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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29 views

DotSpatial Opposite of Featureset.Intersection

DotSpatial 1.8: I have some code to give me the intersection of my trip polyline and where it crosses key polygon regions. That works well: Dim fsResults As IFeatureSet = ...
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1answer
20 views

Tile server overlay in Google Earth?

I have recently become aware of a number of tile-server map sources and I would like to use these as overlays in Google Earth. Is there a way to do this directly that does not involve pre-downloading ...
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1answer
24 views

Leaflet Basemap and Overlay Display

When running this why does the open street layer not show up as the base layer by default? and why does the precipitation layer come up as already checked to display? None of the other overlays ...
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1answer
32 views

How to delete overlay within the same feature class?

So, the following scenario: I have plenty of polygons that are within another polygon, all in the same feature class. All of the polygons (the one overlaping the other ones as well as the ones being ...
2
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1answer
20 views

How to display data at diffrent depths in ArcScene

I am looking for a way to display data at different depths in ArcScene. I have a bathymetry layer which displays fine, and I want to overlay oil platforms in 3D over the bathymetry to show where ...
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1answer
19 views

In ArcGIS Modelbuilder: Mean value of different polygons within a buffered zone, weighted by area percentage

I am creating a model in ArcGIS model builder (10.2). I have buffered zones (polygons) and within these zones there are different soil types (polygons; Shapefile feature class). I have assigned values ...
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0answers
15 views

Overlay tools failure in ArcGIS 9.3 [duplicate]

I consistently get various error messages almost everytime I try to use an overlay tool (e.g. union, intersect, clip, spatial join) or in one case with spatial join I got none-sense results. Some ...
3
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1answer
51 views

Polygon made by colour difference

I need to analyze differences (historical) in coverage of some species (seagrass Posidonia). Although its a marine species, subject area is very shallow and even from common satellite and aerial ...
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1answer
74 views

How to add OpenSeaMap tiles as an overlay on top of osm base map with Leaflet?

After generating the OpenSeaMap tiles, I tried to add them as an overlay upon the openstreet basemap. The idea is after generating the OpenSeaMap tiles to serve them as "static" tiles to the client, ...
4
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1answer
25 views

Defining city name by using KMZ files

We have KMZ files of different satellite images. We want to check which cities these satellite images belong to. Is there a way to do it automaticly? Like a tool in ArcGIS or QGIS or whatever?
2
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1answer
52 views

Aggregating up spatial information

At present I have a dataset which is broken down by Electoral Divisions (circa 3,500). However, due to issues with some of my variables I need to choose a larger spatial unit - Local Electoral Area ...
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0answers
21 views

google earth - viewing KML file in world map

I"m using google earth and a KML file that I have generated. I would like to display all the KML points in a world map. Google maps online does it but the print is poor. Need a 300 dpi print which ...
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1answer
22 views

v.overlay in GRASS

As I understand, v.overlay module can be used for polygons overlapping processes. Polygon clipping, union processes can be done. There are many algorithms for these operations. Which algorithm is ...
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0answers
35 views

Georeferenced Image Overlay and export to new image

I have two Geotiffs (one satellite image, one clipped image). I want to put the clipped image over the satellite image, because it shows flow velocity from this shown glacier (see image below). I ...
2
votes
1answer
45 views

PostGIS function ST_SymDifference between two segment groups produces unexpected results

I try to calculate the symmetric difference for a set of segment groups A and B with precision of 1E-5 (ST_SnapedToGrid(geom,1E-5). I've formulated the an ideal test case for a H based shape segment ...
1
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1answer
20 views

Counting points on a line or polygon using join: number of points are calculated incorrectly [closed]

I am attempting to count the number of stream crossings within approx. 100m segments of a trail. I used this article to get quite close with join: ...
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0answers
25 views

Can I overlay a CartoDB visualisation on Bing Maps base?

If I am using Bing Maps as my base map, can i overlay a CartoDB visualisation (that I created earlier) on top of it? If so how do I go about doing that? The example on the cartodb site only refers to ...
5
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2answers
100 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 ...
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1answer
59 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 ...
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1answer
62 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 ...
1
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0answers
34 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?
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0answers
33 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
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1answer
60 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 ...
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1answer
46 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
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1answer
32 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 : ...
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0answers
57 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
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2answers
65 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 ...
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2answers
51 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
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1answer
96 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 ...
3
votes
1answer
63 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: ...
1
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1answer
14 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 ...
2
votes
1answer
31 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 ...
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0answers
41 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 ...
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0answers
41 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 ...
6
votes
1answer
182 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 ...
3
votes
1answer
157 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 ...
1
vote
1answer
212 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
139 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
199 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
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0answers
47 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 ...
3
votes
1answer
151 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
196 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
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0answers
73 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
186 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
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0answers
104 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
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0answers
47 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
77 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
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1answer
499 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
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1answer
51 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 ...