Hi,
if(attribute(to_string( @NamelengthField )) != "LENGTH2", TRUE, FALSE )
("LENGHT2" is an existing field and @NamelengthField was a model input
string.)
This worked for me! If you have the time, please explain why I needed
the _attribute()_ function for this to work. I looked in the
documentation and did not find it very clear.
Thanks a million you saved my butt!
Nicolas
On 2021-07-20 5:53 a.m., Charles Dixon-Paver wrote:
Hi Nicholas,
I haven't had time to dig into this extensively or encountered this
particular issue, but I would suggest trying to "force" the expression
to retrieve the correct info regardless of context using something
like this:
with_variable('Length2', to_string(@NamelengthField) || '2',
if(attribute(to_string(@NamelengthField)) != attribute(@Length2),
TRUE, FALSE))
That's probably an extreme example but hopefully it illustrates my
point. If you want to share a sample dataset/ model I can try to have
a look at how to resolve it.
Regards
On Tue, 20 Jul 2021 at 10:46, Richard McDonnell
<[email protected] <mailto:[email protected]>> wrote:
Nicolas,
I have not looked at this in too much detail, but at a quick
glance, could it not be the fact that you should be using the
newly created fields? As in instead of *@NamelengthField !=
@NamelengthField || '2'*, should it not be more like your previous
example *Length != Length2*
Regards,
Richard
——
Richard McDonnell MSc GIS, FME Certified Professional
/FRM Data Management/
——
Oifig na nOibreacha Poiblí
Office of Public Works
Sráid Jonathan Swift, Baile Átha Troim, Co na Mí, C15 NX36
Jonathan Swift Street, Trim, Co Meath, C15 NX36
——
M +353 87 688 5964 T +353 46 942 2409
https://gov.ie/opw <https://gov.ie/opw>
——
To send me files larger than 30MB, please use the link below
https://filetransfer.opw.ie/filedrop/[email protected]
<https://filetransfer.opw.ie/filedrop/[email protected]>
Email Disclaimer:
https://www.gov.ie/en/organisation-information/439daf-email-disclaimer/
<https://www.gov.ie/en/organisation-information/439daf-email-disclaimer/>
*From:*Qgis-user <[email protected]
<mailto:[email protected]>> *On Behalf Of *Nicolas
Cadieux
*Sent:* 20 July 2021 09:27
*To:* Qgis Users List <[email protected]
<mailto:[email protected]>>
*Subject:* Re: [Qgis-user] Problem using Model Inputs variable in
an Select by expression in the model Designer
Hi,
Does anyone have an idea?
Nicolas Cadieux
https://gitlab.com/njacadieux <https://gitlab.com/njacadieux>
Le 8 juill. 2021 à 01:17, Nicolas Cadieux
<[email protected]
<mailto:[email protected]>> a écrit :
Hi,
I am creating a model that fixes Network files before they are
used in the QGIS Network analysis (Shortest path) tools.
This is my work flow:
1. Create a "Length" field (value) and calculate $length in
the field calculator
2. Split the Multipart lines into Singlepart lines
3. Create a "Length*2*" field (value) and calculate $length
in the field calculator
4. Select by expression Length != Length2. This basically
gives me a selection of line that have been modified by
the Multipart to Singlepart algorithm. (I get 8 results)
This works well
The problem is when I create and Input String to let the user
create a "Length" field. This become a variable called
@NamelengthField. My work flow become:
1. User input "Length" in the Model input. (@NamelengthField)
2. Create a "Length" field using @NamelengthField (as
pre-calculated value) and calculate $length in the field
calculator: This is OK
3. Split the Multipart lines into Singlepart lines: This is OK
4. Create a "Length2" field using @NamelengthField ||'2' (as
pre-calculated value) and calculate $length in the field
calculator: This is OK this field (Length2) is created and
calculated properly.
5. I get stuck when I try Select by expression using
@NamelengthField != @NamelengthField || '2' (as
pre-calculated value) (I get all lines back) and the test
does not work.
I tried stuff like
@NamelengthField != (@NamelengthField || '2')
'@NamelengthField != @NamelengthField || '2''
"@NamelengthField != @NamelengthField || '2'"
"@NamelengthField"|| !=|| "@NamelengthField || '2'"
Even simple @NamelengthField = 5.286365157529550 (which should
extract exactly one value).
Any ideas?
Nicolas
QGIS 3.18.2 on Windows 10
--
Nicolas Cadieux
https://gitlab.com/njacadieux <https://gitlab.com/njacadieux>
_______________________________________________
Qgis-user mailing list
[email protected] <mailto:[email protected]>
List info: https://lists.osgeo.org/mailman/listinfo/qgis-user
<https://lists.osgeo.org/mailman/listinfo/qgis-user>
Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
<https://lists.osgeo.org/mailman/listinfo/qgis-user>
--
Nicolas Cadieux
https://gitlab.com/njacadieux
_______________________________________________
Qgis-user mailing list
[email protected]
List info: https://lists.osgeo.org/mailman/listinfo/qgis-user
Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
