What is next best alternative to get address's Lat & Long into the large dataset. Input: The column Site is the address from the City Paris start_time,stop_time,duration,input