Mixing
Using QGIS to remove portions of polygons that overlap in same layer?
Is there a way to easily eliminate the overlapping portions of polygons in the same layer?
For example, I want to turn this
into this
I used Union to break the polygons apart where they overlapped, and then used Delete Duplicate Geometries to get rid of half the overlaps, but still had to manually delete the others. That's fine for the example, but won't work with the large amount of polygons that will be in the real data.
qgis overlapping-features
edited Jan 29 at 23:15
PolyGeo♦
53.7k1781244
asked Jan 25 at 20:42
ChadChad
283
add a comment |
Is there a way to easily eliminate the overlapping portions of polygons in the same layer?
For example, I want to turn this
into this
I used Union to break the polygons apart where they overlapped, and then used Delete Duplicate Geometries to get rid of half the overlaps, but still had to manually delete the others. That's fine for the example, but won't work with the large amount of polygons that will be in the real data.
qgis overlapping-features
edited Jan 29 at 23:15
PolyGeo♦
53.7k1781244
asked Jan 25 at 20:42
ChadChad
283
1
Thank you for including "before" and "after" images of what you're trying to achieve. It made your question easy to understand.
– csk
Jan 25 at 20:58
add a comment |
Is there a way to easily eliminate the overlapping portions of polygons in the same layer?
For example, I want to turn this
into this
I used Union to break the polygons apart where they overlapped, and then used Delete Duplicate Geometries to get rid of half the overlaps, but still had to manually delete the others. That's fine for the example, but won't work with the large amount of polygons that will be in the real data.
qgis overlapping-features
edited Jan 29 at 23:15
PolyGeo♦
53.7k1781244
asked Jan 25 at 20:42
ChadChad
283
Is there a way to easily eliminate the overlapping portions of polygons in the same layer?
For example, I want to turn this
into this
I used Union to break the polygons apart where they overlapped, and then used Delete Duplicate Geometries to get rid of half the overlaps, but still had to manually delete the others. That's fine for the example, but won't work with the large amount of polygons that will be in the real data.
qgis overlapping-features
qgis overlapping-features
edited Jan 29 at 23:15
PolyGeo♦
53.7k1781244
asked Jan 25 at 20:42
ChadChad
283
edited Jan 29 at 23:15
PolyGeo♦
53.7k1781244
asked Jan 25 at 20:42
ChadChad
283
edited Jan 29 at 23:15
PolyGeo♦
53.7k1781244
edited Jan 29 at 23:15
PolyGeo♦
53.7k1781244
edited Jan 29 at 23:15
PolyGeo♦
53.7k1781244
53.7k1781244
asked Jan 25 at 20:42
ChadChad
283
asked Jan 25 at 20:42
ChadChad
283
asked Jan 25 at 20:42
ChadChad
283
283
1
Thank you for including "before" and "after" images of what you're trying to achieve. It made your question easy to understand.
– csk
Jan 25 at 20:58
add a comment |
1
Thank you for including "before" and "after" images of what you're trying to achieve. It made your question easy to understand.
– csk
Jan 25 at 20:58
1
1
Thank you for including "before" and "after" images of what you're trying to achieve. It made your question easy to understand.
– csk
Jan 25 at 20:58
Thank you for including "before" and "after" images of what you're trying to achieve. It made your question easy to understand.
– csk
Jan 25 at 20:58
add a comment |
3 Answers
3
active
oldest
votes
QGIS Processing Toolbox has a SAGA Polygon self-intersection tool (under SAGA | Vector polygon tools).
It works much like QIGS Union Tool, while this tool retains only one feature per the overlapped area.
Open the attribute table of generated Intersection layer and select Delete all features whose fid (or id) is 0.
answered Jan 26 at 0:35
KazuhitoKazuhito
16.2k41884
add a comment |
Just to add another workaround with QGIS built-in functions:
Intersect the polygons layer against itself.
The output is an Intersection layer with all the geometries of the polygons layer and new geometries for their overlapped areas.
Select by location the geometries of the Intersection layer than are equal (parameter) to polygons layer geometries, and Delete them.
The output is, in the same Intersection layer, two or more geometries for any overlap in the polygons layer.
- Make the Difference between the polygons layer and the edited Intersection layer.
The output is a new Difference layer, with the geometries of the polygons layer without the overlapped areas.
answered Jan 26 at 2:24
Gabriel De LucaGabriel De Luca
3,1581220
add a comment |
Use the Symmetrical Difference tool.
Symmetrical difference
This algorithm extracts the portions of features from both the Input and Overlay layers that do not overlap. Overlapping areas between the two layers are removed. The attribute table of the Symmetrical Difference layer contains original attributes from both the Input and Difference layers.
answered Jan 25 at 20:55
cskcsk
9,1451035
Thanks for the help. But does this only work if they are in different layers? When I tried it, I got a blank layer. All the overlapping features will be in the same layer.
– Chad
Jan 25 at 22:39
add a comment |
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3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
QGIS Processing Toolbox has a SAGA Polygon self-intersection tool (under SAGA | Vector polygon tools).
It works much like QIGS Union Tool, while this tool retains only one feature per the overlapped area.
Open the attribute table of generated Intersection layer and select Delete all features whose fid (or id) is 0.
answered Jan 26 at 0:35
KazuhitoKazuhito
16.2k41884
add a comment |
QGIS Processing Toolbox has a SAGA Polygon self-intersection tool (under SAGA | Vector polygon tools).
It works much like QIGS Union Tool, while this tool retains only one feature per the overlapped area.
Open the attribute table of generated Intersection layer and select Delete all features whose fid (or id) is 0.
answered Jan 26 at 0:35
KazuhitoKazuhito
16.2k41884
add a comment |
QGIS Processing Toolbox has a SAGA Polygon self-intersection tool (under SAGA | Vector polygon tools).
It works much like QIGS Union Tool, while this tool retains only one feature per the overlapped area.
Open the attribute table of generated Intersection layer and select Delete all features whose fid (or id) is 0.
answered Jan 26 at 0:35
KazuhitoKazuhito
16.2k41884
QGIS Processing Toolbox has a SAGA Polygon self-intersection tool (under SAGA | Vector polygon tools).
It works much like QIGS Union Tool, while this tool retains only one feature per the overlapped area.
Open the attribute table of generated Intersection layer and select Delete all features whose fid (or id) is 0.
answered Jan 26 at 0:35
KazuhitoKazuhito
16.2k41884
edited Jan 26 at 1:27
answered Jan 26 at 0:35
KazuhitoKazuhito
16.2k41884
answered Jan 26 at 0:35
KazuhitoKazuhito
16.2k41884
answered Jan 26 at 0:35
KazuhitoKazuhito
16.2k41884
16.2k41884
add a comment |
add a comment |
Just to add another workaround with QGIS built-in functions:
Intersect the polygons layer against itself.
The output is an Intersection layer with all the geometries of the polygons layer and new geometries for their overlapped areas.
Select by location the geometries of the Intersection layer than are equal (parameter) to polygons layer geometries, and Delete them.
The output is, in the same Intersection layer, two or more geometries for any overlap in the polygons layer.
- Make the Difference between the polygons layer and the edited Intersection layer.
The output is a new Difference layer, with the geometries of the polygons layer without the overlapped areas.
answered Jan 26 at 2:24
Gabriel De LucaGabriel De Luca
3,1581220
add a comment |
Just to add another workaround with QGIS built-in functions:
Intersect the polygons layer against itself.
The output is an Intersection layer with all the geometries of the polygons layer and new geometries for their overlapped areas.
Select by location the geometries of the Intersection layer than are equal (parameter) to polygons layer geometries, and Delete them.
The output is, in the same Intersection layer, two or more geometries for any overlap in the polygons layer.
- Make the Difference between the polygons layer and the edited Intersection layer.
The output is a new Difference layer, with the geometries of the polygons layer without the overlapped areas.
answered Jan 26 at 2:24
Gabriel De LucaGabriel De Luca
3,1581220
add a comment |
Just to add another workaround with QGIS built-in functions:
Intersect the polygons layer against itself.
The output is an Intersection layer with all the geometries of the polygons layer and new geometries for their overlapped areas.
Select by location the geometries of the Intersection layer than are equal (parameter) to polygons layer geometries, and Delete them.
The output is, in the same Intersection layer, two or more geometries for any overlap in the polygons layer.
- Make the Difference between the polygons layer and the edited Intersection layer.
The output is a new Difference layer, with the geometries of the polygons layer without the overlapped areas.
answered Jan 26 at 2:24
Gabriel De LucaGabriel De Luca
3,1581220
Just to add another workaround with QGIS built-in functions:
Intersect the polygons layer against itself.
The output is an Intersection layer with all the geometries of the polygons layer and new geometries for their overlapped areas.
Select by location the geometries of the Intersection layer than are equal (parameter) to polygons layer geometries, and Delete them.
The output is, in the same Intersection layer, two or more geometries for any overlap in the polygons layer.
- Make the Difference between the polygons layer and the edited Intersection layer.
The output is a new Difference layer, with the geometries of the polygons layer without the overlapped areas.
answered Jan 26 at 2:24
Gabriel De LucaGabriel De Luca
3,1581220
answered Jan 26 at 2:24
Gabriel De LucaGabriel De Luca
3,1581220
answered Jan 26 at 2:24
Gabriel De LucaGabriel De Luca
3,1581220
answered Jan 26 at 2:24
Gabriel De LucaGabriel De Luca
3,1581220
3,1581220
add a comment |
add a comment |
Use the Symmetrical Difference tool.
Symmetrical difference
This algorithm extracts the portions of features from both the Input and Overlay layers that do not overlap. Overlapping areas between the two layers are removed. The attribute table of the Symmetrical Difference layer contains original attributes from both the Input and Difference layers.
answered Jan 25 at 20:55
cskcsk
9,1451035
Thanks for the help. But does this only work if they are in different layers? When I tried it, I got a blank layer. All the overlapping features will be in the same layer.
– Chad
Jan 25 at 22:39
add a comment |
Use the Symmetrical Difference tool.
Symmetrical difference
This algorithm extracts the portions of features from both the Input and Overlay layers that do not overlap. Overlapping areas between the two layers are removed. The attribute table of the Symmetrical Difference layer contains original attributes from both the Input and Difference layers.
answered Jan 25 at 20:55
cskcsk
9,1451035
Thanks for the help. But does this only work if they are in different layers? When I tried it, I got a blank layer. All the overlapping features will be in the same layer.
– Chad
Jan 25 at 22:39
add a comment |
Use the Symmetrical Difference tool.
Symmetrical difference
This algorithm extracts the portions of features from both the Input and Overlay layers that do not overlap. Overlapping areas between the two layers are removed. The attribute table of the Symmetrical Difference layer contains original attributes from both the Input and Difference layers.
answered Jan 25 at 20:55
cskcsk
9,1451035
Use the Symmetrical Difference tool.
Symmetrical difference
This algorithm extracts the portions of features from both the Input and Overlay layers that do not overlap. Overlapping areas between the two layers are removed. The attribute table of the Symmetrical Difference layer contains original attributes from both the Input and Difference layers.
answered Jan 25 at 20:55
cskcsk
9,1451035
answered Jan 25 at 20:55
cskcsk
9,1451035
answered Jan 25 at 20:55
cskcsk
9,1451035
answered Jan 25 at 20:55
cskcsk
9,1451035
9,1451035
Thanks for the help. But does this only work if they are in different layers? When I tried it, I got a blank layer. All the overlapping features will be in the same layer.
– Chad
Jan 25 at 22:39
add a comment |
Thanks for the help. But does this only work if they are in different layers? When I tried it, I got a blank layer. All the overlapping features will be in the same layer.
– Chad
Jan 25 at 22:39
Thanks for the help. But does this only work if they are in different layers? When I tried it, I got a blank layer. All the overlapping features will be in the same layer.
– Chad
Jan 25 at 22:39
Thanks for the help. But does this only work if they are in different layers? When I tried it, I got a blank layer. All the overlapping features will be in the same layer.
– Chad
Jan 25 at 22:39
add a comment |
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1
Thank you for including "before" and "after" images of what you're trying to achieve. It made your question easy to understand.
– csk
Jan 25 at 20:58