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

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0
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61 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 ...
0
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0answers
79 views

Los Angeles public parking lot polygons?

So, I'm looking for some relevant data to incorporate into my map, and one of them is public parking polygons. Is there such a .shp file with these data?
4
votes
1answer
82 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 ...
3
votes
2answers
749 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)
7
votes
3answers
639 views

How to get a list of adjacent lots to a road in ArcMAP and PostGIS/QGIS?

In the following map, I have: A line / road layer A parcel / lot layer The Task: Find and count the list of lots adjacent to the road with their types (parcel_type is a field in the parcel ...
2
votes
1answer
86 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
vote
2answers
526 views

CartoDB map in openlayers

Is there a way that i can upload my CartoDB map in Openlayers as a WMS layer or Vector layer. Here is the my CartoDB map link. http://cdb.io/1nxdrpf
1
vote
1answer
76 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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2answers
74 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 ...
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0answers
30 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
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1answer
29 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
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1answer
27 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, ...
1
vote
2answers
3k views

Convert vector data with irregular points (no grid) to raster with QGIS?

I am aware that how to convert a vector layer to a raster layer is a quite frequent problem and that there are many questions and answers dealing with it. However, none was helpful concerning my ...
0
votes
1answer
42 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 ...
0
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0answers
48 views

3D building data for London

Any tips on where I can find 3D building data for UK/London, preferably LOD2 (Including roof structures)? I am aware of the Virtual London dataset but I would like a more recent one.
1
vote
2answers
48 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 ...
0
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0answers
25 views

Selecting polygons using another polygon? [duplicate]

Hi, How is the best way or fastest(if there is) of selecting polygons of a different shapefile using a polygon of another shapefile. exercise example: i want select all the light brown polygons ...
0
votes
1answer
83 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?
1
vote
0answers
63 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
63 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 ...
4
votes
2answers
151 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
vote
3answers
2k views

Where is the QGIS Parallel Line Plugin?

Somehow I believe to recall there does exist some ind of "draw paralel line" plugin for QGIS. Could anyone please point me to - I cant find it :-/
3
votes
1answer
982 views

Splitting lines at a specified distance

Does exist some plugin with it is possible to Splitting lines at a specified distance in Qgis?
1
vote
2answers
33 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
42 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 ...
-2
votes
1answer
63 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
vote
1answer
98 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 ...
3
votes
4answers
9k views

Calculating the minimum distance between points and polygons in QGIS

I have two vector layers: one point and one polygon and I want to calculate the minimum distance of each point from the polygons (ie the distance from the closest point of the closest polygon). Is ...
1
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0answers
29 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 ...
0
votes
1answer
76 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); ...
1
vote
1answer
60 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 ...
1
vote
1answer
50 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 ...
3
votes
2answers
130 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 ...
3
votes
1answer
155 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 ...
4
votes
4answers
8k views

Looking for an annotated vectorial map of the world

I'm looking for an annotated vectorial (PS/SVG/...) map of the world (+countries). Wikipedia contains many vectorial maps (e.g: http://commons.wikimedia.org/wiki/Category:Blank_SVG_maps_of_the_world ...
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0answers
31 views

QGIS - save vector poly layer into individual shp files? [duplicate]

Using QGIS v2.8.1, I have a directory of GeoTiff images. Using the raster ‘Tile Index’ plug-in (selecting “location” as the file index), I am able to create perfectly matched vector polys that I can ...
1
vote
0answers
117 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 ...
0
votes
1answer
40 views

Fill larger polygon empty space with closest subset of polygons

Looking for an ArcGIS or QGIS solution. I need to divide up the space of the large single green polygon. Each new polygon would represent "nearness" to the purple polygons and have the ID of the ...
4
votes
3answers
896 views

Vector Mapping for iOS?

Are there any vector map data providers with API's, that i can use to build my app on iOS natively (not on a webview). Specifically im looking for: For a library/framework that uses existing map ...
1
vote
2answers
88 views

Where do I get Elevation Data for Scotland?

So I am new here and I arrived here because I have been searching for quality elevation data for the entire Scotland but I have not succeeded yet. Kindly help if you know where to get the data Raster ...
1
vote
1answer
21 views

Previewing data type of vector layers in QGIS Browser?

One of the features I really like about ArcGIS is that in the Catalog pane, it will show you what vector data type (whether it be point, line, or polygon) a layer is in the little icon, which is quite ...
1
vote
0answers
59 views

Does interpolation create a vector or raster?

I have been reading about interpolation and am trying to understand whether interpolation results in a vector or raster. Say I have a layer of points and I am interested in creating a raster that fits ...
1
vote
2answers
173 views

Clip tool does not work Qgis [closed]

Is there any particular reason why I cannot clip in QGIS (2.8)? I have a Vectorgrid which I created based on another shape - namely a country. Now I want to clip the vectorgrid to the size of the ...
2
votes
1answer
291 views

“Node tool: could not snap to a segment on the current layer” message

I have a strange issue. Editing a layer with node tool I get always the following message: "Node tool: could not snap to a segment on the current layer." This error happens to me even with a fresh ...
0
votes
1answer
27 views

How to turn a vectorgraph into raster correctly?

In QGIS2.8 version, I added several points in a point vectorgraph. When using the grid - > Conversion - > rasterized vector , The results turn out into a black figure. How to turn a vectorgraph into ...
0
votes
1answer
114 views

QGIS 2.8 Convert a vector to a raster layer

When I change a vector layer to raster using raster button->converse->Vector rasterization in QGIS2.8. I get only a black picture. Why is that so and how can I convert a vector layer to a raster ...
11
votes
5answers
8k views

Libraries to render vector-based maps in the browser

Is there a open source JavaScript library like leaflet or openlayer which can be used in a web or mobile application and loads vector-based maps instead of images? I only need the road information and ...
5
votes
2answers
381 views

WFS to Vector Tiles

Is there, by some miracle, an existing piece of software which is able to convert a (3rd party, GeoServer) WFS feed into vector tiles? In a utopian world, this would happen on the fly, but a ...
2
votes
1answer
84 views

How to suppress polygon boundaries shared by objects of same type in QGIS?

Given polygons - like landcover in OpenStreetMap or street areas in cadastre - how can one suppress those polygon boundaries which are shared by objects (features) of same type in QGIS (see figure ...
2
votes
1answer
138 views

How to reproject all the vector files in a folder to a particular projection using ogr2ogr?

We have a folder with all sorts of vector files like tab,shp,dxf. Many of the files are in different projection. I would like to convert all the files to EPSG: 4326 and eventually the non-shapefiles ...