Different results using $length (field calculator) in QGIS versions 2.18 and 3.0
I use the fieldcalculator to measure the length of LineStrings in my shapefile layer, but i get different results when using QGIS 2.18 or QGIS 3.0.
If I am using the local coordinate system the difference between the QGIS 2.18 and QGIS 3.0 is not significant. If I am using WGS84 (I know you should always use the local coordinate system) I get two different results based on the version I am using. In 10 km the difference is almost 2 km..
Does anyone know what might be the reason? Did the algorithm behind the length calculations change in QGIS 3?
Thank you very much for your help!
gis qgis
asked Nov 15 '18 at 11:51
xathrinxathrin
112
add a comment |
I use the fieldcalculator to measure the length of LineStrings in my shapefile layer, but i get different results when using QGIS 2.18 or QGIS 3.0.
If I am using the local coordinate system the difference between the QGIS 2.18 and QGIS 3.0 is not significant. If I am using WGS84 (I know you should always use the local coordinate system) I get two different results based on the version I am using. In 10 km the difference is almost 2 km..
Does anyone know what might be the reason? Did the algorithm behind the length calculations change in QGIS 3?
Thank you very much for your help!
gis qgis
asked Nov 15 '18 at 11:51
xathrinxathrin
112
add a comment |
I use the fieldcalculator to measure the length of LineStrings in my shapefile layer, but i get different results when using QGIS 2.18 or QGIS 3.0.
If I am using the local coordinate system the difference between the QGIS 2.18 and QGIS 3.0 is not significant. If I am using WGS84 (I know you should always use the local coordinate system) I get two different results based on the version I am using. In 10 km the difference is almost 2 km..
Does anyone know what might be the reason? Did the algorithm behind the length calculations change in QGIS 3?
Thank you very much for your help!
gis qgis
asked Nov 15 '18 at 11:51
xathrinxathrin
112
I use the fieldcalculator to measure the length of LineStrings in my shapefile layer, but i get different results when using QGIS 2.18 or QGIS 3.0.
If I am using the local coordinate system the difference between the QGIS 2.18 and QGIS 3.0 is not significant. If I am using WGS84 (I know you should always use the local coordinate system) I get two different results based on the version I am using. In 10 km the difference is almost 2 km..
Does anyone know what might be the reason? Did the algorithm behind the length calculations change in QGIS 3?
Thank you very much for your help!
gis qgis
gis qgis
asked Nov 15 '18 at 11:51
xathrinxathrin
112
asked Nov 15 '18 at 11:51
xathrinxathrin
112
asked Nov 15 '18 at 11:51
xathrinxathrin
112
asked Nov 15 '18 at 11:51
xathrinxathrin
112
asked Nov 15 '18 at 11:51
xathrinxathrin
112
112
add a comment |
add a comment |
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