To combine two or more parts into a larger whole.

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16
votes
2answers
23k views

How can I join several raster files using QGIS?

I'm new to QGIS. How can I combine multiple raster layers into one layer? The raster images are of different areas with very little overlap. The goal is to bring numerous town plats into one project. ...
11
votes
1answer
2k views

Fixing orphaned holes in R

I'm trying to perform a union on a common field after merging two adjacent shapefiles. The shapefiles end up with at least one thin sliver of space between them. When I attempt a union I get the ...
11
votes
1answer
4k views

Merge Multiple Tables into a New Table in PostGIS

I am looking to merge a number of individual tables into a new table in PostGIS. This is an easy task when working with Shapefile data, but I am unsure how to do this in PostGIS. Any help would be ...
9
votes
2answers
8k views

Is there a difference in performance between Merge and Append in ArcGIS?

Often I find myself in a situation where I don't care whether or not my tool produces a new feature class, but I do care how long it takes to combine all of my large datasets. Does it take longer to ...
8
votes
4answers
3k views

Open source software to merge large shape files

Some background: I have 2 polygon shape files with approximately 500,000 records each. The two files are identical in terms of field structure. Using ArcGIS 10.0 I can'nt merge these two files using ...
8
votes
4answers
20k views

How to Merge/Dissolve Polygons By Common Attribute Field in QGIS?

I have joined corresponding Local Enterprise Partnerships table data into a polygon shape file containing UK Local Authorities. How do I Dissolve or Merge the the Local Authorities polygons by ...
8
votes
2answers
1k views

How to add vertices to existing linestrings?

If I have Linestring(1 2, 1 5, 1 9) and a Point(1 3) Is there any function that can merge linestring and point preserving the order so output would be: Linestring(1 2, 1 3, 1 5, 1 9)
7
votes
3answers
684 views

Merge images first, or georeference first?

I'm wanting to georeference and vectorise some features from scans of the OS 1896 Town Plans that I have purchased from the NLS (http://maps.nls.uk/os/london-1890s/info.html). The scans provided are ...
6
votes
1answer
5k views

How do I edit shape file attribute tables so they all have the same information?

I am trying to merge several pipeline shapefiles using GEOMERGE but it cannot complete the function because they have different column definitions. So I need to edit the attribute tables so that ...
6
votes
3answers
3k views

Which is more efficient process in ModelBuilder - Merge/Dissolve or Union/Dissolve?

I'm creating a model which combines four very large files and dissolves them. At the moment, my workflow uses the Merge tool and then the Dissolve tool. However, I was wondering if using the Union ...
6
votes
3answers
2k views

Merge Spatially Coincident Features in the Same Feature Class

I need a way to programatically merge grid cells (polygon 15x15m) that are directly on top of each other and add together some of their attributes. I am working in ArcGIS 10.1 with the data stored as ...
5
votes
4answers
15k views

QGis: Merge intersecting polygons into one which are part of the same feature

I'm not a GIS professional so I hope I use the correct wording, at least I hope you understand my question. Let's say there are 5 polygons in the feature A. In the shape file there are more ...
5
votes
2answers
418 views

Merge uniquely named point shapefiles in 50,000 different folders into a single layer

I have point shapefiles in 50,000 different folders (each shapefile file name is unique) - about 33,400 shapefiles (not all folders will have a point shapefile). I like to open the point shapefile in ...
5
votes
1answer
154 views

Merging .asc files = “The command line is too long”

Having problems merging LiDAR .asc folder files to produce a single GeoTiff file. I have followed various instructions e.g. the 2 methods of selecting input files for merging .asc files using ...
5
votes
1answer
2k views

How to merge shape files with attributes from a python script in QGIS?

I have some shape files. They are all the same kind of shape and all have the same attributes. If I wanted to merge them manually the "Vector/Data management tools/merge shape files to one" works ...
5
votes
2answers
1k views

Correctly merging DEM rasters and eliminating edge effects

I'm using 10m DEM rasters from the NRCS Data Gateway for a large portion of California. The problem is some strange tiling that appears after merging, but isn't present in the original data (before ...
5
votes
2answers
5k views

How to merge multiple file geodatabases into one file geodatabase?

I have created a file geodatabase that has several feature data sets, feature classes, and domains. I have created a map with the file geodatabase added to it, converted the map to ARCPAD AXF format ...
5
votes
2answers
592 views

Extract certain area of contours/satellite images

I have 2 satellite images (jpeg2000 format) and 2 xyz-files from the same area. I am trying to extract certain region from the area including contour lines and the satellite image in order to import ...
5
votes
1answer
305 views

How can I match the cells of two rasters?

I have many raster files each one containing information that is different from the others (e.g. one contains information on rain, the other on altitude, and another on land use). The cells in each ...
5
votes
1answer
1k views

Using ArcPy to batch merge based on shapefile name?

ArcGIS 10 SP4 Python 2.6.5 I have quite a few shapefiles that are in many different directories. I'd like to pull out groups of like shapefiles, merge them, and move the results into a FGDB. I've ...
5
votes
1answer
56 views

What is the best way to merge lots of small adjacents polygons ? (POSTGIS)

I am looking for a way to merge lots of small adjacents polygons. I have this kind of features: So if my polygons are adjacents AND have the same color attribute then I want to merge those ...
5
votes
0answers
746 views

PostGIS: Merge any and all adjacent polygons

I would like to do adjacency tests on a parcel (polygons) layer and merge them if they fit certain criteria (could be size). Per the picture below, I would like to merge polygons 1,2,3 and 4, but not ...
5
votes
0answers
141 views

How to add shapefile name as attribute during merge? [duplicate]

Possible Duplicate: How to add field with filename when merging shapefiles with ogr2ogr? I have more 200 shapefiles with a unique name. I would like to merge all of these together and save ...
4
votes
2answers
3k views

merge shapefile using ogr2ogr and retrieve the attribute of both

Ciao, I have two shape files that I want merge (overlay/intersect) having in the destination the attributes of the two sources file. ogr2ogr file_merged.shp tl_2010_us_uac10_conus_albersUA.shp ...
4
votes
2answers
202 views

Shapefile Naming conventions in ArcPy?

I have shapefile named `band-tailed_pigeon.shp which is fine and no problem on displaying or geoprocessing on Desktop but in ArcPy when I try to merge some layes to it I am getting this error ...
4
votes
2answers
1k views

Merging polygons that intersect by more than a specified amount

I am working with a dataset that contains a subset of property boundaries in a local government area, thus my dataset is made up of several thousand properties but not all are touching. Since it is a ...
4
votes
2answers
116 views

Problem Merging multiple shapefiles with different CRS in QGIS

I am trying to merge multiple shapefiles into one, but I encounter one error, not all of my shapefiles end up merged. I am able to load all of my shapefiles but when I attempt to merge them, the ...
4
votes
3answers
1k views

How can I convert a set of ShapeFiles to an OSM file?

How can I convert a set of ShapeFiles to an OSM file?
4
votes
1answer
2k views

How to merge many shapefiles in different folders?

Directory structure is basically as such: county\City\prep\POI\Completed\C1, ...C2, ...etc\ I'm trying to write a script to go through the *\Completed*\POIS.shp and merge them all together, at a ...
4
votes
1answer
60 views

Merging Features

I want to merge features of a vector layer into one single feature using the python console. Somewhere I found the following solution. However it does not seem to work for me. When I execute the ...
4
votes
1answer
1k views

merge selected features and programming

I have a shape file with UK districts and unitary authorities. In the past, using commuting patterns, I worked out a new geography which is close to travel to work areas. I now would like to create a ...
4
votes
2answers
155 views

Merging rasters in QGIS?

I have 3 modis tiles that I want to merge together. They were all reprojected in the same CRS (from sinusoidal to WGS84 UTM zone 32 N), but I cannot succeed. I have tried with merge and virtual ...
4
votes
1answer
473 views

Merge tif files with python

I'm also having problems with running gdal_merge.py within another python script and I cannot run it. I already checked a similar problem here. My example is as follows: First I set my workspace and ...
4
votes
1answer
483 views

Failing to merge rasters in QGIS

I am new to QGIS but have some familiarity with other GIS software (namely ArcGIS). I want to merge a number of LiDAR digital elevation model (DEM) tiles (specifically, 30 individual tiles) to ...
4
votes
2answers
2k views

Merge an entire Geodatabase in ESRI ModelBuilder

How can I merge an entire Geodatabase in the ESRI (ArcView) ModelBuilder? I have several FeatureClasses created into the GDB and in the model I plan to merge them all. Right now I have imported all ...
4
votes
1answer
346 views

Why are my calls to SAGA routines in QGIS not working cross platform?

The ability to write and run cross platform scripts for QGIS using python is OUTSTANDING! However, when I try to run the SAGA:MERGESHAPESLAYERS algorithm from a python script it works fine in windows ...
4
votes
1answer
303 views

Merge polygon without attribute (in field) with nearest polygon with attribute

In the image you can see districts in BLUE with attributes (name of district) and small pieces in RED. The red polygons belong to the blue and I want to merge them. The RED are only towards the ...
4
votes
1answer
475 views

How to join data from NHGIS to make choropleth maps in R/ggplot2?

I have downloaded shapefiles of county/state boundaries and census data keyed to those shapefiles from the NHGIS. Both the shapefiles and the census data have a GISJOIN column to be used for merging ...
4
votes
1answer
774 views

Merging partially overlapping polygons into a table in PostGIS

I have a couple of tables (three) with polygons (landuse coverage in this case). Within each table, there is no overlap, but between tables there might be a lot of overlap. I would like to combine ...
4
votes
1answer
344 views

How can I avoid reprojection gaps when merging DEM rasters?

I have two raster DEMs in same resolution I want to bring together. I was using the merge-function in SAGA, GRASS and QGIS but I always get the following result: What do I need? Where could the ...
4
votes
1answer
165 views

Merging multiple feature classes in file geodatabase with ogr2ogr?

Is there a way to merge multiple feature classes into one feature class in a geodatabase with ogr2ogr? If this isn't possible with ogr2ogr, is there another method? I'm using the ESRI File Geodatabase ...
4
votes
0answers
26 views

“Merging” 2 layers of LineString with splits at intersections

I would like to "merge" 2 networks of lines and these lines need to be split when they intersect. With pictures it should be clearer : What to do: if a black line intersects a red line, they ...
4
votes
0answers
120 views

Merge Raster Layer Specific Order in Graphic Modeler

I'm using the Graphic Modeler/Processing Modeler to automate a process. The last step in this process is Merging three different Raster Layers. I'm using the "Merge Raster Layers" from Saga 2.0.8. Is ...
3
votes
2answers
2k views

Merge geojson polygons with WGS84 coordinate

I have a Geojson file with some adjacent polygons and I want to merge them into one. I know it's a recurrent question but I can't find information for polygons with latitude and longitude coordinates ...
3
votes
1answer
9k views

How can to merge DEMs in ArcGIS for Desktop 10.2?

I'm trying to merge some dems downloaded from USGS. When I used arcgis 9.2 there was an expression to be used in raster calculator to do that. I used it again but unfortunately it doesn't work in ...
3
votes
3answers
131 views

How can I join two polygons that are within the same layer in QGIS?

I have two polygons in QGIS that are within the same layer and I want to merge them so they are not in two different polygons, which means that the gap between them sould not exist. How do I do that? ...
3
votes
2answers
116 views

How to delete overlapping inside same polygon?

I have same polygon partially overlapped: How to delete overlapping and merge it to same area? I am using QGIS 2.4.0.
3
votes
2answers
73 views

How to rename several layers at the same time?

I have got some GPS tracks (MultiLineString). As I import them to QGIS, they look like this: I would like to merge them and to do so, I have to rename all of them like this (picture 2) otherwise an ...
3
votes
2answers
134 views

How to Merge dbf files?

I'm beginner in python and learning it with examples. I have 100s of dbf tables like Type value1 value2 Type value1 value2 A 3 1 and A 5 7 B ...
3
votes
1answer
811 views

How do I merge DEM rasters correctly?

I've been struggling with this problem for awhile. Here is a curvature raster to illustrate the problem. I'm using 10m DEM rasters from the NRCS Data Gateway for a large portion of California. The ...