I'd like to create a smart cache for my weather forecast API requests (temperature, wind, etc. for a given point).
I query the forecast provider by specifying coordinates of the point I want to get the data from. Sometimes, I query the same points over and over again or some nearby points and I'd like to make fewer requests to the forecast provider.
I thought about dividing the globe into tiles as they do on maps (eg. OpenStreetMap / Google Maps).
When the forecast is requested I would calculate the tile's x & y from the inputted coordinates and check if I have any recent forecast data stored in this tile.
Then:
If there are no points found, I would make a request to my forecast provider.
If a point is found in the requested tile, I would return that point's data.
After making a request to my weather forecast API provider, I would store the received data in my InfluxDB with a tile's x & y numbers and coordinates.
Is there a better way to cache it?
Related
I've got a database of points (in this case, schools) and in my app, users search for the nearest ones to them. Under the hood, we're currently using ElasticSearch to filter by latlng (using Geo Distance, which gets the distance as the crow flies. For the majority of places, this works fine, but in some coastal areas, this will pick up places that are impossible to get to, in the example below, a radius of 20 miles will pick up schools in Weston-Super-Mare, in reality 55 miles:
I initially decided to use the Google Maps Distance Matrix API to filter my inital as the crow flies search, but there's a limit of 25 destinations per query, and as the requests will be dynamic and user-facing, it's not practical to parcel these requests up into small pieces and pop in a background job.
Is there any way to carry out these calculations while accounting for bodies of water on a database level? The schools are stored in a Postgres database, so I thoughts about using PostGIS and some kind of point in polygon query, but I have no idea where to start looking.
Any ideas are very much appreciated!
I need to get travel time by plane between two locations.
In Distance Matrix API there is no Travel Mode like "flight" - https://developers.google.com/maps/documentation/javascript/distancematrix#travel_modes
Any suggestions?
Unfortunately there is no easy way to do this.
However, you could do a trick and estimate the flight time by using geocoding and the geometry library. At least if you don't need real flight data.
The steps would be:
Transform origin and destination from String to LatLng (Geocoding API)
Create markers for each location. (Geometry lib)
Calculate airline distance using computeDistanceBetween (like this: google.maps.geometry.spherical.computeDistanceBetween(path1, path2))
Calculate approximate flight time using average airplane speed.
Hope this helps.
This is sort of a work-around, but an easy one.
Use the measure distance tool in google maps, then for flight time of regular commercial airliners, divide the distance in miles by 500mph to get flight time in hours. For a small propeller plane (like a cessna), use 165mph.
anyone know, how to use google distance matrix Api but destination from webserver?
for example, i want to use google distance matrix api and latitude longitude destination from this url sempatbimbel.esy.es/actions/jsontbimbel.php
I know it is late. First, you need to get the IP address of this website (like ping in the ASP,PHP,....), then convert the IP to lat/long, something like this http://geoipinfo.org/ . Now, you have two sets of coordinates: Geo coordinates of the website and your destination.
then pass these geolocations to Google AP like this
https://maps.googleapis.com/maps/api/distancematrix/json?units=imperial&origins=40.6655101,-73.89188969999998&destinations=40.6905615%2C-73.9976592%7C40.6905615%2C-73.9976592%7C40.6905615%2C-73.9976592%7C40.6905615%2C-73.9976592%7C40.6905615%2C-73.9976592%7C40.6905615%2C-73.9976592%7C40.659569%2C-73.933783%7C40.729029%2C-73.851524%7C40.6860072%2C-73.6334271%7C40.598566%2C-73.7527626%7C40.659569%2C-73.933783%7C40.729029%2C-73.851524%7C40.6860072%2C-73.6334271%7C40.598566%2C-73.7527626&key=YOUR_API_KEY
from https://developers.google.com/maps/documentation/distance-matrix/intro
Given a square area, what is the best way to find the approximate coordinates of every street intersection within the given area ?
Since there is no description of your application, I can't tell if you need to use Google Maps or if another data source would answer your needs.
If http://openstreetmap.org fulfills the requirements of your application, then it's easy:
the OSM API has a request to pull data from a rectangular region. You get XML data.
filter this data to keep only the street you are interested in, probably the "key=highway" tags
filter this to keep only the points belonging to two or more lines.
Please disregard this if Google Maps is a requirement.
But still: since the roads exist independently of the database, the above method will yield roads intersections (in lat/long coordinates) with a pretty high correlation with what you would get from Google maps ;-) You can then use those points to display them over a Google map, knowing that both datasets aren't identical so it won't be perfect.
Might not be the easiest method but I used a seperate database of our countries roads with their linestrings.
I took the first and last points of each line string, then counted the number of roads within 50 m of each start/end point. I then took the nodes from navigation route and used these to compare the number of roads intersecting with each node. I then looked at the direction each start point and the next point along that road, which gives you direction. from that with a bit of maths you can work out the number and angle of the roads at the next intersection. I then made a road rules application that tells you which vehicles to give way to
Summary: I need a tool that can put 60m+ points on a map image. I'm trying to show density map and would like to plot a dot for each point (lat/long) on the map.
Hi I'm working on project that requires a density map. I have latitude and longitude and all the tools that I have seen (Ammap, FusionCharts maps, google charts/map) requires either XML or JSON or some other data type with the data points. Problem here is that, I have 60 million + data points and transferring any type of object with that many data point is not feasible.
One solution I can think of is mapping latitude and longitude to pixels of the map image. That requires a lot of time and work. I was wondering if you guys have done something similar and know of tools that can do this for me. It doesn't have to be free.
You'd be much better off creating a heatmap instead of passing all of the individual points to the map, which would get very busy, very quickly.
There are already a few discussions over at GIS.StackExchange about this exact topic. Search the the [heatmap] tag.
Since you mentioned FusionCharts, assuming you can load all of your data into a Google Fusion Table, it looks like you should be able to make a heat map in Google Fusion Tables).