Field calculator issue

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Field calculator issue

Carlos Cerdán
Hi list:

(Maybe related with Rob Vech e-mail: strange results when calculating area and perimeter )

I'm was trying calculate area of a layer with two polygons, but I can't get right values. Layer and project are in UTM 17s (epsg 32717) projection. I want square kilometers, so the used expression is:

$area/100000

Field type is real, 10 digits, 2 decimals (also tryed with 15 digits) buth result is wrong for one polygon and zero for second.

The layer has not geometric errors (I've check it), and can be download from https://sites.google.com/site/ccerdan/Home/Cuencas_Cajamarca.zip?attredirects=0&d=1

There are a field "Area_KM2" that was calculated in ArcGIS and it has the right values. The "Area_Ha" has the (wrong) result of QGIS field calculator.

What is wrong with field calculator?

UPDATE: After a reboot, field calculator found the right values... but What was wrong?

Carlos



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Re: Field calculator issue

Jonathan Moules-2
Hi Carlos,
There was this issue which has been fixed in Master apparently:


Jonathan


On 26 November 2013 13:13, Carlos Cerdán <[hidden email]> wrote:
Hi list:

(Maybe related with Rob Vech e-mail: strange results when calculating area and perimeter )

I'm was trying calculate area of a layer with two polygons, but I can't get right values. Layer and project are in UTM 17s (epsg 32717) projection. I want square kilometers, so the used expression is:

$area/100000

Field type is real, 10 digits, 2 decimals (also tryed with 15 digits) buth result is wrong for one polygon and zero for second.

The layer has not geometric errors (I've check it), and can be download from https://sites.google.com/site/ccerdan/Home/Cuencas_Cajamarca.zip?attredirects=0&d=1

There are a field "Area_KM2" that was calculated in ArcGIS and it has the right values. The "Area_Ha" has the (wrong) result of QGIS field calculator.

What is wrong with field calculator?

UPDATE: After a reboot, field calculator found the right values... but What was wrong?

Carlos



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Re: Field calculator issue

Carlos Cerdán
Thank you Jonathan. While 2.01 is the stable version, a reboot is an... ugly solution.

Regards

Carlos


2013/12/3 Jonathan Moules <[hidden email]>
Hi Carlos,
There was this issue which has been fixed in Master apparently:


Jonathan


On 26 November 2013 13:13, Carlos Cerdán <[hidden email]> wrote:
Hi list:

(Maybe related with Rob Vech e-mail: strange results when calculating area and perimeter )

I'm was trying calculate area of a layer with two polygons, but I can't get right values. Layer and project are in UTM 17s (epsg 32717) projection. I want square kilometers, so the used expression is:

$area/100000

Field type is real, 10 digits, 2 decimals (also tryed with 15 digits) buth result is wrong for one polygon and zero for second.

The layer has not geometric errors (I've check it), and can be download from https://sites.google.com/site/ccerdan/Home/Cuencas_Cajamarca.zip?attredirects=0&d=1

There are a field "Area_KM2" that was calculated in ArcGIS and it has the right values. The "Area_Ha" has the (wrong) result of QGIS field calculator.

What is wrong with field calculator?

UPDATE: After a reboot, field calculator found the right values... but What was wrong?

Carlos



_______________________________________________
Qgis-user mailing list
[hidden email]
http://lists.osgeo.org/mailman/listinfo/qgis-user


This transmission is intended for the named addressee(s) only and may contain sensitive or protectively marked material up to RESTRICTED and should be handled accordingly. Unless you are the named addressee (or authorised to receive it for the addressee) you may not copy or use it, or disclose it to anyone else. If you have received this transmission in error please notify the sender immediately. All email traffic sent to or from us, including without limitation all GCSX traffic, may be subject to recording and/or monitoring in accordance with relevant legislation.


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