The coordinate from Visum is based on real distance.
There are many different coordinates for various uses. In our case, the dataset has consisted of many big numbers base on x and y coordinate axis. They are not longitude and latitude value for geographic use, so we can’t use this data directly for Google Maps or Baidu Maps.
Universal Transverse Mercator System:
The idea of UTM is making a projection for the earth and then get the x,y coordinate. (Kinds of (0,0) all located in African.) More information, please visit this reference: http://www.ibm.com/developerworks/cn/java/j-coordconvert/
The following reference shows the difference among GCJ-02, WGS-84, and UTM. In this article, you can also find these coordinates system information that main map companies use. http://www.cnblogs.com/milkmap/p/3627940.html
Baidu Maps issue: UTM to Baidu Coordinate http://my.oschina.net/webscraping/blog/511029?fromerr=k3LHV5MM
The original data is close to Universal Transverse Mercator system. So I decided to convert the dataset into UTM first.
Firstly, we have to get the UTM coordinate of the zone 1. The following tool provides an online point choosing system: http://www.geoplaner.com/
We can find the zone 1 is (278369,3468927) in UTM format. So let’s handle the rest of data based on the initial point in Excel.
The function we want:
Simplify the code to just one line(it’s helpful for generating codes in Ecxel):
Change the output format in the JScoord (line 37):
Generate all x&y for codes in Excel:
Establish the HTML page for the coordinate table:
The result is a HTML table so that you can paste it into Excel sheet directly.
Let’s check the first point in Google Maps (It’s correct):
We get the coordinate of the Google version now. Also, you can transfer it into Baidu version too.
The final results on map:
- Heat Map
Visualization of the usage from public bike stations in Souzhou with a timeline.
Thanks for reading.
Please inform the errors to me from what you found.