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

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16 views

Retrieve MapBox tiles in vector format rather than raster

I am using MapBox and I would like to render my tiles directly from vector format but I was not able to find how to retrieve the tiles in vector format rather than bitmap. So, when I use this url: ...
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14 views

Is QGIS Server working like this?

On CentOS 7 I have QGIS Server and QGIS Desktop installed. In QGIS Desktop I created a project with raster and vector data and saved it in a ".qgs" file. Then I copied the file in ...
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7 views

Sky View Factor of building roofs => Vector algorithm [duplicate]

I'm currently working on a project in which I'm trying to assess the SkyViewFactor of a given roof using building vector data. I've already managed to build a process based on vector rasterization ...
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1answer
42 views

QGIS Vector Data with blank attribute tables

I have vector data shapefiles for Manitoba, but there is no names in the attribute tables. It seems Manitoba is still working on their attribute data. Is there a shapefile I can download to get these ...
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1answer
16 views

Intersection of two vector tables data in postgresql

I have satellite raster data is converted in to pixels using create table gtru_tile_pix as SELECT (ST_PixelAsPolygons(rast)).val, (ST_PixelAsPolygons(rast)).geom FROM ...
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57 views

How to tell if map service is fully vector or raster?

sorry if this is a duplicate, but I was wondering how to tell if a map service (in web browser) is vector based or raster based? What I think to understood so far is that Google Maps for example is ...
4
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1answer
92 views

Creating shapefiles using textfiles in QGIS

I have a shapefile in QGIS which has polygons in it . There are several other attributes for each feature . I want to add another attribute to each feature . The value for this attribute is available ...
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24 views

How to buffer (flat) line segments? [closed]

I'm trying to buffer lines (splitted by vertices). The result I get with the v.buffer.distance ist almost that what I want to have. But in the end I get one polygon which is not splittet like the line ...
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2answers
38 views

Layered world map

First off I just want to say that I am NOT sure if this is the correct place to ask this question; So if it is not, please direct me to the correct exchange. So for the question: I am looking for a ...
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26 views

Aggregate/merge data upon insert into PostGIS (via gdal)

I am working on a project where I take a large raster file (1.5GB+), put it through a number of image-processing operations, and finally convert it to vector data. Being that the raster is large, I am ...
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6 views

How to make coincident a vector layer and a bitmap constructed from Google map tiles using programming

I can make a bitmap file from tiles that I receive from Google map using X_Tile,Y_Tile and Google map zoom parameters successfully.First I use a vector layer to find map extent in UTM,so I have ...
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2answers
12 views

Building error with QgsVectorFileWriter

I am working with qgis api c++ 2.8.2, in c++/QT 4.5 I try to save my List of QgsField but I have the error message : no matching for call to 'QgsVectorFileWriter' I took the sample from here : ...
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13 views

Problem with VectorLayer created in memory

I am working in c++/QT whithnthe qgis API c++ I had to build a personnalized vectorlayout called "TRACKS" , so i write a function that create in memory the vectorlayer like this : QgsVectorLayer ...
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1answer
18 views

Mapping continuous vector data on a continuous colour gradient in ArcMAP 10

I'm plotting vector data for different attributes for countries across Europe. I've used symbology to plot categories of countries. However, the data are numbers so are on a continuous scale. I would ...
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3answers
53 views

Generate line from unordered set of points

What is the best method to take a set of points and generate a line? There are too many to simply guess a "connect-the-dots" situation & These points do not have an attributes in which they can ...
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1answer
47 views

Is it possible to remove small transparent outline effects between polygons?

after using the vectorizing tool I get the following result (picture). Around the cells you can see a small "boundary". This thin line is transparent and annoying. Is it possible to remove these small ...
1
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1answer
17 views

How to force GeoServer to remove, or change, NoData Value from GeoTiff?

I am trying to display vector data of state borders, downloaded from GeoServer as GeoTiff, in QGIS. By default downloaded raster looks like this: After disabling NoData value in ...
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25 views

Making raster from vector

Have you ever met with nan value in raster? Im making raster in qgis from vector (one point) and all I have got is nan value and black raster.
2
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1answer
34 views

How to create a new empty memory layer with fields scheme from other layer in QGIS?

Being a complete noob with python so far, I got inspired by this answer: http://gis.stackexchange.com/a/155988/8202 to dive into it a bit. When creating features in a new target layer from an ...
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18 views

Vector layers don't seem to be exhibited properly [duplicate]

I'm a veterinarian that uses qGIS for making basic outbreaks maps, and am trying to branch out and expand what I'm doing. When I first started using qGIS 3 years (I believe it was 1.7), ago, when I ...
1
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1answer
41 views

Identify nodes in GRASS

Apologies if this is a really basic question but I have been unable to sort this out: How do I identify nodes in GRASS? Specifically, I am running a Salesman analysis and get the following error ...
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0answers
61 views

How to create contours from an IDW raster

I'm new to QGIS and am trying to create vector contours from this IDW raster. I followed Ujaval Gandhi's "Interpolating Point Data" tutorial step by step but am not getting the same results for step ...
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1answer
79 views

How to get smooth contours from points or IDW raster in QGIS

Hello I'm an artist trying different ways of drawing contours in QGIS using points with income values. I've been able to import a shp file with the data, create a layer with centroids of the census ...
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27 views

Creating a 3D model of airspace that I can interrogate to see if some other feature (like a tree) will intrude into the airspace

The goal is to create a 3D model of imaginary planes in space that I can interrogate to see where other objects in the vicinity of the model cut through any part of that plane. For example, an ...
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33 views

How to run Mapbox Vector Tile Mini Server?

I am trying to make an offline map for the vector tiles that I've exported from Mapbox Studio (mbtiles). I found this : https://github.com/BergWerkGIS/mini-server I have it downloaded on my ...
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2answers
35 views

How to measure the sum of the areas of each class in QGIS?

The project has a layer with several groups of polygons with different weights. Each group is associated to a weight. How can I get the sum of the area of each group?
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1answer
33 views

QGIS Convert bathymetry shapefile from fillable to strokeable

In Java I would like to stroke the bathymetry depth lines instead of filling the area. I'm starting with the Natural Earth Bathymetric Data: ...
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29 views

How to convert GeoPDF to ArcGIS with annotations (arcmap original labels)?

I've got a GeoPDF file that contains vector and annotation data (arcmap labels). I need to convert it into a feature class. I've tried to follow the former questions that been asked here: Adding ...
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0answers
42 views

Turning “normal” Vector Data into a GIS

I have a map in Adobe Illustrator with several vector layers. ( Therefore the vector data have no spatial reference and no attributes. What is the best way to turn these vector data into a GIS and ...
2
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1answer
32 views

Multiple display of vector layer in a qgis plugin interface

def initGui(self): """Create the menu entries and toolbar icons inside the QGIS GUI.""" icon_path = ':/plugins/cropEt/icon.png' self.add_action( icon_path, ...
2
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1answer
38 views

how can I get the majority (dominant) class of a raster to an area (polygon) using qgis?

I have a vector layer with many basic units of planning (zones), a raster layer with three classes of geology and other raster layer of geomorphology with five classes. How can I update the ...
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2answers
75 views

Add overlapping polygons

I have a feature class that contain many overlapping polygons. Each polygon has a field value which I would like to add together wherever the polygons overlap. There are about 100 polygons each with ...
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1answer
40 views

How to plot a shapefile with colors according to a column numbers in R?

reclass = function(x){ ifelse(x == 0, 10, ifelse(x > 0 & x <= 20, 0, NA)) } arch$ranks<-as.factor(unlist(lapply(arch$ranks,reclass)) arch.col = topo.colors(nlevels(arch$ranks)) ...
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20 views

Problem with passing ranks to different buffers

This issue is really troublesome.i have a SpatialPointsDataFrame which refers to a city.I needed to perform a join with a dbf in order to attach the population column which i did thanks to a couple of ...
2
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1answer
57 views

How to join a dataframe with a dbf via a common column in R?

I have a SpatialPointsDataFrame with the data of a city and i want to join it with a dbf that contains the population via a common column that they have. How do i do that so the first one has the ...
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44 views

Converting a (WAsP) vector map to a raster map with GRASS GIS

i'm quite new to GIS and i need to convert roughness data which is available in a vector format to a raster format. The final data should be on a simple 2-dimensional uniform grid with a constant grid ...
2
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1answer
94 views

How to plot certain values of a column in R?

Lets say we have a shapefile of cities with a column called category cities@data category A B A C A A B C How can i plot the A category only etc? Tried c<-cities$category[A] ...
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1answer
35 views

gdal_polygonize with World File

I have this image that I want to convert it to GeoJSON. And I have this World File: 0.0388048118 0.0 0.0 -0.0387897595 697054.11331 4458020.56656 When I try to run the gdal_polygonize command ...
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0answers
26 views

How to create displacement vectors in QGIS using GPS points with different dates?

Is there a way to calculate and visualize displacement vectors in QGIS ? I have DGPS points taken at the same place (ground control points), but their position moved over time as they are located on a ...
1
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1answer
30 views

Clip & save layer using OpenLayers 2

I ma currently developing a web mapping app. How do I make it possible for my app to clip and save area of interests or area I am working on. I can create a vector layer, modify it and delete if I ...
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35 views

Showing/displaying relationship between Earthquakes and Fracking operations?

I am presently analysing the relationship between hydraulic fracture operations and possible associated induced seismicity. I have both the earthquake data (as a shapefile with lat, long, magnitude ...
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1answer
337 views

Add feature manually to a vector layer in ol3

I'm trying to add a layer manually to a vector layer with javascript. I can't seem to determine why this is failing: http://jsfiddle.net/Kieveli/f4t6n6v1/4/ I've tried sane coordinates like 16,22, ...
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1answer
32 views

ArcMap 3D profile graph gives a level line

ArcMap's Profile Graph in 3D analyst works great for drawing a line on the map and seeing the profile. I am doing this part easily; single segments, multiple segments it works fine. However, it is ...
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1answer
50 views

How to measure the distance between multiple points and multiple polygons?

I'm trying to find a quick and accuarate way to measure the distance between 3 survey sites and all the designated sites within 10km. The survey sites are on a point vector layer and the designated ...
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0answers
42 views

PyQgis - Adding attributes to a POSTGIS layer

After reading @underdark's answer to this question on creating a new vector layer and @Matthias Kuhn's to this one on field calculation, I wrote a script that allows me to calcultate the mean ...
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0answers
46 views

NDVI from raster to vector isnt working

I have question...can I make from raster img. vector file via qgis? Because Ive tried it on NDVI image and Ive only got one file with atribut table full of #null. Image is from landsat7... ...
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1answer
94 views

ArcGIS, How do I get smoother contours?

I am trying to get nice smooth contours using ArcGIS. I have already smoothed out the DEM using focal statistics, simplified and smoothed the contours. The current result looks like this, which is way ...
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0answers
19 views

Plugin SWAP vector direction doesn't work in QGIS

I've installed plugin Swap vector direction in QGIS. But it doesn't work. I click and nothing. I need to flip lines (22 000 000 lines). In ArcGIS takes many hours and still flipping. I thought ...
1
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1answer
28 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
44 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 ...