[Qgis-user] spatialjoin
Randal Hale
rjhale at northrivergeographic.com
Thu Dec 22 05:36:40 PST 2016
Congrats - sorry I was almost leading own a more labor intensive path.
So now I have a question? I'm on QGIS 2.18 on Linux - Where is
geomintersects()? I don't see it in Field calculator as something I can
use (I have a lot of geom functions) but just not that currently. I was
reading back through all the emails and maybe I'm missing something (I
haven't tried my windows version yet).
Thanks in Advance,
Randy
On 12/22/2016 03:26 AM, Laurent Bourlet wrote:
>
> Hi at all
>
> i succeed !! thank's at all ...Andrew was right ... but i add an
> another thing ; i have indicated in the dialogue box , under "default
> value" , in "relational value" the name of the layer B , the right
> field etc... and now it's ok !
>
> one more time , thank's !!
>
> laurent
>
>
> Le 21/12/2016 à 23:32, Andrew a écrit :
>> Regarding the default values option/limitations, I can add that if
>> you try to use the default values expression dialog to build an
>> expression using geomintersects() the dialog will evaluate the
>> expression as invalid. Instead, build the expression in the field
>> calculator and then copy/paste it into default value box and skip
>> using the expression dialog.
>>
>> Andrew
>>
>> On Wed, Dec 21, 2016 at 1:32 PM, DelazJ <delazj at gmail.com
>> <mailto:delazj at gmail.com>> wrote:
>>
>> Hi,
>> Laurent, I can think about different ways you can test to tackle
>> your issues, provided you have two spatial layers that overlap
>> (and without any intermediate layer creation):
>> - recent QGIS introduce default values concept
>> (http://docs.qgis.org/testing/en/docs/user_manual/working_with_vector/vector_properties.html#common-settings
>> <http://docs.qgis.org/testing/en/docs/user_manual/working_with_vector/vector_properties.html#common-settings>)
>> - i'm not really sure about its limitations though
>> - add a virtual field
>> (http://docs.qgis.org/2.14/en/docs/user_manual/working_with_vector/attribute_table.html#editing-attribute-values
>> <http://docs.qgis.org/2.14/en/docs/user_manual/working_with_vector/attribute_table.html#editing-attribute-values>)
>> that you could later recalculate into a simple field
>> - use the Autofields plugin
>> (http://plugins.qgis.org/plugins/AutoFields/
>> <http://plugins.qgis.org/plugins/AutoFields/>)
>> - use the SpatialJoin plugin
>> (http://plugins.qgis.org/plugins/spatialJoin/
>> <http://plugins.qgis.org/plugins/spatialJoin/>)
>>
>> Except the SpatialJoin plugin option (which is internally based
>> on it), you'll need to write an expression likely based on
>> refFunctions plugin (e.g, geomintersects) someone mentioned above.
>>
>> HTH,
>> Harrissou
>>
>>
>> 2016-12-21 19:23 GMT+01:00 Laurent Bourlet
>> <laurentbourlet34 at gmail.com <mailto:laurentbourlet34 at gmail.com>>:
>>
>> Hi,
>>
>> i thought it was more easy ...
>>
>> In fact , i don't use a GPS because these points don't need
>> precision : they are only used to identify the parcels . And
>> i would like to catch their identity ( a number for each
>> parcel and the owner ) if possible with a dynamic spatialjoin...
>>
>> With booth data ( number of parcel and name of owner ) , i
>> could talk with the fisc administration :-)
>>
>> Randy was right ...i didn't have the same EPSG for the two
>> layers . It's now OK ! but without the feature "dynamic" .
>>
>> Indeed , i would avoid building many temporaries layers and i
>> thought it existed a plugin for this " dynamic" feature.
>>
>> If no , i will ask my users to make spatialjoins some time to
>> time ...
>>
>> Waiting , i will try the solution of Bernd...
>>
>> Thank you anyway !
>>
>> laurent
>>
>>
>>
>> Le 21/12/2016 à 17:46, Bernd Vogelgesang a écrit :
>>
>> Hi,
>>
>> for me this sounds more like he is getting new points
>> once in a while and
>> wants to join those attributes to the new points
>> "automatically" from the
>> parcel layer.
>>
>> The biggest problem for users is to rethink the workflow
>> from the end to
>> the beginning and to know the limitations.
>>
>> The outcome should be a point layer with the polygons
>> attributes. If those
>> points (layer A) are from GPS as Randy assumes, they have
>> to be
>> reprojected to the parcels layer (layer B) before being
>> able to join them
>> spatially(layer C). The spatial join in the toolbox
>> produces layer D.
>>
>> Most probably, the resulting layer D is going to to be
>> edited in some way
>> (adding notes about size, the progress, classifications,
>> whatever), so you
>> will have to find a way to preserve those new attribute
>> while being able to
>> add new points without much trouble.
>>
>> The processing toolbox is a good way to do these steps,
>> though it produces
>> a lot of temporary files cluttering the project.
>>
>> A better way for all those repetitive tasks, is to use
>> the graphical
>> modeller, to create a workflow which only has to be
>> triggered once new
>> points come in, and the resulting file can be saved as
>> new a file e.g.
>> with the current date in the name, so you have kind of an
>> archive and do not
>> overwrite previous files (and destroy your work in case
>> something goes
>> wrong).
>>
>> So I can imagine a model with input layer A (new points
>> in WGS84 without attributes) and a parcel layer B (in
>> whatever projection).
>> reproject layer A and C will be created as an
>> intermediate step.
>>
>> Next input layer is the latest result layer D,
>> reprojected and with attributes.
>> Merge layer C and D -> E. Now delete all columns which
>> are from layer B (from the last spatial join.
>> Unfortunately, you can only delete one field at a time in
>> the modeller, so you'll will have to add the command
>> several times in a row to the model) -> Fn
>> Do the spatial join of Fn with B.
>>
>> The last result G will now hold all points with the
>> corresponding parcel info plus additional fields you
>> might have added to the points.
>> G will be the input D in the next run with fresh points.
>>
>> So, do not add new points to the already existing
>> collection of points in WGS84 (it is never save to edit
>> layers without backup), but just import them as a new
>> input set and then run the model with the parcel layer
>> and the last result layer.
>>
>> The modeller is not as intuitive as it should be, but it
>> can save you a lot of time once you managed to set up a
>> model.
>>
>> Maybe I was completely wrong analysing the problem, but
>> maybe someone else has the problem that fits to my
>> solution ;)
>> Cheers
>> Bernd
>>
>>
>>
>>
>>
>> Am 21.12.2016, 14:07 Uhr, schrieb Randal Hale
>> <rjhale at northrivergeographic.com
>> <mailto:rjhale at northrivergeographic.com>>:
>>
>> 2 things:
>>
>> 1. In QGIS there is a processing toolbox (I assume
>> you are one something as new as version 2.14.8). Open
>> it (it's at the top -> Processing -> Toolbox). You
>> can search for tools. Search for "join" and you
>> should see a "Join Attributes by location". This is a
>> spatial join.
>>
>> 2. THE MOST IMPORTANT THING. You mentioned you had
>> collected points with a GPS. Possibly these points
>> are in EPSG:4326. I'm going to guess that your parcel
>> layer isn't. If you right click your parcel layer (in
>> the layers panel) it will allow you to select
>> properties. On the General Tab you will see the
>> Coordinate Reference System mentioned and many times
>> it is something like EPSG:xxxx . A Spatial Join must
>> have the layers in the same coordinate system.
>>
>> If it is different - Right Click on your GPS points
>> and "Save as". When the "Save vector layer as...."
>> window comes up. Save it as a shapefile and MOST
>> IMPORTANTLY change the CRS to match your parcel
>> layer. Click on the small globe (that appears to be
>> wearing a hat) and in the filter type in the number
>> you see for your parcels. You can then select that
>> projection and Save your file. It should save. You
>> can then perform the "join by location".
>>
>> It should work. You are very close though so don't worry.
>>
>> Randy
>>
>>
>>
>> On 12/21/2016 01:24 AM, Erwan Conseil wrote:
>>
>> Hi
>> In my layer B , I have the name of the owner and
>> the number of the parcel : this number , a
>> polygon , have a WKT location . All this is in a
>> SHP . As I grab points in layer A directly in
>> Qgis (2.18) , I have also a SHP . And i need a
>> dynamic join because I have no desire to make the
>> spatial join each time...
>> Regards
>> Laurent
>>
>> Le 21 déc. 2016 à 01:30, Randal Hale
>> <rjhale at northrivergeographic.com
>> <mailto:rjhale at northrivergeographic.com>> a
>> écrit :
>>
>> In your layer B - Do the Names of the Owners
>> have a location (like a tax parcel) or are
>> they a spreadsheet (like Microsoft Excel)?
>>
>> Randy
>>
>>
>> On 12/20/2016 06:03 PM, Laurent Bourlet
>> wrote:
>> Hi at all
>>
>> I'm a beginner in Qgis and i would make a
>> dynamic spatialjoin.
>> In fact , i have created a vector layer (
>> for example A) and i grab points in it
>> when I'm outdoor ( these points are
>> buildings unknowned by the government and
>> so these building are not taxed ...) . I
>> have also a layer (B) with the name of
>> the owners of these lands .
>> You see what i would ?...
>> I would have these names transferred as
>> attribut from B to A .
>> For that , i think about a spatialjoin
>> with a dynamic feature . So i have
>> downloaded the two plugins "reffunction"
>> and "spatialjoin".
>> But i have certainly maked something
>> wrong because i don't succeed ...
>>
>> Is it the good method ?
>>
>> And If yes , and if exist a doc about
>> these plugins ...i'll take it :-))
>>
>> regards
>>
>> Laurent
>>
>> ( pour les francophones ...je repère et
>> saisis des points représentants des
>> batiments construits et visibles par
>> Google Map mais inconnus par le cadastre
>> et donc les impôts ...je voudrais donc
>> enrichir la couche de saisie par les
>> références des parcelles et les noms des
>> propriétaires par une jointure spatiale
>> dynamique ..à chaque point saisi ,
>> "monte" cette référence )
>>
>> _______________________________________________
>> Qgis-user mailing list
>> Qgis-user at lists.osgeo.org
>> <mailto:Qgis-user at lists.osgeo.org>
>> List info:
>> http://lists.osgeo.org/mailman/listinfo/qgis-user
>> <http://lists.osgeo.org/mailman/listinfo/qgis-user>
>> Unsubscribe:
>> http://lists.osgeo.org/mailman/listinfo/qgis-user
>> <http://lists.osgeo.org/mailman/listinfo/qgis-user>
>>
>> -- -----------------
>> Randal Hale
>> North River Geographic Systems, Inc
>> http://www.northrivergeographic.com
>> <http://www.northrivergeographic.com>
>> 423.653.3611 rjhale at northrivergeographic.com
>> <mailto:rjhale at northrivergeographic.com>
>> twitter:rjhale
>>
>> _______________________________________________
>> Qgis-user mailing list
>> Qgis-user at lists.osgeo.org
>> <mailto:Qgis-user at lists.osgeo.org>
>> List info:
>> http://lists.osgeo.org/mailman/listinfo/qgis-user
>> <http://lists.osgeo.org/mailman/listinfo/qgis-user>
>> Unsubscribe:
>> http://lists.osgeo.org/mailman/listinfo/qgis-user
>> <http://lists.osgeo.org/mailman/listinfo/qgis-user>
>>
>>
>>
>>
>>
>> _______________________________________________
>> Qgis-user mailing list
>> Qgis-user at lists.osgeo.org <mailto:Qgis-user at lists.osgeo.org>
>> List info: http://lists.osgeo.org/mailman/listinfo/qgis-user
>> <http://lists.osgeo.org/mailman/listinfo/qgis-user>
>> Unsubscribe:
>> http://lists.osgeo.org/mailman/listinfo/qgis-user
>> <http://lists.osgeo.org/mailman/listinfo/qgis-user>
>>
>>
>>
>> _______________________________________________
>> Qgis-user mailing list
>> Qgis-user at lists.osgeo.org <mailto:Qgis-user at lists.osgeo.org>
>> List info: http://lists.osgeo.org/mailman/listinfo/qgis-user
>> <http://lists.osgeo.org/mailman/listinfo/qgis-user>
>> Unsubscribe: http://lists.osgeo.org/mailman/listinfo/qgis-user
>> <http://lists.osgeo.org/mailman/listinfo/qgis-user>
>>
>>
>>
>>
>> _______________________________________________
>> Qgis-user mailing list
>> Qgis-user at lists.osgeo.org
>> List info:http://lists.osgeo.org/mailman/listinfo/qgis-user
>> Unsubscribe:http://lists.osgeo.org/mailman/listinfo/qgis-user
>
>
>
> _______________________________________________
> Qgis-user mailing list
> Qgis-user at lists.osgeo.org
> List info: http://lists.osgeo.org/mailman/listinfo/qgis-user
> Unsubscribe: http://lists.osgeo.org/mailman/listinfo/qgis-user
--
-----------------
Randal Hale
North River Geographic Systems, Inc
http://www.northrivergeographic.com
423.653.3611 rjhale at northrivergeographic.com
twitter:rjhale
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/qgis-user/attachments/20161222/666c2920/attachment.html>
More information about the Qgis-user
mailing list