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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3
votes
2answers
37 views

TileStache Vector Tiles Overlay problem

I am using TileStache to serve my own vector tiles using a postgis datasource. First I re-projected the shapefiles I had using ArcMap ( reprojected to Web Mercator (Auxilary Sphere)) and loaded them ...
1
vote
1answer
181 views

CartoDB - Method to show/hide layers for hatching overlap for > 4 layers?

Our goal is to show/hide individual hatched maps. Unfortunately we have more than the 4 max layers allowed in a viz. We successfully made and example where we show/hide the 4 layers in a viz: ...
2
votes
1answer
330 views

OpenLayers3: How to show a KML layer with the export to png Button

so... I have this script: <script> //Script1: Script de criação do mapa. var map = new ol.Map({ layers: [ new ol.layer.Tile({ ...
1
vote
1answer
276 views

how can I make “weighted sum overlay analysis” in QGIS? Ordered Weighted Averaging manual may be useful

I have weighted raster data converted from polygons with different categories. I have ArcGIS with 3D Analyst extension, unfortunately do not have Spatial Analyst, and I would like to use QGIS to make ...
1
vote
1answer
395 views

Selecting raster data by location: for raster and feature class data

I have rasters covering certain spots in my environment, I'm looking for a way to extract the values which occur at locations which are defined by a selection of feature layers. I've tried with the ...
2
votes
4answers
1k views

Produce a list of polygons that a line crosses

I have a polyline feature class and a polygon feature class. What I want to do is add a field to the lines that lists all polygons that touch the line. This is effectively performing a ...
0
votes
1answer
34 views

compare three rasters and three conditions with overlay in r

I'm trying to run an overlay function with rasters where I want to meet all of 3 different conditions at each cell and produce a single raster as output. Running ifelse with the & operator ...
4
votes
1answer
284 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
68 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
790 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
33 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
357 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
0answers
23 views

Can MapboxGL use nearest neighbour interpolation for overlay image? [closed]

In HTML+CSS version of mapbox/leaflet I can set image-rendering option for .leaflet-image-layer with CSS to choose interpolation method. How can I make this in GL renderer?
1
vote
1answer
108 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
341 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
233 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
29 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
45 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 ...
8
votes
6answers
8k views

how to overlay a polygon over SpatialPointsDataFrame and preserving the SPDF data?

I have a SpatialPointsDataFrame with some additional data. I would like to extract those points inside a polygon and at the same time, preserve SPDF object and its corresponding data. So far I've ...
1
vote
1answer
41 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
25 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 : ...
1
vote
0answers
36 views

Leaflet.js setBounds, scaling

I'm using leaflet.js to create a map of Scotland, with two insets for the Orkney and Shetland groups of islands. This is as far as I've got. I wish to guarantte that no matter what size the overall ...
2
votes
2answers
59 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
40 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 ...
3
votes
1answer
42 views

Get tile layer intensity at given zoom and longitude/latitude (Leaflet)

I can display a tile layer as an overlay in Leaflet via an url of the form path/to/my/tile/layer/{z}/{x}/{y}.png : my_overlay = L.tileLayer('http://path/to/my/tile/layer/{z}/{x}/{y}.png', { maxZoom: ...
0
votes
1answer
55 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 ...
1
vote
1answer
13 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
108 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
29 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
182 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
35 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
160 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
40 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 ...
3
votes
1answer
117 views

Loop to check multiple polygons overlap in r

I have a set of polygons (available here: http://ulozto.cz/x39ELbFt/polygons-zip) created in QGis and processed in R. I would like to know if they are overlapping or not, and if yes, where is the ...
0
votes
1answer
117 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
107 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
119 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
43 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 ...
7
votes
1answer
6k 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
115 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
137 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
65 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
113 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
80 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
40 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
50 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) ...
0
votes
1answer
61 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 ...
0
votes
1answer
290 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
49 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
117 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 ...