A spatial operation in which two or more maps or layers registered to a common coordinate system are superimposed, either digitally or on a transparent material, for the purpose of showing the relationships between features that occupy the same geographic space.

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4
votes
1answer
478 views

Check/uncheck overlays in groupedlayercontrol.js

In a Leaflet-based app I have create several overlays, grouped with leaflet.groupedlayercontrol.js, as shown in this image: Everything works well, but I need to uncheck certain layers, allowing the ...
0
votes
1answer
75 views

Is it possible to join two different data sets in QGIS?

I have one data set which contains all federal states of Germany. The other dataset is about the population density in every km² in the EU. My goal is now to join these two Datasets so I can answer ...
1
vote
3answers
971 views

“Identity” overlay in QGIS?

I have two polygon layers I'd like to overlay using QGIS or another open source tool. What I want as output is a polygon layer with the extent of one polygon, but with each polygon in that layer ...
-3
votes
1answer
121 views

Same coordinate system - shapefiles don't overlap [duplicate]

I have two shapefiles and two rasters (dem), and while I put them in the same coordinate system (Greek grid), it seems that they don't overlap. But one is the boundaries of a county, and another the ...
4
votes
2answers
391 views

Determining area of county land mass without water features using ArcGIS Desktop?

Here are the layers that I have: State / Province polygon file (With Area Field) County / Ward polygon (with no area field), but all the polygons are within the state boundaries Water ways for the ...
1
vote
1answer
272 views

Calculating coverage of vector polygon over other polygons?

I have a shapefile file that contains a LiDAR footprint and I'm trying to figure out how much a county is covered by the LiDAR footprint. Two separate shapefiles. The attribute table for the county ...
4
votes
1answer
478 views

How to get a GML overlay on Google Maps?

Anyone know how to get a GML file to show as an overlay on Google Maps? To be honest I don't know my GML from my KML, or my ETRS89 from my WGS84, as this topic is completely new to me. A bit of ...
2
votes
0answers
265 views

GRASS v.overlay.or Error when trying to split a polygon with a line

I am using the Grass plugin in QGIS for Windows (1.8.0). I am trying to split a polygon with a line feature. I am using the v.overlay.or function within the QGIS Grass plugin. I have the line layer ...
1
vote
0answers
45 views

Polygon overlay, calculating changes, in QGIS?

I'm trying to create a relationship file between two vintages of census tracts. (in this case, 2010 and 2013.) Reason being to load ACS (American Community Survey) census data and use weighted means ...
0
votes
1answer
78 views

How to overlap a base map with a png map (format .pgn) on QGIS-Pisa?

How can I overlap a relief base map taken from maps-for-free.com and this png-formated map so that I can get a resulting map with relief of the 1st map and boundaries of the 2nd map ?? I'm a ...
1
vote
1answer
51 views

Determine the range of values in one raster associated with certain values in another raster

I have two rasters, one with thematic data, and the other with continuous data (floats). I am trying to calculate/determine the the range of float values associated with the different classes in my ...
1
vote
1answer
43 views

How can I remove feature selection from my layeroverlay in mapguide API?

I can add feature to my layeroverlay on mapguide API, but I don't know how to remove it. Can you help me find a method to remove a feature from a selection ? This is how i add features to my layer : ...
2
votes
2answers
76 views

Selection on Overlapping Polygons

I have converted a CAD file to GIS format using GIS (from .dgn to .shp)... In one layer I have polygons in which a smaller one is on top of the larger polygon. I can see both polygons however when I ...
1
vote
2answers
59 views

How to overlay subset of one data set onto another

I have two data sets: one for Thurston County, Washington and one for all of Washington state. I created a map of hydrology features in Thurston County, and now I want to take the data from the ...
0
votes
1answer
131 views

Closer for measureToolTip, openLayers 3

I want to add for my map measure tools. I added distance for line and square for polygon. Also i added erase for drawed element, but i can't to clear measureTooltip. First I try do it with Overlay....
1
vote
1answer
18 views

Redefined Topo and Shape file still wont overlay

I am trying to overlay a topographic map that is a raster and a road shape file. The road shape file was originally not defined. I defined the projection to NAD_1983_2011_Contiguous_USA_Albers and I ...
0
votes
1answer
121 views

Making a KML layer “always on”

Is there a KML tag or specification by which you can force a given layer (specifically, a screen overlay) to be "always on", in that there is no way for the user viewing the file to make that layer ...
2
votes
1answer
34 views

How to show overlay in layout legend [closed]

I am displaying three different layers on a map, essentially three separate habitat types. Each have their own colour. In cases, 2 or 3 of the layers overlap in part (essentially showing where ...
2
votes
1answer
187 views

Display LiDAR data in E00 (interchange file) on maps

I have Lidar data in E00 files (interchange files). Can I overlay them on some maps like say Bing maps or Geoserver with OpenLayers? If yes, what is the right way of doing it?
0
votes
0answers
59 views

How to make a polygon and point shape file line up to do a spatial join?

I have a polygon with a North_America_Lambert_Conformal_Conic coordinate system and a point shape file which had a WGS 1984(DD) coordinate system. I defined projection and projected both of them to ...
6
votes
1answer
200 views

Extracting the pixelwise proportion of classes of a finer raster in a coarser one

I have two rasters, one has a 1 km resolution. The other has a spatial resolution of 30 m. This latter pixelwise is a classification. I want to overlay the 1 km raster on the classification raster and ...
0
votes
0answers
43 views

Polygons Present in another Polygon (Selection/Attribute Transfer)

I have 2 layers, Sugar Data and Surveyed Parcels. My interest is to include 2 new fields in the sugar data (lot & plan) which is present in the surveyed parcels data. Im using Arc Map 10, can ...
1
vote
1answer
281 views

Overlaying grids with a polygon to determine the average value of the overlapping grids for that polygon

I would like to add the average, minimum and maximum value of, let’s say soil moisture (variable "value" in my case), to each NUTS3 region (= a NUTS3 region is a polygon of a certain small area in ...
4
votes
1answer
184 views

Grid vs. Polygon Overlay in R gives different results than in QGIS

I have a shapefile of range polygons. Each colored set of polygons represents a different group of species/genera/whatever. I next overlay a 5x5 grid onto this map. And then use join attributes by ...
4
votes
1answer
268 views

Generate grid shapefile in R

I have the following shapefile of a 10x10 degree latitude/longitude grid that I created in QGIS. I can read it into R using the rgdal package. Grid<-readOGR(".","GridShapeFile") It has the ...
1
vote
0answers
49 views

Overlapping polygons with buffers and need to keep associated data [closed]

I have a point file that has been buffered by 400m. I have overlayed it on top of a polygon file and I need to keep all data that overlaps for each point. What is the best way to do this? I have ...
8
votes
1answer
7k views

Openlayers wfs vector layer

I'm trying to add a vector layer with a wfs layer and it's not working.Can anyone point a solution? Openlayers code: var wfs = new OpenLayers.Layer.Vector( "Stavros Features", ...
3
votes
1answer
186 views

Overlay Analysis in QGIS (or Preferably Python)

I would like to perform an overlay analysis in Python or QGIS to output a list of each shapefile that falls within certain boundaries. I have unsuccessfully tried to use the Spatial Join, Intersect, ...
1
vote
1answer
285 views

kml/kmz files not loading by google maps anymore

Until a few months ago this worked: https://maps.google.com/maps?q=http://www.jcea.es/pics/italia2015/italia2015.kmz It is NOT working anymore. I know that I can login in Google maps, create a ...
1
vote
0answers
83 views

how to use arcGIS to calculate the Conversion Probability certain land use to other land use?

I am doing dissertation about [predicting future urban expansion for Shannon River Basin In Ireland using Cellular Automata model and arcGIS] so at this stage I would like to calculation the ...
1
vote
3answers
310 views

Creating a new raster layer based on mean of other raster layers, ignoring NA values in R

I am trying to create a new raster layer that is made up of the mean values from 7 other raster layers. I get results using overlay function mean: mean <- overlay(2000, 2001, 2002, 2003, 2004, ...
1
vote
0answers
131 views

Using R to find attributes of spatial neighbors, especially with big spatial polygon data frames

If it's not too much, I have a specific question that leads to a more general one: I'd love thoughts on both if it's possible. First, the specific: I have an analysis involving census blocks and ...
1
vote
0answers
51 views

Shaded KML overlays on OSM tiles in QGIS?

This seems simple - but the solution is escaping me. I have a series of dynamically generated KML files describing simple, shaded polygons, with each polygon having a slightly different (externally ...
3
votes
1answer
52 views

How do I edit multiple features at one time?

In my case, there are about 30 overlaid features. How do I select all and edit them at one time? I want to reshape the features, mainly using the node tool to reshape a straight line into a (fake) ...
1
vote
1answer
91 views

Compare two rasters in R with the cell value from one replacing the cell value from another

I am trying to create a single raster from two rasters. The first raster is made up of all 0 values and the second is made up of the current date value (formatted in days from 001 to 365). The problem ...
1
vote
1answer
707 views

Compare two rasters with raster overlay and replace cell value with variable

I want to compare 2 rasters and when there is a change from 2 to 1 create a new raster that replaces the cell where the change has been detected with the change variable. ## Finds Cells that have ...
0
votes
1answer
52 views

Copying the visual shapes from another layer to the current one, while keeping the current layers' database

There are 2 layers that have similar shapes but small differences. I want to keep the shape of layer 1 while having the data of layer 2, which includes more data and it will be animated using ...
0
votes
1answer
168 views

Using spatial join in ArcGIS for Desktop?

I have two spatial layers of about the same (not exactly same) spatial extent. Layer#1 has about twice the number of polygons than layer#2 (in thousands). I am trying to calculate values for Field#X ...
1
vote
1answer
77 views

OpenLayers3 get feature request for more than one point in the same place

I created a map that brings up a popup overlay on click, the JSFiddle is here. The only issue I have now is if I have two points in the same location it. As you can see with the Birmingham point, ...
1
vote
1answer
61 views

Combining Get Feature requests within OpenLayers3 Overlay

I have a map which currently shows one feature of a layer in an overlay popup when you click on it, as per this JSFiddle. As you can see, it currently displays the address within the overlay. I am ...
1
vote
1answer
85 views

Merging OpenLayers3 overlay with a get feature on click command that closes

I have this JSFiddle that is working fine on its own to select cities in the UK. I have then taken this OpenLayers3 example and put it into a JSFiddle. I am looking to combine the two so I have a ...
1
vote
1answer
513 views

Summarize polygon area using another polygon

I have a shapefile representing public/private lands in Montana. This is a multipart shapefile where I've simplified attributes so that #1==private and #0==public. Next I have a shapefile of ...
0
votes
1answer
34 views

Growing error from west to east when overlaying raster and shape

I am using a shape of Austria from gadm.org which I want to overlay with a netCDF file in R. As the netCDF has projected coordinates in EPSG:31287, I have reprojected the shape using FWtools and the ....
0
votes
1answer
62 views

Is there a way to overlay a remote kmz file in google maps

I have a kmz file and want to overlay it on google maps. What I'm searching for is sth. like: https://www.google.de/maps?kmz=server/tour.kmz I've already checked the query params for google maps, but ...
0
votes
2answers
43 views

Generate a single shapefile from various intersection agreements

I have five vector files wherein I want to determine the spatial agreements among them using intersect. Here is my illustration. (Actually these are forest shapefiles from five different forest maps.) ...
0
votes
1answer
95 views

Weighted Overlay final raster to indicate inputs

I have a weighted overlay that identifies the most important areas in a corridor scaled from 0 - 100. I would like to be able to click on a cell and be able to identify which input rasters contributed ...
1
vote
1answer
86 views

Weighted Overlay Decimal Values for Evaluation Scale

I would like to do a weighted overlay of different raster datasets. I would like my evaluation scale to be from 1 to 10 with 0.1 as the incremental value. This way for example a criteria could have ...
1
vote
1answer
93 views

Calculating area of residential area wihin multiple ring buffer in ArcMap?

I need to calculate the size of residential area within 0-250m, 250-500m and 500-750m of a bus stop. I have made a multiple ring buffer around the bus stops. And I have a shapefile of the residential ...
1
vote
1answer
128 views

Projection bug between overlay and base layers

I am making a WebGIS application for a course and I am trying to integrate some nice base layers like OMS, Stamen, and Bing Maps with my overlay layers that are for Bolivia from a Bolivian map ...
4
votes
2answers
1k views

Overlay Vector Layer on Raster Layer

How can I overlay a Vector Layer on a Raster Layer and assign NoData Values on the Raster where the Vector Layer does not cover the Raster Layer? (preferable with ArcGIS)