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Mercator projection from http://mathworld.wolfram.com/MercatorProjection.html with missing earth.pts

• To: mathgroup at smc.vnet.net
• Subject: [mg53250] Mercator projection from http://mathworld.wolfram.com/MercatorProjection.html with missing earth.pts
• From: Klamser at t-online.de (klamser)
• Date: Mon, 3 Jan 2005 04:29:27 -0500 (EST)
• References: <cqtc4e$7ic$1@smc.vnet.net> <200412300638.BAA23335@smc.vnet.net> <cr33o5$jcn$1@smc.vnet.net> <200501010733.CAA01157@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

Hello,

under

http://mathworld.wolfram.com/MercatorProjection.html

everyone can get a notebook about the Mercator projection.

In this NB you can find the statement:

For a list of Eric's math packages that may be needed to evaluate this 
notebook, see http://mathworld.wolfram.com/packages/.  An archive of 
these packages may be downloaded from 
http://mathworld.wolfram.com/packages/MathWorldPackages.zip, as well as 
from the Mathematica Information Center's MathSource item 4775.  A list 
of Eric's utility packages that may be needed to evaluate this notebook 
may be downloaded from MathSource item 5087.

No problem downloading and installing 
http://mathworld.wolfram.com/packages/MathWorldPackages.zip.

But it needs the file: earth.pts

But I don't know where I can find it. Internet search with google does 
not help.

No problem, I thought, because Mathematica obtains the 
<<Miscellaneous`WorldData` package.

With

Needs["Miscellaneous`WorldPlot`"]
wd = {#1, WorldData[#1]/60 // N} & /@ Map[ToString, World];
wd >> "c:\\z\\bin\\w.pts";

I can extract the Data an put it into a file, where 
MercatorProjection.nb can read it.

But it does not work.

The package << MathWorld`MapProjections` contains the code for reading 
the data:

MapCoordinates[opts___] := Module[
 {data, pos, dir = StringJoin[{MapDirectory,Directory} /. {opts} /.  
Options[MapCoordinates]], file = MapFile /. {opts} 
/.Options[MapCoordinates]},
(*=>*) data = ReadList[dir <> file, Word, RecordLists -> 
True,WordSeparators -> {"\t", " "}, RecordSeparators -> {"\n"}];
(*=>*) pos = Flatten[Position[First /@ data, _?(StringTake[#, 1] == "#" 
&)]];
(*=>*) ToExpression /@ Take[data, #] & /@ Transpose[{Most[pos + 1], 
Rest[pos - 1]}]Degree];

Can someone tell me,
a) where can I find a file earth.pts or
b) which format the earth.pts file must have, that the << 
MathWorld`MapProjections` package works fine.

Kind regards,

Peter Klamser

• References:
  • Re: Re: Matrix Operator form using Mathematica
    • From: "Steve Luttrell" <steve_usenet@_removemefirst_luttrell.org.uk>