Mapping data drawn from a mySQL database

Previous examples of web maps generated using Leaflet have relied on GeoJSON files for their overlay data. Here data is extracted from a mySQL database containing some UK crime data. The data was downloaded from the Police website as a CSV file and then imported into mySQL using the Table Data Import Wizard in the mySQL Workbench. I would have preferred to use PostgreSQL, it’s more familiar, but my hosted web space only offers mySQL. Continue reading “Mapping data drawn from a mySQL database”

Metrolink for Oxford Road?

The “Wilmslow Road corridor” in Manchester is reputedly the busiest bus route in Europe, carrying thousands of students from the south of the city into the city centre and the two universities. A section of the route, from Rusholme to the city centre, is currently being transformed into a bus priority route with extensive “Dutch-style” segregated cycle lanes. The current works have exposed some of the history of the city’s earlier transport network. These images taken near the John Dalton Building, MMU show the exposed cobblestones and old tram tracks. Continue reading “Metrolink for Oxford Road?”

Holiday in Berlin

Berlin tourist map
Berlin tourist map

This post is one of a series on web mapping.

When in Dresden a few years ago I bought an old map of Berlin in a flea market.  Dated 1966, it was produced by Landkartenverlag Berlin, in the former DDR, who specialised in producing tourist maps.  It has a partial view of the city. Partial in both senses, since it omits any detail of West Berlin or “Territories  under US, British and French Occupation“.  The only features mapped in the West are S-Bahn stations (labelled) and major roads (unlabelled). Continue reading “Holiday in Berlin”

Debugging JavaScript with the Atom editor

JavaScript is not easy to debug. This is particularly the case when we try to “hack” some existing code for our own purposes rather than write the code from scratch, carefully checking each bit of code as we add it. We cut and paste and chop and change without fully understanding the intricacies of the code – no shame in that, of course, this technique has fuelled 20+ years of web development. Continue reading “Debugging JavaScript with the Atom editor”

Network checking with QGIS

I’ve recently been doing some work with town and city road networks in the UK using the Ordnance Survey ITN network dataset. For each town I have been using its boundary, as defined in the UK Census, as a “cookie cutter” for the network. Unfortunately this can lead to an untidy network:

  • nodes without links (A below)
  • links without end nodes (B below)
  • disconnected “islands” (C below)

Continue reading “Network checking with QGIS”