as we known,the GPS sensor gets the longitude and latitude, but the value is not accurate, for example,the car's speed will be 0km/h when the car waiting the traffic lights. the longitude and latitude will around the car. how can i use apache.math Kalman to solve this?
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Hello there's I am use google's Heatmap feature in my project. I do not know whats the maximum points (latitude ,longitude )limit for google's heatmap to visualization.
There is no limit to the number of points added to the heatmap, but there are practical constraints (the memory of the device displaying them, the time to load them, etc.)
Longitude is in the range -180 and +180 specifying coordinates west and east of the Prime Meridian, respectively. For reference, the Equator has a latitude of 0°, the North pole has a latitude of 90° north (written 90° N or +90°), and the South pole has a latitude of -90°.
The limit is for longitude and latitude not for google heatmap feature for using latitude or longitude. If your latitude/longitude is in valid range , it will work.
All of my lat/lng locations have been taken off of Google Earth using the mouse.
When I enter the data into Google Maps I have multiple instances where the marker does not show the proper location. For example: a marker for lat 38.015986 lng -84.355413 (coordinates for The Aviation Museum of Kentucky) shows up at 38.005754, -84.211968 (again using my mouse pointer to provide lat/lng of marker.)
I can't use geocode because many of my locations do not have addresses - in road medians, internal to 430 acre park, etc.
How do I correct for (or get) the proper lat/lng?
Possibly you have the units of your Lat Long incorrectly entered.
Lat and long can be entered as
hdd.ddddd (decimal degrees)
hddd'mm.mmm' (degrees with decimal minutes)
hdd'mm'ss.ss'' (degrees, minutes seconds)
This seems likely, since you get close to the correct answer.
If you need to convert between these or any positional grid system and datum I recommend using Garmin Basecamp, it is free.
NOAA gives a Polygon area for plotting shapes on a map. The only thing I can find in google maps is to use a lat/lon to create a shape.
You can view the warnings here with their polygons:
http://www.nws.noaa.gov/regsci/gis/last10.html
Can somebody please tell me what these 4 digit numbers represent and if it's possible to convert them to a latitude / longitude.
The numbers are hundredths of degrees. A 4-digit number is latitude, so for instance 3503 represents 35.03 degrees North latitude. A 5-digit number is longitude, so 10581 would be 105.81 degrees West longitude.
I'm working on a simulator that plots the flight path of an aircraft on Google Maps.
The simulator is not aware that the latitude is only defined between -90 and +90 degrees and the longitude between -180 and +180 deg. As a result of this, the flight path may include points beyond the map boundaries. Exceeding in longitude is not an issue as it still plots correctly (a point at longitude x and x+360 is the same), but the latitude is a problem.
Is there any way of telling Google Maps to keep the points between the correct boundaries and plot them correctly?
Otherwise, do you have any ideas of where to find functions that do so?
Longitude, latitude and elevation are a bad coordinate system for a flight simulator, because the mapping presents singularities i.e. there are points infinitely close on the earth that have very different coordinates. For example where you're close to one of the poles longitude variation speed can become arbitrarily big compared to airplane speed. When standing exactly on the pole the longitude doesn't even make sense.
A better solution is to use an XYZ coordinate system for the simulator and only convert to longitude/latitude and elevation for plotting. If you can approximate the earth to a sphere for your use case the computation of this transformation is trivial... otherwise things can get much more complex depending on how accurate you want it to be.
That said it's still possible to give "a" meaning to a point with latitude slightly outside the range -90...90 by extending it over the pole...
if latitude < -90:
latitude = -180 - latitude
longitude = longitude + 180
if latitude > 90:
latitude = 180 - latitude
longitude = longitude + 180
but using this coordinate system for navigating is a very bad idea (the same point in space can have multiple triplets of coordinates).
If your simulator doesn't know that the maximum value for latitude is 90 degrees it is broken and needs to be fixed. Google Maps works correctly for valid/possible values of latitude and longitude.
I have a MySQL table with cities, and for each city I have the geo coordinates. I want to build a query that determines the nearest city given coordinates of any random position. Can anyone give me an example?
Maybe I misunderstood the question, but if you have:
[X1,Y1] - the coordinates of your position
[Xn,Yn] - for each city
Then why not just calculate the distance using the simple sqrt((X1-Xn)^2 + (Y1-Yn)^2) formula?
You could optimize it further be making some clever selects, to only get the vicinity of the position from the DB and then run the distance measuring on these cities.
http://www.davidus.sk/web/main/index/article_id/8
There you go, distance is actually a radius. It will return all cities within it.