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

2010-05-25 Thread Goyo
El mar, 25-05-2010 a las 20:59 +0200, Ulf Almroth escribió:
> [...]
> Think of polygons 
> representing landuse or cadstral divisons or lines representing streams 
> or roads. In this simple file structure a line looks like this:
> 
> STOLP  1868536.305  7323297.568  5.206  21
> STOLP  1868514.063  7323234.352  2.558  22
> STOLP  1868445.482  7323050.904  3.220  22
> STOLP  1868514.063  7323234.352  2.558  23
> 
> The polygon differs rom the line in that the points with pencode 21 &v 
> 23 have the same coordinates indicating the closure. Point have the 
> pencode 11 indicating no connection:
> 
> AHP,1868280.000,7323450.000,0.271,11
> AHP,1868300.000,7323450.000,1.324,11
> AHP,1868320.000,7323450.000,0.542,11

I think I understand now. This seems to imply that we have to create
point, line and polygon shapefiles from the same input file. I think
this is a bit beyond the initial scope of the plugin and will need some
rethinking. Anyway I'll try to work on it when I have some spare time.

I'm setting a launchpad project for points2one and filed this as a
feature request:

https://bugs.launchpad.net/points2one/+bug/585604

Goyo

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

2010-05-25 Thread Ulf Almroth
Hello Goyo,

I see I made a bad choice of sample file. The Z is the same in 
polygons because they represent small buildings. To create them the 
corners of the roofs were measured in the stereomodel resulting in the 
same z values. Of course a lot of objects have a common Z like lakes 
and shorelines and many others. The more general case is that Z i 
varying from ponint to point in the polygon or line. Think of polygons 
representing landuse or cadstral divisons or lines representing streams 
or roads. In this simple file structure a line looks like this:

STOLP  1868536.305  7323297.568  5.206  21
STOLP  1868514.063  7323234.352  2.558  22
STOLP  1868445.482  7323050.904  3.220  22
STOLP  1868514.063  7323234.352  2.558  23

The polygon differs rom the line in that the points with pencode 21 &v 
23 have the same coordinates indicating the closure. Point have the 
pencode 11 indicating no connection:

AHP,1868280.000,7323450.000,0.271,11
AHP,1868300.000,7323450.000,1.324,11
AHP,1868320.000,7323450.000,0.542,11

I tried to get those files into Qgis but with no complete succes. There 
is one plug in redings csv files ok but i does not take care of the 
topology and only reads X & Y.

Best regards

Ulf



Ursprungligt meddelande
Från: goyod...@gmail.com
Datum: 2010-05-24 22:35
Till: "Ulf Almroth"
Kopia: "MORREALE Jean Roc", "qgis-user List"

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

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: goyod...@gmail.com
> Datum: 2010-05-20 00:03
> Till: "MORREALE Jean Roc"
> Kopia: "qgis-user List"
> 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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> 
> 





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

2010-05-24 Thread 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: goyod...@gmail.com
> Datum: 2010-05-20 00:03
> Till: "MORREALE Jean Roc"
> Kopia: "qgis-user List"
> 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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> http://lists.osgeo.org/mailman/listinfo/qgis-user
> 
> 
> 


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

2010-05-21 Thread Ulf Almroth
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. 

Regards 

Ulf Almroth


Ursprungligt meddelande
Från: goyod...@gmail.com
Datum: 2010-05-20 00:03
Till: "MORREALE Jean Roc"
Kopia: "qgis-user List"
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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Re: [Qgis-user] Creating polygon from points in csv file

2010-05-19 Thread Goyo
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'ĺl think
about it.

Goyo

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

2010-05-19 Thread MORREALE Jean Roc

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 ?


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 ?


Regards,
MORREALE Jean Roc

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

2010-05-14 Thread nikos ves
On Fri, 2010-05-14 at 14:48 -0500, mir wrote:
> Perfect, Points2One worked straight away!  Thank you all very much.
> 
> mir
> 


Glad my suggestion helped you, but the real credit goes to the author,
and in his/her wonderful plugin!

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

2010-05-14 Thread mir
Perfect, Points2One worked straight away!  Thank you all very much.

mir

On 12 May 2010 12:49, nikos ves  wrote:
> On Wed, 2010-05-12 at 12:11 -0500, mir wrote:
>> Hello all,
>>
>> I have a list of points in sequence that define a polygon.  This is
>> taken from a legal document defining a piece of land.  So far I have
>> been able to import this into Qgis as points.  How do I import it as a
>> polygon (or convert the points to a polygon?  I have tried to use
>> GRASS, importing it as an ASCII file, but I guess I never got the
>> ASCII polygon format down.
>>
>> I'm sure there must be an asy way.  Help!
>>
>> mir
>>
>
> You can use the "Points2One" plugin which makes the task you need.
> As input takes a point layer and as output gives a polygon or a
> polyline. In your case you can choose polygon.
>
> Be careful with the order of the points, otherwise you might get funny
> results.
>
> eg      |1 2|  is fine , but
>        |4 3|
>
>        |1 2| will intersect with itself, making two triangles!
>        |3 4|
>
>
> Ves Nikos
>
>



-- 
_
Mir Rodríguez Lombardo
Fundación Almanaque Azul
Calle 4a San Felipe, antigua Santa Familia
Ciudad de Panamá
tel +507 836 6452
cel 6644 9214
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Re: [Qgis-user] Creating polygon from points in csv file

2010-05-12 Thread Goyo
Sorry I send a very buggy version, try this one instead.

Goyo

El jue, 13-05-2010 a las 01:51 +0200, Goyo escribió:
> El mié, 12-05-2010 a las 21:02 +0300, nikos ves escribió:
> > One problem I see, is multiple polygones merged in One big messy
> > polygone due to hte fact that it cant "understand" where a polygon ends
> > and the next one starts.
> 
> I've been working in a modified version of Points2One which allows
> creation of several polygons or polylines grouping vertices by a given
> attribute. I still don't consider it release ready but the attached
> version works for me.
> 
> Goyo



points2one.tar.gz
Description: application/compressed-tar
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Re: [Qgis-user] Creating polygon from points in csv file

2010-05-12 Thread Goyo
El mié, 12-05-2010 a las 21:02 +0300, nikos ves escribió:
> One problem I see, is multiple polygones merged in One big messy
> polygone due to hte fact that it cant "understand" where a polygon ends
> and the next one starts.

I've been working in a modified version of Points2One which allows
creation of several polygons or polylines grouping vertices by a given
attribute. I still don't consider it release ready but the attached
version works for me.

Goyo


points2one.tar.gz
Description: application/compressed-tar
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Re: [Qgis-user] Creating polygon from points in csv file

2010-05-12 Thread nikos ves
On Wed, 2010-05-12 at 13:44 -0500, Gerald Creager wrote:
> Nikos, will Points2One work for lines, as well, or just for polygons? I 
> have a similar issue: I need to create polylines from a CSV file... I, 
> too, can digitize the points into lines, but, why?
> 
> Thanks Gerry
> 

Just test it, It successfully made a line across all the points, except
for the inconvenience that is making just ONE line.

Unfortunately, as I've found, QGIS lacks vertex-level editing (delete
multiple vertices in line/polygon; move multiple vertices) at least in
v1.1 which seems to be the case in 1.5. 
 


 
> nikos ves wrote:
> > On Wed, 2010-05-12 at 13:51 -0400, M S wrote:
> >> I guess the practically of this suggestion depends on how many points.
> >>  How about digitizing and snapping the new polygon to the points?
> >>
> >> Mark
> >>
> > This would also work, but the why bother, since already has the points
> > in a csv file?
> > 
> > One problem I see, is multiple polygones merged in One big messy
> > polygone due to hte fact that it cant "understand" where a polygon ends
> > and the next one starts. If that case arise  a little editing comes
> > handy.
> > 
> > The whole point as I see it is to minimize doing double work
> >  
> >  
> > Ofcouse if the plugin is inadequate for the job, the next option is to
> > shape the polygons from, as Mark said, the points mir already has
> > utilizing the snap feature
> > 
> > 
> > 
> >> On Wed, May 12, 2010 at 1:11 PM, mir  wrote:
> >>> Hello all,
> >>>
> >>> I have a list of points in sequence that define a polygon.  This is
> >>> taken from a legal document defining a piece of land.  So far I have
> >>> been able to import this into Qgis as points.  How do I import it as a
> >>> polygon (or convert the points to a polygon?  I have tried to use
> >>> GRASS, importing it as an ASCII file, but I guess I never got the
> >>> ASCII polygon format down.
> >>>
> >>> I'm sure there must be an asy way.  Help!
> >>>
> >>> mir
> >>>
> >>> --
> >>> _
> >>> Mir Rodríguez Lombardo
> >>> Fundación Almanaque Azul
> >>> Calle 4a San Felipe, antigua Santa Familia
> >>> Ciudad de Panamá
> >>> tel +507 836 6452
> >>> cel 6644 9214
> >>> ___
> >>> Qgis-user mailing list
> >>> Qgis-user@lists.osgeo.org
> >>> http://lists.osgeo.org/mailman/listinfo/qgis-user
> >>>
> >> ___
> >> Qgis-user mailing list
> >> Qgis-user@lists.osgeo.org
> >> http://lists.osgeo.org/mailman/listinfo/qgis-user
> > 
> > 
> > ___
> > Qgis-user mailing list
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> > http://lists.osgeo.org/mailman/listinfo/qgis-user
> 


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

2010-05-12 Thread Gerald Creager
Nikos, will Points2One work for lines, as well, or just for polygons? I 
have a similar issue: I need to create polylines from a CSV file... I, 
too, can digitize the points into lines, but, why?


Thanks Gerry

nikos ves wrote:

On Wed, 2010-05-12 at 13:51 -0400, M S wrote:

I guess the practically of this suggestion depends on how many points.
 How about digitizing and snapping the new polygon to the points?

Mark


This would also work, but the why bother, since already has the points
in a csv file?

One problem I see, is multiple polygones merged in One big messy
polygone due to hte fact that it cant "understand" where a polygon ends
and the next one starts. If that case arise  a little editing comes
handy.

The whole point as I see it is to minimize doing double work
 
 
Ofcouse if the plugin is inadequate for the job, the next option is to

shape the polygons from, as Mark said, the points mir already has
utilizing the snap feature




On Wed, May 12, 2010 at 1:11 PM, mir  wrote:

Hello all,

I have a list of points in sequence that define a polygon.  This is
taken from a legal document defining a piece of land.  So far I have
been able to import this into Qgis as points.  How do I import it as a
polygon (or convert the points to a polygon?  I have tried to use
GRASS, importing it as an ASCII file, but I guess I never got the
ASCII polygon format down.

I'm sure there must be an asy way.  Help!

mir

--
_
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Fundación Almanaque Azul
Calle 4a San Felipe, antigua Santa Familia
Ciudad de Panamá
tel +507 836 6452
cel 6644 9214
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--
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Texas Mesonet -- AATLT, Texas A&M University
Cell: 979.229.5301 Office: 979.458.4020 FAX: 979.862.3983
Office: 1700 Research Parkway Ste 160, TAMU, College Station, TX 77843
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Re: [Qgis-user] Creating polygon from points in csv file

2010-05-12 Thread nikos ves
On Wed, 2010-05-12 at 13:51 -0400, M S wrote:
> I guess the practically of this suggestion depends on how many points.
>  How about digitizing and snapping the new polygon to the points?
> 
> Mark
> 
This would also work, but the why bother, since already has the points
in a csv file?

One problem I see, is multiple polygones merged in One big messy
polygone due to hte fact that it cant "understand" where a polygon ends
and the next one starts. If that case arise  a little editing comes
handy.

The whole point as I see it is to minimize doing double work
 
 
Ofcouse if the plugin is inadequate for the job, the next option is to
shape the polygons from, as Mark said, the points mir already has
utilizing the snap feature



> On Wed, May 12, 2010 at 1:11 PM, mir  wrote:
> > Hello all,
> >
> > I have a list of points in sequence that define a polygon.  This is
> > taken from a legal document defining a piece of land.  So far I have
> > been able to import this into Qgis as points.  How do I import it as a
> > polygon (or convert the points to a polygon?  I have tried to use
> > GRASS, importing it as an ASCII file, but I guess I never got the
> > ASCII polygon format down.
> >
> > I'm sure there must be an asy way.  Help!
> >
> > mir
> >
> > --
> > _
> > Mir Rodríguez Lombardo
> > Fundación Almanaque Azul
> > Calle 4a San Felipe, antigua Santa Familia
> > Ciudad de Panamá
> > tel +507 836 6452
> > cel 6644 9214
> > ___
> > Qgis-user mailing list
> > Qgis-user@lists.osgeo.org
> > http://lists.osgeo.org/mailman/listinfo/qgis-user
> >
> ___
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> http://lists.osgeo.org/mailman/listinfo/qgis-user


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

2010-05-12 Thread M S
I guess the practically of this suggestion depends on how many points.
 How about digitizing and snapping the new polygon to the points?

Mark

On Wed, May 12, 2010 at 1:11 PM, mir  wrote:
> Hello all,
>
> I have a list of points in sequence that define a polygon.  This is
> taken from a legal document defining a piece of land.  So far I have
> been able to import this into Qgis as points.  How do I import it as a
> polygon (or convert the points to a polygon?  I have tried to use
> GRASS, importing it as an ASCII file, but I guess I never got the
> ASCII polygon format down.
>
> I'm sure there must be an asy way.  Help!
>
> mir
>
> --
> _
> Mir Rodríguez Lombardo
> Fundación Almanaque Azul
> Calle 4a San Felipe, antigua Santa Familia
> Ciudad de Panamá
> tel +507 836 6452
> cel 6644 9214
> ___
> Qgis-user mailing list
> Qgis-user@lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/qgis-user
>
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Re: [Qgis-user] Creating polygon from points in csv file

2010-05-12 Thread nikos ves
On Wed, 2010-05-12 at 12:11 -0500, mir wrote:
> Hello all,
> 
> I have a list of points in sequence that define a polygon.  This is
> taken from a legal document defining a piece of land.  So far I have
> been able to import this into Qgis as points.  How do I import it as a
> polygon (or convert the points to a polygon?  I have tried to use
> GRASS, importing it as an ASCII file, but I guess I never got the
> ASCII polygon format down.
> 
> I'm sure there must be an asy way.  Help!
> 
> mir
> 

You can use the "Points2One" plugin which makes the task you need.
As input takes a point layer and as output gives a polygon or a
polyline. In your case you can choose polygon.

Be careful with the order of the points, otherwise you might get funny
results. 

eg  |1 2|  is fine , but
|4 3|

|1 2| will intersect with itself, making two triangles!  
|3 4|


Ves Nikos

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

2010-05-12 Thread mir
Hello all,

I have a list of points in sequence that define a polygon.  This is
taken from a legal document defining a piece of land.  So far I have
been able to import this into Qgis as points.  How do I import it as a
polygon (or convert the points to a polygon?  I have tried to use
GRASS, importing it as an ASCII file, but I guess I never got the
ASCII polygon format down.

I'm sure there must be an asy way.  Help!

mir

-- 
_
Mir Rodríguez Lombardo
Fundación Almanaque Azul
Calle 4a San Felipe, antigua Santa Familia
Ciudad de Panamá
tel +507 836 6452
cel 6644 9214
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