Sv: Re: [Qgis-user] Creating polygon from points in csv file

[Goyo]

Hello Ulf,

El sáb, 22-05-2010 a las 00:01 +0200, Ulf Almroth escribió:
> Hi,
> 
> Using an attribute is agood idea. A lot of measuring devices 
> generating ascii files with coordinates, e.g. various type of surveying 
> equipment and coordinate measuring devices 
> for industrial use produces file that basically look like this:
> 
> featuretyp, X,Y,Z,pencode
> 
> A sample file from a steroplotter used for mapping arial images with 
> sterooverlpa looks like this:
> 
> BBH  1868462.502  7323256.557  5.266  21
> BBH  1868458.596  7323265.540  5.266  22
> BBH  1868452.062  7323262.698  5.266  22
> BBH  1868455.967  7323253.716  5.266  22
> BBH  1868462.502  7323256.557  5.266  23
> BBH  1868359.027  7322916.789  6.259  21
> BBH  1868357.951  7322925.557  6.259  22
> BBH  1868351.513  7322924.767  6.259  22
> BBH  1868352.589  7322915.999  6.259  22
> BBH  1868359.027  7322916.789  6.259  23
> 
> where   21  signifies the styart of the polygon (or line) and 23 the 
> end.

Since the points are sorted you can just group by the Z field. Then you
get two polygons in this example without the need to look at the
pencode. Or maybe it's not as simple as I think?

I don't want to clutter the interface with more options without an use
case which makes them necessary.

Goyo

> 
> Regards 
> 
> Ulf Almroth
> 
> 
> ----Ursprungligt meddelande----
> Från: goyodiaz at gmail.com
> Datum: 2010-05-20 00:03
> Till: "MORREALE Jean Roc"<jr.morreale at enoreth.net>
> Kopia: "qgis-user List"<qgis-user at lists.osgeo.org>
> Ärende: Re: [Qgis-user] Creating polygon from points in csv file
> 
> El mié, 19-05-2010 a las 22:20 +0200, MORREALE Jean Roc escribió:
> > Hi Goyo,
> > 
> > I would like to test your file but I can't not extract the file from 
> the 
> > tar.bin, could you resend it using a more common format ?
> 
> The original author, Pavol Kapusta, uploaded (a new version of) it to
> the contributed repository so you should be able to install it using 
> the
> plugin installer (plugins > Install python plugins).
> 
> Please send bug reports and suggestion here or to me.
> 
> > 
> > Your modification is great as it would solve a major pain I've been 
> > dealing with my tacheometer's output, it is a basic ascii file where 
> > every record is a point to which you can append a codification.
> > 
> > For now we've to connect the point by hand, automating this task 
> would 
> > be a relief (and a lot less error prone).
> > 
> > Would it be easier to make a correct geometry by assigning a code to 
> the 
> > point telling if it's the opening or the closure ? Or just following 
> the 
> > incrementing point number would be enough to get a correct geometry ?
> 
> As for now the plugin assumes the points are in the proper order.
> Sorting them by an attribute sounds like a good idea to me, I'?l think
> about it.
> 
> Goyo
> 
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