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Display geographic coordinates (TWD97)?

I got an overview of Air Quality Monitoring Stations (as an attachment) from a government-owned data platform and read out the coordinates of TWD97 using Mathematica 11.2, but I was unable to come to an overview of the monitoring station GeoListPlot. Maybe Mathematica does not recognize the coordinates of TWD97. Are there any examples of geographic coordinate system conversions for reference?

In[4]:=a = Import["C:\\TLSA.json"];
b = a[[2, {8, 4}]];
In[5]:= b = a[[2, {8, 4}]];
In[6]:= GeoListPlot[b]
Out[6]= GeoListPlot[{"TWD97Lat" -> "22.9845810000",   "TWD97Lon" -> "120.2026170000"}]
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POSTED BY: Tsai Ming-Chou
3 Replies

The "TWD97" datum uses the same ellipsoid as the "WGS84" datum, which is effectively the same as the default "ITRF00" used in the WL. Your data already contains lat, lon numbers, so you can simply import the data and feed it to GeoPosition (ToExpression is needed to convert the strings to numbers):

positions = GeoPosition[Map[ToExpression, {"TWD97Lat", "TWD97Lon"} /. Import["~/Downloads/TLSA.json"], {2}]];

Then you can use it in any of the geo functions, like

GeoListPlot[positions]
GeoGraphics[{Red, Point[positions]}]

etc.

It's work! Helped me a great, thank you!

positions = GeoPosition[ Map[ToExpression, {"TWD97Lat", "TWD97Lon"} /. Import["~/Downloads/TLSA.json"][[All, {8, 4}]]]]; GeoListPlot[positions]

enter image description here

POSTED BY: Tsai Ming-Chou

Hi Tsai Ming-Chou,

unfortunately I can not give you an anwser to your question, but as a start you could consider the function GeodesyData. As far as I can see "TWD97" is not included explicitly, but maybe there is an equivalent datum.

Regards -- Henrik

POSTED BY: Henrik Schachner
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