Google have been recording the location of my android phone every time it talks to their servers for the past year. It talks to their servers a lot.
Locations I (or rather my phone) have been in Colorado:
23 Monday May 2016
Posted Geo data
inGoogle have been recording the location of my android phone every time it talks to their servers for the past year. It talks to their servers a lot.
Locations I (or rather my phone) have been in Colorado:
13 Friday May 2016
Posted Geo data
inTo celebrate my 100th flight (DCA to DEN, as you ask), here’s an update to my flight map.
06 Monday Jul 2015
Posted Geo data
in08 Monday Jun 2015
Posted Geo data
inTo overlay two countries, move them so that their centres are over the same point (eg 0, 0). The trick is to make sure that they stay the same size, and don’t get too distorted in the process.
The jamegeo.com country comparison method is:
1. Re-project your country into a UTM zone. This means that you can translate (move) it North or South without enlarging / shrinking the country, or distorting the shape. This only works if your country fits inside one UTM zone… which almost none do.
2. Move the country until the centre sits on the equator. Expect minor change in shape if your country is too fat for its UTM zone.
3. Re-project into a Equirectangular projection (eg WGS84)
4. Move your country along the equator, which you can do in a equirectangular projection without altering the shape.
5. Rescale (a very little bit) to compensate for any shrinking during stage 2.
6. Combine with another country and be very pleased with yourself.
25 Monday May 2015
Posted Geo data
inTags
Which is bigger, Australia or USA?
By USA we mean the contiguous states.
I forget who asked, but judge for yourself!
This construction image has a certain elegance to it:
11 Monday May 2015
Posted Geo data
inTags
We’ve previously seen that our Air Safaris Scenic flight was close to the advertised flight path. To add some 3D information I’ve found a 8m DEM.
I’ve used the QuantumGIS 2threejs plugin to show the side view – both the flight and terrain data are now in three dimensions.
Now that we have a DEM, we can drape any imagery over the top.
27 Monday Apr 2015
Posted Geo data
inImagine there’s no countries.
It isn’t hard to do.
Imagine unioning all of the countries (turning all of the separate shapes below into one) … it turns out to be harder than I thought.
Which brings to mind a favourite saying of another Beatle:
Peace and love,
Peace and love
Thanks, Ringo.
30 Monday Mar 2015
Posted Geo data
inTags
In February Jamesgeo Team NZ flew on Air Safaris’ Grand Traverse and took lots of photos. For the record, this was an excellent experience. The Air Safaris guide shows the proposed flight path… but where did we really fly?
I have used QuantumGIS’s georeferencer plugin to turn the above image into a map by identifying a number of Ground Control Points (GCPs), such as Lake Tekapo airport, Glentanner Park and various road junctions. This results in a georectified (and georeferenced) image, displayed in WGS84, the coordinate reference system of the GPS points used as the GCPs.
I made a new postgreSQL table with columns for both 2D and 3D geometries, then inserted each point (see bottom of page for SQL commands). This gives us 1410 points, coloured here by altitude. I have reprojected the map into the New Zealand map grid (EPSG:27200).
Displaying this route on top of the Air Safaris map:
So our blue track is pretty close to the advertised red track. Well done Air Safaris!
16 Monday Mar 2015
02 Monday Mar 2015
Posted Geo data, Populations
in