To merge features based on specified attributes.

learn more… | top users | synonyms

1
vote
0answers
25 views

PostGis - st_union polygons, keep sum of attribute

There are multiple My current query is: SELECT (ST_Dump( ST_Union( way ) )).geom AS way, 10000 AS way_pixels FROM ( SELECT way, way_pixels, ...
3
votes
1answer
513 views

Problem when executing Dissolve method in ArcEngine

I'm always having a problem in GP.execute() when trying to execute this method. Here is my code: Friend Function DissolveFeatures(ByVal pInFLayer As ESRI.ArcGIS.Carto.IFeatureLayer, ByVal ...
1
vote
1answer
195 views

How to dissolve by two fields?

I have a shapefile with many polygons in it. I want to dissolve by two fields. Is there any possible way to dissolve this by NAMA_KPH and PL15_ID?
2
votes
1answer
200 views

How to dissolve adjacent parcels by same owner but include those parcels located across the street with the same owner?

In trying to determine the total contiguous stream length per landowner, I dissolved parcels by parcel owner name attribute and intersected these dissolved parcels with streams. However, dissolving ...
1
vote
1answer
310 views

ArcGIS Dissolve gives Error 999999 on one computer but works on a different one

I'm trying to run the geoprocessing tool "Dissolve" on a single feature class in a File GDB, yet I'm getting the error 999999 "the operation was attempted on an empty geometry", but there are no empty ...
3
votes
1answer
110 views

Converting Road Lines to a Binary Raster Image

I got road data from the USGS database and imported it into QGIS. And I want to transform it into a binary raster image that looks like this in QGIS (this is only a processed screen shot but I want ...
6
votes
1answer
153 views

Create buffer based on polyline without line end caps and without dissolving the created polygons in QGis

I have a projected line layer (Shapefile) in QGIS. For every line segment I want to create a polygon without line end caps. The resulting polygone should not be dissolved to a single one. I tried ...
1
vote
3answers
37 views

ArcGIS Dissolve/SQL group by

I have a GIS layer that has thousands of Facility IDs. For each Facility ID there can be multiple Chemical ID's. For each chemical ID there is a maximum of 3 zone types. Zone A, B, C. But there is not ...
13
votes
2answers
21k views

Merging polygons in shapefile based on field values?

I have a shapefile with a lot of polygons in it. These polygons are grouped into a category: district. How can I merge the polygons based on the same name of the category within this shapefile?
1
vote
1answer
30 views

ArcGIS 10.3 Dissolve tool splitting up lines, not dissolving them

I have noticed strange behaviour with the Dissolve tool so tried a test on three line segments, snapped to the same central point. The line segments each consist of exactly two vertices i.e. the end ...
1
vote
0answers
46 views

SAGA Gis and QGIS: difficulties in dissolving polygons

I am new in using GIS and I'm having some problems in properly dissolving some polygons. In particular, I have a single layer with about 3,000 polygons (protected areas), some of which overlap (the ...
0
votes
1answer
22 views

Traces outside polygons after merging several polygons together

I'm using ArcMap 10.3.1 I have a polygon shape file for areas upstream of 5 monitoring sites. I used dissolveand merge to merge all these polygons together. You can download the resulting shape file ...
3
votes
1answer
35 views

Assigning common field value to segments between two points using ArcGIS for Desktop?

I am using ArcGIS 10.3 for Desktop. I have a shapefile with polylines connecting points. Instead of having one single polyline connecting two points, there exist a number of consecutive segments ...
2
votes
0answers
11 views

How to create one attribute containing multiple adjacent parcels?

I'm trying to upload town parcel data to my Garmin GPS from Esri. Garmin registers each attribute as an entirely different file, and requires you to 'turn on' each file to display it on the GPS. This ...
2
votes
4answers
103 views

merge overlapping polygons with spatialite

The green points, buffered by one of the point attributes, should result in the three areas outlined in red (a table with three rows): I'd like to do it in spatialite. How can I do that? If it's ...
2
votes
0answers
24 views

Unsplit line Reversing Line Direction [closed]

I am using the unsplit line tool and I noticed that the direction of the lines with multiple segments is getting switched the opposite direction while the single sections seem to continue in the ...
3
votes
0answers
35 views

QGIS Dissolve skips polygons

I'm having trouble with the dissolve function in QGIS. Is it because of an overlap? It's not a GRASS layer, just shapefiles. I'm new with GIS software in general. Searched for similar problems but ...
6
votes
4answers
2k views

Improving upon ArcGIS Buffer/Dissolve performance?

I'm wondering if anyone else has experienced significant performance penalties when using the ArcGIS buffer function with the 'dissolve' option on point features. My dataset is a shapefile of 260 ...
1
vote
0answers
41 views

ArcPy Dissolve Statistics Fields - fixed into variable

How can I change this fixed POP column into my variable: field = parameters[1].valueAsText. It says syntax error everytime. StatField = "POP MIN;POP MAX" arcpy.Dissolve_management(in_features, ...
3
votes
0answers
113 views

Dissolve Management in Python

I have a simple code that is pulling together polygon shapefiles from a Windows folder and merging them together into a single shapefile. In the same code, I want to add a dissolve command. My fields ...
1
vote
1answer
93 views

Merge and dissolve overlapping polygons?

I have a situation in which I have both network buffers and circular buffers around the same points (as separate feature classes), and I want to merge the buffers and dissolve into one polygon for ...
4
votes
4answers
131 views

QGIS classifying vector data

I am trying to classify a shapefile based on rule set, following this tutorial. This is the result: What I want to ask is: 1. How to insert the classification result (water, land etc) into the ...
1
vote
1answer
42 views

Arcgis dissolve output has greater area than inputs

I've been using dissolve to successfully merge polygons (which may or may not overlap) representing mining tenements so that I can calculate their total coverage area (using the geodesic area ...
1
vote
2answers
1k views

Looking for dissolve algorithm for Javascript

I have three adjacent polygons that together make up a larger shape. I need an algorithm that will dissolve the internal borders leaving only the outside border. An example would be a group of ...
2
votes
1answer
636 views

Why does Merge then Dissolve return ERROR 000732: Input Features: Dataset … does not exist or is not supported?

I'm not sure why I'm running into this problem. I thought it might have something to do with the merged file being locked or open, but I don't see a "LOCK" file being created in Windows Explorer. I'...
1
vote
3answers
32 views

Dissolving while retaining field informations in the same entry instead of multiple entries

I have 1520 covenants. Many covenants have more than 1 VM symbols attached to it, currently showing as rows. EG. Covenant #97 has 4 VM Symbols, with the VM Symbols 1, 67, 117 and 171. How do I change ...
1
vote
1answer
59 views

How to dissolve polygons that overlap both on each other in QGIS?

I have two layers of polygons with landcover classes(meadows, cropland, forest, ect) They overlap in both directions, i.e like a zipper. I need to dissolve them by one attribute (Class) so I can have ...
5
votes
1answer
98 views

Dissolve overlapping polygons according to percent overlap using PostGIS?

I have a shapefile with convex hull polygons, all in the same layer/shapefile. Some of the polygons overlap (not duplicate polygons). I would like to dissolve/union the polygons which overlap with ...
1
vote
0answers
45 views

Merging multiple fields with same parcel id yet different attribute values, while keeping all fields?

I am using ArcGIS 10.3 for Desktop. I have a property parcel layer that when Intersected, each parcel is broken up into hectares of different land covers. My question is can this be merged (or ...
4
votes
3answers
3k views

Why is the Dissolve Tool not working?

I'm still having trouble with the dissolve tool and I've tried all of the solutions offered here including moving the process from the background and repairing the geography. I've also tried amending ...
5
votes
2answers
89 views

Identifying a cluster of polygons based on attributes

I'm trying to identify a cluster of contiguous parcels that, when combined, add up to at least a given size and, when combined, have an assessed property value less than a given $ amount. I have a ...
3
votes
1answer
309 views

Query to Dissolve Nearby Polygons on Hive

I am using the ESRI spatial framework for Hadoop, that extends Hive to use spatial types and operations. My objective is to translate a set of simple queries on PostGIS into Hadoop, in order to ...
2
votes
1answer
4k views

Dissolving two different buffers together so not overlapping using ArcGIS Desktop?

I am trying to find out how many registered sex offenders live within 2,000 feet of a school/park in a specific county. The park buffer and school buffer are dissolved but not together. I am also ...
0
votes
0answers
361 views

Dissolve using GDAL/OGR?

I'm trying to dissolve a shapefile according to a field using Python 2.7.10 and I don't want to use ArcPy. Is there any way to do this using GDAL/OGR?
3
votes
3answers
60 views

Dissolving redundant fields in ArcGIS for Desktop?

I have a map of a small neighbourhood. I'm trying to label these but because of the grid being squares the objects are split and therefore showing two two or more labels of each location. I'm trying ...
2
votes
0answers
51 views

Combining adjacent shapefiles and merging neighbor polygons currently divided by quad boundaries

The project I'm working on has been mapping ecological sites in ArcGIS on a quad-by-quad basis for the past 10 years. When entered into GIS, each quad has its own shapefile and the sites are cut off ...
2
votes
2answers
177 views

Dissolve line segments in QGIS if they touch and fall within the same class. (tools or script?)

I have line segments that have the following 3 attributes (Class, start_point, end_point). I would like to merge/dissolve line segments that fall within the same class if they intersect (touch). i.e. ...
3
votes
2answers
188 views

Dissolve a polyline feature class so that touching features dissolve into a single feature

I'm trying to dissolve a polyline feature class so that spatially intersecting features become a single feature. When I run the Dissolve tool, setting Create multipart features and Unsplit lines both ...
3
votes
2answers
447 views

Stratified Random Sampling with large dataset in ArcGIS?

I want to create a Stratified Random Sample with a land cover classification map. The purpose for the Stratrified Random Sample is to produce an Accuracy Assessment. I am using ArcGIS 10.2 with access ...
5
votes
3answers
124 views

Dissolve overlapping polygons in SAGA

I've got the following (2D!) situation of overlapping polygons: I would like to have the polygon border dissolved such that I have only one polygon left. I thought this was a definitive case for ...
3
votes
2answers
113 views

Dissolving with PostGIS slow and results in large table?

I am having a table of polygons with some 15 Mio. records. The polygons hold an attribute called "dn" with integer values between 0 and 6. My goal is to simplify that table so that polygons below a ...
1
vote
1answer
82 views

Dissolving in ArcMap gives “Invalid Topology [Duplicate Segment.]”

I am attempting to use the dissolve tool on a shapefile, but it fails with the error: ERROR 999999: Error executing function. Invalid Topology [Duplicate segment.] I tried checking and repairing ...
1
vote
2answers
457 views

Dissolve multiple polygons into one based on background layer

I have a layer of regions (25 regions) and a layer with thousands of polygons. I want to dissolve this into 1 polygon for each region (so I can calculate the exact geometry). I used the dissolve tool ...
1
vote
1answer
65 views

Invalid parameters using ArcPy dissolve and statistics_fields

I am trying to use the Dissolve_management tool using ArcPy. I keep getting an error that reads "Parameters are not valid.", and I cannot figure out where I am going wrong. Here is the code: env....
1
vote
2answers
71 views

Dissolving contiguous clusters of polygons and identifying them separately in attribute table of ArcGIS for Desktop?

I have a layer comprised of about 500,000+ simplified polygons that resulted from converting raster cells to polygons with raster cell values assigned to them. When I select the resultant polygons by ...
0
votes
0answers
96 views

Dissolve in python script not working correctly

I have a python script that merges 12 shapefiles into 1 shapefile with about 75k total records. I want to dissolve the latter shapefile on a particular field, and SUM another field, so my final ...
0
votes
0answers
47 views

Mulitpart dissolve equivalent with SQL Server

SQL Server 2012 has introduced a handy set of geographic aggregate functions that is well summarized here. Among the aggregate functions are UnionAggregate and CollectionAggregate. UnionAggregate is ...
3
votes
0answers
119 views

Dissolving polygons in a large dataset

I need to dissolve polygons by the ID attribute in a large dataset (+-1gb shapefile). I have been struggling to find an efficient method to do this. I have tried the following methods: Postgis ...
6
votes
1answer
223 views

Deleting 'garbage' nodes after polygon dissolve

I work with QGIS 2.10.1 on Windows 7 (x64). I have dissolved polygons from an attribute value and the polygons geometries being not perfectly joined together, I get some 'garbage' nodes I need to ...
2
votes
1answer
125 views

PostGIS: How to dissolve vector data

I have a few scenarios where I need to dissolve vector data, and I'm wondering how to do this using PostGIS. What would the queries look like to perform these operations? Below I'll describe the ...