To merge features based on specified attributes.

learn more… | top users | synonyms

0
votes
1answer
34 views

Combining rows in an attribute table based on field

I am using ArcMap 10.2.2 on a Windows 7 PC. I have shapefile range data for multiple species (multiple species in one layer), and this range data is accompanied by information relevant to the ...
0
votes
1answer
20 views

extract 1st level boundaries from GADM worldmap in QGIS

I need a world map, broken down to GADM 1st level. The obvious way would be to download all single country .shp files and merge them. But that is far too tedious of course. I tried the dissolve ...
2
votes
0answers
31 views

How to union linestring data distributed on multiple layers?

I have four shapefiles. Each contains a linestring as shown in the image. Each shapefile is represented as its own layer in QGIS. I would like to union these linestrings into one polygon which ...
5
votes
4answers
134 views

How to Unsplit/Dissolve multiple touching lines in Stream Network?

I am trying to dissolve multiple lines for stream networks into individual features. The dataset contains many stream networks so a complete dissolve of the whole dataset wont do as I would like to ...
0
votes
0answers
32 views

ArcGIS DissolveManagement Memory Problems

beside other tools I am using the dissolve tool in a python script. The input feature class (polygon) has about 140 MB. Running the script with python 32 bit (in CMD and in ArcGIS Desktop 10.2.2) ...
0
votes
0answers
37 views

Dissolving points based on easting and northing with statistic type first as aggregate function using PostGIS?

I have two points features having point_ID, Easting and Northing fields and want to dissolve based on Easting and Northing with statistic type aggregate as "first" for point_ID, as you do in ArcMap. ...
0
votes
0answers
17 views

Dissolving lines using iterate feature class (model builder)

I was wondering how I would build the model in order to dissolve multiple lines at once using the iterator. I have polygons over a line network that is supposed to represent roads, and I want to ...
2
votes
0answers
26 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 ...
2
votes
1answer
85 views

QGIS Dissolve tool re-projects and rotates layer

I'm trying to use QGIS (2.6.1-Brighton) to aggregate polygons according to an ID attribute. I'm using the shapefile of school district polygons in Michigan found here: ...
1
vote
3answers
107 views

Why dissolve creates many extra features?

I have a shp file in Arcmap 10 that has ~16600 polygons. Some overlap. I want any polygons that are overlapping to be dissolved into single polygons. I want non-overlapping polygons to remain the ...
2
votes
1answer
90 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
30 views

Spatial join by categories in QGIS

I am using QGIS 2.4.0 and I have a vector layer which contains a remoteness indicator which is broken up into 5 categories. I would like to turn this into a layer that has these 5 categories collapsed ...
3
votes
1answer
112 views

“Singleparts to multipart” vs. “Dissolve”

It seems to me that the vector tools "Singleparts to multipart" and "Dissolve" do the same things. Can someone confirm this, please? Or do I overlook something?
0
votes
1answer
27 views

Dissolving and returning values from primary lines

Im building a model and I need to dissolve line, that I marked in picture, to a line with field(NUMBER_OF_LINES) value of 2. Thsi filed represents how many lines were constructed to one line after ...
3
votes
0answers
75 views

Issue with dissolving a polygons layer in QGIS 2.4

I downloaded a dataset of roads and parks from OSM. I then buffered the roads and merged with the parks. Now - all i want is to dissolve / union all the features in the merged layer. I fail to do it ...
2
votes
1answer
119 views

QGIS 2.4 dissolve doesnt work properly, why?

I am used to work with ArcGIS and now I started to explore QGIS more. I have problem with dissolve function. I have administrative borders and I would like to dissolve them into higher administrative ...
2
votes
0answers
24 views

ArcGIS dissolve analysis output issues in geoserver wfs/ PostGIS

I have an ArcGIS dissolve analysis output (parcel data) that needs to be loaded on PostGIS and published as a wfs from geoserver. The issue is that the ArcGIS dissolve output shapefile, although can ...
1
vote
0answers
89 views

Is table with 20,000 rows and 5 columns too large for Dissolve of ArcGIS for Desktop?

Is a table with 20 000 rows and 5 columns too large for arc map 10.2.1? I have tried several things without success to dissolve this table based on one feature. The table was obtained from the ...
3
votes
1answer
115 views

QGIS 2.4.0: dissolve tool renders artifacts / errors

The dissolve tool (vector>geoprocessing tools>dissolve) renders some artifacts on shapes with high number of polygons. I’m using a shapefile with 3222 polygons and I’m trying to dissolve it using the ...
1
vote
2answers
67 views

Dissolve tool misses out two polygons

I'm trying to dissolve polygons based on a code number in the attribute table. It all works well, with an exception of two polygons that fail to dissolve - they literally drop out from the output. It ...
1
vote
1answer
27 views

Unsplitting Zpolylines without flattening vertical line segments?

Trying to figure out how to fully keep vertical line segments when using Dissolve/unspit lines... The first image shows the original Zlines in Arcscene The second image is the result of a Dissolve ...
4
votes
5answers
1k views

How to fix quickly a lot of geometry validity errors in QGIS?

I am working on ownership data at a US county level. I have one shapefile per county that contains thousands of tax parcels. I need to dissolve the polygons representing parcels owned by the same ...
0
votes
0answers
76 views

Statistics field in the dissolve tool not always accurate

When I run the Dissolve Tool using a Statistics Field (SUM being the statistic type) and proceed to check the SUM values for accuracy by comparing against the data in the original feature class, I ...
8
votes
2answers
350 views

Does dissolving features improve geoprocessing efficiency?

I have a large set of line data (>140,000 features). Is there a processing advantage, in either time required or (more importantly) memory used: to running Dissolve on the data before running ...
1
vote
1answer
67 views

Merge polygon based on other line shape file PostGIS

I have a polygon shape file and a line shape file. I would like to merge two polygons which shares the same border along with line shape. Finally the line should be removed in polygon shape file. In ...
1
vote
1answer
75 views

Postgres/PostGIS: Dissolve multiple fields with COUNT (Point shape)

I have loaded point .shp feature classes into Postgres 9.3 db, and enabled postgis,plpgsql,postgis_topology extensions. I'm looking to dissolve multiple fields within a single table 'TABLE1' and add ...
3
votes
2answers
86 views

problem merging polygons based on a column value - using Spatialite

edit: as I am unfamiliar with any tools I decided to try my luck with PostGis. I imported my data. and executed the query : create merged as select delomrade_code, st_union(geometry) from grunnkrets ...
1
vote
0answers
28 views

Polygon dissolve in DB

I have a polygon feature class with more than 100,000 polygons in DB2 table. I would like to dissolve them based on a single field to reduce the row numbers. Is there any commands / SQL in DB2 to ...
5
votes
5answers
452 views

Dissolving polygons fails on computers with small amount of RAM

When I'm trying to dissolve a polygon through an arcpy script the operation fails with the 999999 error on computers with small amount of RAM [~3 GB] (known issue). Unfortunately neither this, that ...
2
votes
1answer
38 views

ArcGIS Dissolve leaving feature snippets in dissolved polyons. Repair doesn't fix

I'm trying to dissolve some low-level polygons, but the result I'm getting has lots of little pieces of lines left floating around in the output polygons. I've tried doing "repair geometry" on both ...
2
votes
0answers
48 views

how to make a list of features constructing the dissolved feature?

I need to simplify my road network using the dissolve function to remove nodes not occurring on the intersections. the following code is doing that. arcpy.Dissolve_management(self.address_cor_layer2, ...
0
votes
1answer
201 views

How to dissolve naturalearth vectordata with gdal?

trying to use the workflow described by @aflaciano at How to render area that crosses 180°? I did the following: 1) downloaded and installed gdal-111-1600-x64-core.msi from ...
1
vote
1answer
88 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 ...
0
votes
0answers
115 views

Need advice on converting large geodatabase into shapefile or postgis

tl;dr: I have a fgdb w/ 800k tiny polygons representing high risk flood areas. I need to sum the area of these polygons within each administrative boundary (HUCs) and have a ratio per huc of high risk ...
1
vote
2answers
185 views

Merge Error: Not Enough Memory

I'm attempting to make a flood plain map for a school project, and am using FEMA Flood Hazard Symbology for the legend. I've dissolved by a Flood Zone Field, but am left with two attributes both named ...
1
vote
3answers
307 views

Why would Dissolve stop working in ArcGIS for Desktop?

I have an ArcMap Add-In that completes various geoprocessing steps, including Dissolve (using ESRI.ArcGIS.DataManagementTools.Dissolve). This tool worked at 10.0, but I just upgraded to 10.1 SP1 and ...
2
votes
2answers
1k views

Problem with merging and dissolving a shapefile in R

I am migrating from ArcMAP to opensource GIS. I've succesfully installed R and many packages in a Ubuntu 12.04 machine. I am used to linux and programming in C, but not to R and its syntax. I am ...
0
votes
1answer
182 views

QgsGeometryAnalyzer.dissolve problems

I am completely new to the QGIS python api and I am running into an error which I cannot solve when trying to use the dissolve class. I used the basics of the PyQGIS Cookbook. In my understanding ...
0
votes
1answer
265 views

Dissolve large dataset in ArcGIS and QGIS

I have more than 80k point data. I have created few buffer from 1 to 5 km of them. Now I want to get the covered area by 1 km to 5 km buffered range. For this I have tried to dissolve those individual ...
2
votes
1answer
61 views

How to dissolve geodatabase map across two subdivision levels in Arcgis 10.2

The existing polygon database contains attribute table with the following structure, and has three levels; country, state, and city (and many other countries not listed below). I want to dissolve the ...
2
votes
2answers
147 views

arcpy.Dissolve fails; need a arcpy dissolve to multipart workaround

I have a arcpy script in which I am using arcpy.Dissolve on a single feature class with multiple features to get a single multi-part feature in the output. The script is successful only part of the ...
1
vote
0answers
94 views

How to calculate Median of a table field in the Dissolve Tool of ArcGIS?

The Dissolve Tool of ArcGIS 10.0 has some statistical parameters as a type of calculation new values of each field in a process of dissolving of identical parameters . It has SUM, MAX, MIN, RANGE, ...
0
votes
1answer
86 views

Splitting hexagonal grid into segments, dissolve by location

I am a little bit frustrated because I want to do something I did 5 years ago and I can't figure out how to do it again. I am creating a turnover map of species communities using R and ArcGIS 9.3. As ...
1
vote
2answers
2k views

How to combine rows in attribute table using ArcGIS for Desktop?

I have an attribute table with three columns "FID" "Shape" and "Class" All records have the same shape (polygon). Each record has its own FID. I have three classes, "A", "B", or "C". I have twenty ...
0
votes
0answers
51 views

How to get the boundaries of a polygon by property

I have the cartography of my city (Santiago) and i need to obtain the nodes that conform the hull (not necessarily convex) of different districts, the boundaries. Each node has the same "DIS"( ...
1
vote
1answer
180 views

python dissolve by field error

I would like to dissolve a feature class by a field. When I run the code, I receive an error that says, "invalid topology [out of memory]" I have 16GB of RAM and terabytes available on the hard drive. ...
1
vote
1answer
114 views

MSSQL server 2008 dissolve sql query

I have a set of spatial objects in a MSSQL server 2008 R2 trying to dissolve adjoining objects where one of the attributes are equal. The table below is somewhat representative to my original table: ...
0
votes
0answers
92 views

Dissolve a Geometric Network in ArcGIS

I have a geometric network of water mains in ArcGIS. It it composed of a line feature class. I would like to dissolve it based on whether line segments share common endpoints only. So basically ...
1
vote
2answers
311 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
173 views

Aggregate/dissolve MySQL geometry

On Centos, I have a MySQL 5 database with a MyISAM table that has a geometry column with a spatial index, containing US county boundaries. Trying to combine/aggregate/dissolve some of these into as ...