Re: Plot a map of Europe

[Christian T. Steigies]

On Tue, Nov 10, 2015 at 08:22:48PM +0100, Jorgen Sandberg wrote:
> 
> Thank you for your reply. The reason for my vague question is that I am 
> starting from scratch on plotting maps in Octave. I have searched the 
> internet, and the best I came across was M_Map and a reference to get the 
> coastline data from a NOAA website.
> 
> Ideally, I want to plot the coastlines of any selected part of the Earth and 
> the borders between the countries in a suitable projection such as Mercator 
> and hopefully others. On top of the map I want to plot the ground traces of 
> satellites.
> 
> Francesco gave me the solution to the last part except that it is not clear 
> to me how to ensure the map and the traces use the same projection. However, 
> I also need to know how to plot the coastlines and borders. Where do I find a 
> dataset defining the coastlines and borderlines that I can plot conveniently 
> in Octave? So, I need to go further back to the fundamentals than the reply 
> of Francesco. His "mapfile" I need to know where I can get one and how to 
> select the part of the world I am interested in and also the map projection.
> 
> Yes, it is really basic stuff, sorry.
> 
> M_Map has a lot of features for plotting maps, but there are 
> incompatibilities with Octave, unfortunately. The 'verLessThan' function I 
> have figured out to be a function determining whether the installed version 
> of Matlab is less than a specified version. The easiest is to throw it out 
> and ensure Octave compatible functions are called and not Matlab specific 
> functions.
> 
> However, my hope was that there is an easy and ready package for Octave 
> having the functionality I need. I can't find it and was hoping someone would 
> know a package and would give me a reference to it.
> 
> I have also contacted Rich Pawlowicz, who is the man behind the M_Map. He 
> replied to me that he had shown no interest in Octave since 2011 and hence 
> does not know about incompatibilities with Octave version 4.0.0.
> 
> Any help and advice is most welcome.

Does it have to be Octave? This sounds like a job for GMT:

http://gmt.soest.hawaii.edu/

It takes a bit to get used to, but once you get the hang of it, it produces
excellent maps. It even mentions an octave API (never tried this):

http://gmt.soest.hawaii.edu/projects/gmt-matlab-octave-api

Best you start with some examples:

http://gmt.soest.hawaii.edu/doc/5.1.0/gallery/ex31.html

Or you search a bit for an example with borders (and find a nice
description also):

http://geospatialdesktop.com/2008/02/desktop_gis_gmt_alaska_map/

Christian