A coordinate-based data model that represents geographic features as points, lines, and polygons.

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1answer
56 views

Render or display only the boundary of a vector layer containing thousands of polygons

This might be a very basic question but my lack of experience makes it really hard to answer. To have a cleaner map to print I want to display only the boundary of a layer composed of more than ...
1
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1answer
153 views

QGIS - some edit feature options disabled in vector layer [closed]

I created a new vector layer in QGIS, saving as I went along and then I saved the project and logged out. When I went back into the project, I wanted to add some more features to the same layer, so ...
1
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2answers
156 views

Configure default styles in LeafletJS

I want to change the default styles for vector layers in my Leaflet version 0.7.3. I can't find anything about that in in the documentation, so I made this hack: map.on('layeradd', function(e){ if(...
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1answer
119 views

Automatically changing the angle of a symbol in QGIS?

I am working with an iron age cemetery in QGIS. I marked every grave in a point layer with several columns; amongst others, burial rite (inhumation, cremation etc.). I inserted a second column for the ...
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1answer
122 views

Make diagonal grid in QGIS, divide square into squares

I have square polygon which is aligned under some degree and I want to divide this square to, for example, 25 smaller squares, which must be under the same degree in this square polygon. How this can ...
1
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2answers
331 views

Is it possible to not show node in editing mod QGIS

I actually have a plugin that allows me to draw on a vector layer (I made it based on the FreeHand Editing Plugin). When a mouseMoveEvent is detected, it creates a new point on the vector layer and ...
0
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1answer
118 views

Simultaneous multiple vector layer intersection algorithm

Is there an algorithm, you can suggest or recommend, that I can implement to intersect multiple vector layers? I have a few hundred layers I want to intersect and thinking of developing a little QGIS ...
2
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0answers
125 views

How to make a model with more than 2 input layers for buffering and merging?

Would it be possible to add more inputs to Buffer and Merge? From what I can see there is a limit of two input layers per both. As far as I know this is possible in ArcGIS's Model Builder but from the ...
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1answer
224 views

Vector Click Event is not working

Actually I figured out some problems and corrected it. I declared the overlay just outside the init function. So now I got the 'featureselected' event working properly. But 'featureunselected' event ...
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1answer
75 views

Land cover modifications in different time periods

I have several shapefiles which contain buildings built in different periods from 1948 to 2013. My question is how could I see which buildings for example in were built 1948 but are missing in later ...
1
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1answer
126 views

Country border between two points

I am trying to extract country borders between two points, using Python. The border is a Shapely Polygon.exterior or LinearRing, the start and end points are Shapely Points. My idea is the following: ...
0
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1answer
63 views

joining non-spatial pollution model (csv file) to Qgis

I need help..I have csv file with concentration data but without coordinates. Start of pollution concentration connect with that one point on map. Is there any chance ? Start of pollution ...
4
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3answers
836 views

3d vector and geometry operations in open-source GIS

There is some really good open-source software available to work with 2D vectors. For example QGIS has operations like buffer / clip / dissolve / select by location / join attributes by location... ...
3
votes
1answer
177 views

Is the QGIS “Random selection within subset” selecting spatially random or randomly from the attribute table?

I am trying to figure out exactly what is being randomly selected. I have a layer of road segments and I would like it to select a road segment at random within a neighborhood (the subset). This would ...
4
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1answer
2k views

Sketch event in Openlayers 3 drawing interaction

For drawing Polygon in OpenLayers 2 we could use as follow: function drawEnd(){ ... } function putPoint(){ ... } function sketchModified(){ ... } function cancel(){ ... } var ...
1
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1answer
35 views

Not all polygons removed when cutting from vector layer in QGIS

I have created ten polygons representing lakes on a vector layer, and I am trying to cut them from an imported and re-projected vector layer of administrative districts. When I use the 'Cut with ...
2
votes
1answer
296 views

Vector tiles in ArcGIS

I have a vector map (consisting of several polygons) and I would like to create several overlapping tiles. I did the same for a raster map using "split raster". For the vector map, I created an ...
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2answers
95 views

How to deactivate the Color Ramp in QGIS graduated vector styling?

I want to display points with different size and I DO NOT want to have a color ramp. Do you know how I can do that?
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1answer
197 views

How to get a “clean” polygon after using dissolve in QGIS?

I'm trying to obtain the boundaries of shapefile, thus to clean the inside as a matter of speaking. While I had expected that dissolve while get me a proper polygon, unfortunately it still has some ...
2
votes
1answer
487 views

OpenLayers 3.5.0, clear highlighted feature after removing feature from source

I want the user to be able to delete the highlighted feature. This works well, but the feature is not cleared until I move the pointer outside the feature geometry. I am using the OL 3.5.0 library. ...
4
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4answers
1k views

Checking if polygon fits inside another polygon using ArcGIS or QGIS?

How do I check if one polygon fits inside another polygon? Furthermore how do I automatically check if one polygon fits in other polygons of my shapefile? I have a shapefile with thousands of ...
0
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1answer
1k views

Adding in multiple layers in OpenLayers 3

I am trying to add in the following two layers into my OpenLayers 3 map. The issue i'm having is that whichever one is written in last is the only one that is showing. I imagine there is a way to ...
0
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0answers
119 views

Splitting lines table using point table in PostGIS

My problem is that I want to get the shortest route between multiple point pairs which are stored in a table (PostGIS). In PostGIS I also have a network created using pgr_createTopology on a table ...
2
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1answer
89 views

How to set feature vertex Z from an intersecting feature's Z?

In ArcGIS how can I set the Z values of the portion of a line that intersects another line to the Z values from the other line? A batch process is preferred. I tried FeatureToLine, but the null ...
2
votes
1answer
62 views

Extracting area from DEM Raster?

After applying constraints to the DEM I polygonised the raster (using GRASS r.to.vect.area) The result is shown below with a lot of vector with resolution = [30 * 30] Is there any solution to make ...
2
votes
1answer
123 views

Feature is a point or polygon

Im new to GIS and am just curious if there is an instance where a feature can be a point in one map and a polygon in another map and vice versa?
1
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1answer
142 views

How to use QGIS field calculator between different points of same layer?

I'm in a course learning about GIS systems, and we have recently recorded a gps track. I've exported this track as .gpx and imported the points into QGIS. Each point has a timestamp. One of the ...
0
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1answer
57 views

Openlayers cluster stragegy total count

How can I get total feature count of vector layer: var mylayer = new OpenLayers.Layer.Vector(null, { "protocol": myWFSProtocol, "styleMap": style, "strategies": [ ...
0
votes
1answer
55 views

Make OpenLayers filter initially empty

I have an openlayers vector layer that loads data form service. But it loads all data initially. var mylayer = new OpenLayers.Layer.Vector(null, { "protocol": myWFSProtocol, ...
0
votes
0answers
68 views

Snapping to a grid does not work

I have two shapefiles that were created in GME using the generate vector grid. They both have the same projection NAD 83 Transverse Mercator. The grid size is 5000m. The grids overlap in that they ...
0
votes
1answer
69 views

Merging SHP lines with attribute data combined?

I have one shapefile which contains hiking routes and another shapefile which has ski routes. Sometimes they follow the exact same path. In QGIS if the lines mentioned above are in the same SHP I ...
2
votes
2answers
110 views

QGIS modeler - how to extract polygons by multiple arguments?

I'm using QGIS modeler to extract lines by not one, but multiple attributes. For example, I have a road network, and I want to extract only road with character values in field TYPE: value_one and ...
5
votes
1answer
105 views

Which system of units does the unit 'degree' belong to?

Let us say that I would like to store latitudes and longitudes like this: lat 35 degree long 80 degree Which system of units does the unit 'degree' belong to? It is not really a SI unit nor a ...
0
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2answers
481 views

Latest shapefiles of Indian states

I need shapefiles of Indian states that of 2011 which has almost 671 districts of India. Can anyone please help me?
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0answers
74 views

Why does the transformation bring bad results?

I have this map which has a polygon drawn on it. For the background map I use a WMS via ol.source.TileWMS and the polygon uses a ol.source.Vector object. Normally my view projection is EPSG:31467 but ...
2
votes
0answers
109 views

QGIS's “Points in Polygon” counts zero in every census tract

I am mapping the location of incidents of asthma using QGIS. I would like to count how many points are in census tracts to better understand the areas where asthma occurs most frequently. My map ...
5
votes
2answers
361 views

Calculating average raster to point distances within census tracts

I have some experience using ArcGIS, but mostly with the field calculator in the attribute table/spatial joins, so I apologize if I say something that doesn't make sense. To provide a bit of ...
1
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2answers
78 views

Selecting/Exporting points from one layer that do not overlap with the points from another layer in Qgis

I am working with QGIS and have the following problem to solve: I have 2 point layers. Layer 1 has more points than Layer 2 but all points of Layer 2 have the same position as Layer 1. I need to find ...
0
votes
1answer
163 views

QGIS: Delete information from rasters and shapes that are out of country borders [duplicate]

I am trying to make topographic maps for some countries and show only those countries. I already created reliefs from SRTM-data and imported lake and river data from Natural Earth. Now I want to ...
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votes
1answer
78 views

Why don't shapefiles online contain the coastline (country borders)?

I have searched everywhere and Geofabric has the best packages of shps yet doesn't have the coastline of countries. I'm talking about the line that demarcates a country i suppose they are called ...
1
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1answer
233 views

Georeferencing/Spatial Adjusting of vector river dataset to DEM in ArcGIS

I have a huge dataset of vector river data (over 10'000 rivers) which are saved in a shapefile and were initially derived from a topographic map. However when comparing this vector to DEM data (SRTM ...
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0answers
51 views

Select features intersecting a linestring in QGIS

I wrote a python plugin that grabs all (vector, linestring) features between two points on the map. At the moment, I select all features intersecting the rectangle around these two points, and then ...
1
vote
1answer
112 views

QGIS equivalent to MapInfo Sum Attributes for selected vector objects?

I´m looking for QGIS equivalent to the basic MapInfo tool "Sum Attributes". I´ll explain what it does: For selected objects in a vector layer, a popup window shows basic statistics such as: - Sum ...
0
votes
1answer
105 views

Adding features to a vectorlayer using checkbox

I'm trying to add features to a vector layer using a checkbox. var featureOverlay = new.ol.FeatureOverlay; $("input:checkbox").each(function(){ var $this = $(this); if($this.is(":checked"...
1
vote
1answer
76 views

Create Multiple Circle

I am trying to make many points in a map as a grid. The code makes what I expect but the time to load is quite long so I suppose that there should be other ways to be more efficient drawing many ...
0
votes
2answers
279 views

Exporting layers from ArcGIS into PostGIS while preserving attributes such as color

I have managed to import/convert a KML into ArcGIS 10.0 (ArcMap) using the built-in conversion tools and now have a series of layers. Next, I export these layers to a PostGIS database using the ...
3
votes
2answers
339 views

Can't export customer's shapefile to latitude and longitude

I'm very new to this application so bear with me. I hope that I am missing something very elementary. I have a shapefile supplied by my customer. I need to get the latitude and longitude for each ...
2
votes
1answer
884 views

Openlayers 3 Circle Vectors Not Visible

I have two coordinates which are projected in EPSG: 3857 coord1 = [-10399758.486973494, 5604341.818491254] coord2 = [-10402629.416641055, 5593700.936383396] I'm trying to get them to appear, ...
3
votes
1answer
450 views

Representing overlapping polylines in QGIS

I have several shapefiles representing bus lines with different colors for each segment, however, because the lines are exactly superposed, only the shapefile on top can be seen. Is there a way to ...
1
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0answers
211 views

Merge multiple geojson-polygons

Lets say I have a very big image With a polygon in it: I want to polygonize this very big image with gdal polygonize. But the image is too big, so I dont have enough memory to polygonize that ...