To combine two or more parts into a larger whole.

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10
votes
2answers
11k 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. ...
9
votes
1answer
2k 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
3k 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
2answers
811 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
374 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 ...
5
votes
1answer
3k 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 ...
5
votes
3answers
780 views

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

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 ...
5
votes
1answer
163 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 ...
5
votes
2answers
2k 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
416 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
76 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
745 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
3answers
1k 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
0answers
133 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
1k 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
212 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 ...
4
votes
1answer
653 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 ...
4
votes
1answer
975 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
874 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
1k 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
104 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
144 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
290 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
254 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 ...
3
votes
2answers
201 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
160 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 ...
3
votes
1answer
1k views

Use model builder to select layers by attributes, dissolve them and then merge them

StackExchange team, I would like to reclassify polygons, I want to combine smaller polygons into bigger polygons based on their ID (each polygon has a unique ID). I want to regroup ~800 polygons into ...
3
votes
3answers
689 views

How to merge a large amount of polygon-features in a script?

We have a very large shapefile with over 30000 features and want to merge it with a script on a server. Currently we try it with QGIS, but the processing takes way too much time. Is there a way to do ...
3
votes
1answer
674 views

Merging raster data with different resolutions

I need to merge different raster datasets which have one layer and contain discrete values to a layer stack. The resolutions of the data can have any value so not only multiples of the resolutions ...
3
votes
3answers
301 views

A linestring merger algorithm

I'd like to merge linestrings which touch, but do not cross. The linestrings share the same SRID and come from a PostgreSQL 9.2/PostGIS 1.5 database. Within the table I query are several line strings, ...
3
votes
5answers
1k views

Automatically download and merge webmap tiles into one big image?

Is there an easy way to download a bunch of web map tiles (in /z/x/y.png format) and stitch them together into a single large image? I could probably script this using ImageMagick, but would prefer ...
3
votes
3answers
119 views

Automated way to join

I have river networks (polyline) of several adjacent countries as shapefiles that almost match up at the borders, but not quite. Is there any way to automatically connect them to a consecutive river ...
3
votes
2answers
734 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 ...
3
votes
1answer
384 views

How to combine lines from different sources reperesenting the same road network but with slightly different geometry?

Here is my problem: I have got two layers of polylines which represent the same road network but they are from different sources and have different geometry. The two layers are mostly the same tracks ...
3
votes
2answers
130 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 ...
3
votes
1answer
62 views

Merging .dbf Tables in Python w/o merging all fields of same name

I'd like to merge several tables together using Python. They all have the same field names: "TIME", "X", "Y", and "VALUE". I would like the "VALUE" fields to remain separate when merged, so that the ...
3
votes
2answers
189 views

Merging DEMs of different grid size

I'm trying to merge two grids with different cell size. One has a cell size of 10m and the other 50m. The 10m one covers a subarea of the 50m one. I know that the most accurate one is the 10m one and ...
3
votes
1answer
711 views

How to merge several google map images into one?

I want to have a high resolution aerial photo of a catchment area. I took some images from google maps and georeferenzed these and saved them as a layer file. but how can I merge them now that I have ...
3
votes
1answer
344 views

ArcPy merge datasets with slightly different fields

i have many (>15) shapefiles which have slightly differing fields. s1: (Name, age, layer_1, ...) s2: (Name, age, layer_1, layer_2, ...) ... s_n: (Name, age, layer_1, layer_1_extra, ...) I want to ...
3
votes
1answer
595 views

How to merge Waypoints from many GPX files?

I have a large number of Waypoint-layers (gpx) and would like to merge them. Is there a way to do so using QGIS? Thank you!
3
votes
1answer
165 views

shapefile batch clip and merge combined

I have two shapefiles, one is polyline, the other polygon. For each polygon I would like to clip the polyline vectors inside. Using arcpy I already found part of a possible solution: ...
3
votes
2answers
767 views

Merging Shapefiles With Geotools

I am trying to merge some shapefiles with different schemas in geotools. Im aware of ogr2ogr, but for now I would like to figure out this problem with Geotools. The steps I'm taking are: 1) Create a ...
3
votes
1answer
66 views

Merge different Landsat scenes in Grass GIS

I am new to Grass GIS, and I really need some help in solving this issue. I have 17 scenes from Landsat8 covering an area. I have created color infrared images of bands 5,4,3 and now I want to merge ...
3
votes
1answer
378 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 ...
3
votes
2answers
367 views

In PostGIS, how do I merge a multilinestring into a single linestring, keeping the pieces in proper order?

I have a multilinestring made up of several pieces, some of which are facing the wrong direction. (Accessible here: http://pastebin.com/89Zcixv5 ) I think what I'm looking for is some utilization of ...
3
votes
2answers
156 views

Merge two geodatabases with identical structure

I'm using an ArcGIS addon which stores all created data (shapes and tables) in a gdb. The addon is made for single user use but to safe time I want to split the work with someone else. After that I ...
3
votes
2answers
738 views

How to join lines in QGIS for later using “lines to poly”?

After successfully merging lines (using snapping) with merge_selected_features i got nice result - one merged line. Next thing was to make polygon from created merged line. Result is not nice - it ...
3
votes
0answers
28 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. ...
2
votes
3answers
510 views

Can ArcGIS only merge two shapefiles each time?

I need to merge multiple point shapefiles (in the same directory) into one point shapefile. After inputting these shapefiles and merging it, I found the final output only contained the data from two ...