QGIS is a cross-platform GIS application licensed under the GNU General Public License.

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1answer
15 views

Is there a way to create a presence/absence matrix of polygons per cell in a grid using qGIS?

I'm working in QGIS with species distribution polygons and I want to know how many cells in a grid does the polygon overlap. I've tried creating random points within the polygon and then used ...
3
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0answers
33 views

Modify CSV file in QGIS before joining it to a shapefile [duplicate]

I've imported a Delimited Text File that I want to join to a shapefile I have. Unfortunately, the join field has a pesky ' character before the actual string. I wanted to delete that character, but ...
1
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1answer
37 views

How to create a shapefile from xy in .csv file?

I find many difficult to create a new shapefile in a new project following those steps. I think the .csv file is correct (there are only: ID, X coord, Y coord) but when I would create the shapefile ...
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0answers
20 views

QGIS Modeler different results by calculate the $area [on hold]

When I use the graphic modeler,add a field and calculate the area, the sum of the area of all records is different to result which I get by calculation in the fieldcalculator. The result in the ...
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0answers
11 views

Calculate obstacle accountability area in QGIS

Still being new to the whole GIS world, I am trying to calculate a regulatory takeoff obstacle accountability area for a given runway. For my case, this is defined as an area as follows. At the start ...
4
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1answer
66 views

New field names after joining 2 tables in QGIS

When joining two files (A.csv and B.shp with a common unique ID) in QGIS the new fields in B.shp (from A.txt) include the name of the field + the name of the file where it comes from (A). For example ...
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1answer
32 views

snapping line nodes to points

I have a dataset of manholes and pipes; I want to snap the lines start and end nodes to the manholes if they are within a specified distance. Been trying to find away to do this using PostGIS or QGIS ...
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2answers
24 views

How to turn a point layer into classified proportional circles in QGIS 2.12?

I'm trying to style a point layer representing cities around the Mediterranean following these two rules : The points should be represented as proportional circles, following a classification in 5 ...
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0answers
8 views

Qgis slow on loading project

Is there any work around to mitigate the amount of time QGIS takes when loading projects that have large tables from postgis layers . I have tried to turn off this large layers so they are not in use ...
2
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2answers
198 views

QGIS How to label individual sides of polygon

Using native QGIS layer property definitions, I have successfully labelled each polygon in my layer with its area and perimeter. Never satisfied, I now wish to label each side of each polygon with ...
0
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1answer
32 views

Style file with QGIS

I created a very good symbol layout for a current map. I will be creating similar maps just different regions and want to keep the symbols and markers that way they are. The new data will have same ...
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0answers
13 views

QGIS How and where to save Vektorlayer for fastest access/performance

I am fairly new to working in Q-Gis in a local network, please tell me if I missed some information crucial to answering my question. I have a Vectorlayer containing 36000+ line Objects with a large ...
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6answers
627 views

How to export attribute table with start and end coordinates of lines to Excel?

I am working in QGIS. I have a georeferenced line layer and I want to export the attribute table and the coordinates of start and end points of my lines to Excel. Can I do this with QGIS?
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2answers
28 views

Changing point data coordinate system without moving points in QGIS?

I made a mistake regarding coordinate systems and lining up two layers. I have a raster with elevations in EPSG:2949. I created a point data shapefile and entered about 600 hundred points manually ...
1
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1answer
12 views

Raster update error when saving heatmap in QGIS

I am using QGIS and I recently added a delimited layer and all my coordinates appear fine , however when I add a heatmap I get the error "Raster update error: Could not open the created raster for ...
1
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1answer
28 views

QGIS: getting NULL values when using “Join Attributes by Location” of lines and polygons

I'm using QGIS 2.12.3-Lyon. I have a polygon layer (~130k square polygons with some small overlaps) and I have imported a road network from OpenStreetMap (via Geofabrik, ~141k road segments) for my ...
2
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0answers
43 views

Create a layer, edit and save. Where are my features?

I created a layer (e.g. point) in QGIS with QgsVectorLayer from memory: mem_layer = QgsVectorLayer("point?crs=epsg:32630&field=id:string","TempFile","memory") ...
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0answers
17 views

Qgis becomes unresponsive when adding layers

Qgis suddenly won't allow addition of vector layers when running on PC (Lyon 2.12.1). I've reinstalled it, no help. I've recently changed to Windows 10 from 7, otherwise nothing much has changed on ...
2
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1answer
23 views

QGIS Atlas pages with different raster base layers?

Is it possible to enable raster layers only for specific Atlas pages, without using multiple map Windows? Unfortunately, there is no way to set transparency of raster layers by an expression ...
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0answers
24 views

Get the same coordinates for points after downloading a .osm file

I downloaded a .kml file that contains bike stations which I know the coordinates (latitude and longitude). So I got a layer that contains points corresponding to the stations. Then I downloaded the ...
3
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1answer
34 views

Update column in .shp from .tab with QGIS

Is it possible to perform in QGIS an "update column" on a .shp table with data from a MapInfo.tab having one field apparently in common? One of the greatest uses of QGIS (for me) is the availability ...
7
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0answers
79 views
+50

Output formats for QGIS Heatmap plugin not appearing in drop-drown in Ubuntu

I've been trying to use the heatmap plugin on QGIS (2.8.2) on Ubuntu(14.04) but the drop down for the output formats doesn't get populated. Selecting the drop-down allows me to press OK on the plugin ...
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4answers
8k views

How to fix QGIS error “Entry Point could not be located”?

Today, after returning from vacations, I started my QGIS 1.7 and got this terrible message: Help, anyone?
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2answers
21 views

How to calculate area in sq m - troubleshooting projection issues in a global dataset in QGIS

I am using QGIS version 2.12.3. I have 3 polygon shapefiles: A, B and the intersect of A and B, which we can call C. All I want is to add a field to the attributes table of each shapefile giving ...
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0answers
12 views

Icon for plugins in own repository

Does anyone know if there is an opportunity to add icons for your own plug-in in its own repository? like this not like this with green puzzle I spied on how to implement it on the official ...
3
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1answer
240 views

Maximize clusters of points from coordinate data

So I am definitely new to the GIS world, so bear with me if I don't know the best way to articulate my problem. That said, I am ready to learn, I would definitely welcome any direction that you all ...
2
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1answer
28 views

Extracting zeros from numpy array and creating a new raster

The following code reads in several .tif files from an input folder, converts them to numpy arrays and adds them together. All input files are binary: inputFolder = "/home/usr/Desktop/BufferFolder/" ...
9
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3answers
5k views

Divide a complex shape file into a grid

I have a decently detailed shapefile with polygon/multipolygon features (the file is about 500mb). It's actually a shapefile of the entire world, with the features representing coastlines. I need to ...
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2answers
22 views

How can I handle NULL values in a color ramp? [duplicate]

I'm mapping areas in QGIS 2.12 based on average pricing, using area polygons (PostGIS) joined with a CSV data table that doesn't have values for areas that didn't have any sales. I'd like to color ...
3
votes
2answers
45 views

How to select the most populated neighbourhood of each town in the country using QGIS?

I have data from a national census with population for each neighbourhood, grouped by municipality and town, in the country. I want to select the most populated neighbourhood of each town (there's a ...
6
votes
2answers
537 views

How to symbolize features with NULL values in graduated symbology?

I have a polygon feature dataset, and an attribute from a different table that I join (one-to-one) within QGIS in order to symbolise the attributes as a choropleth map. However, not all polygon fields ...
2
votes
1answer
17 views

Multi-string data-set without z layer, applying ordinal values as a workaround

I'm new to GIS and have been learning a lot over the last few weeks, however, I've finally come to a point where I could use some help. I'm working with the pdx_streets data-set from ...
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3answers
5k views
+200

How to calculate Network Service Areas in QGIS?

Is there any way in QGIS to apply service area buffers e.g if I have a point on a map I wish to show the service coverage of 1 mile, 2 mile, 3 mile, breaks using the road network?
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1answer
23 views

Locating and adding state layers to a QGIS map.

If I wanted to add layers for a state (Indiana) in a program like QGIS so I could produce several maps (Infrastructure, Water Resources, Mineral Resources, and HAZMAT concerns), how would I locate and ...
1
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1answer
15 views

Error when using viewshed analyis plugin with merged shapefile

I am using Qgis 2.12Lyon and try to run a viewshed analysis to show the intervisibility between several points in more than one shapefile. I have a digital elevation model (.tif) which is projected ...
2
votes
1answer
22 views

Excel Tables as Labels or Annotations

I would like to take excel tables and place them in a label or annotation so that I no longer have to copy and paste them into the figure layout as picture objects. I know this isn't possible in ...
3
votes
1answer
40 views

How to create a fishnet/grid along a polyline or polygon

I am trying to generate a fishnet/grid along a line/polyline or polygon boundary in ArcGis 10.3 or QGIS. While it is totally intuitive and easy to generate a box-standard grid, what I am trying to do ...
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0answers
15 views

How to select within a distance using QGIS [duplicate]

With QGIS 2.12.3, I have two projected EPSG:2927 point shapefiles, A and B. I would like to create a selection of A points that are within 100 meters of any B point. This is easy in Arc, using the ...
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0answers
26 views

ST_Intersection between MultiPolygon tables leads to gaps, missing intersections

I am trying to intersect two MultiPolygon tables, which are in the same UTM projection, and calculate the area of their intersections. I am getting some surprising results when I examine the ...
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0answers
14 views

How to get a multi-attributes vector from an SRTM raster in QGIS?

I split an SRTM raster into 3 different raster files representing the altitude, the slope and the exposure, using QGIS DEM analysis tools. How can I output a single vector file with the 3 attributes ...
0
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0answers
7 views

QGIS Server - I can't update QGIS layers that don't have a geometry field via WFS

I am using some layers that are data only (no geometry field). These tables are related to other geometric layers, as you can see in the config below : When trying to publish in WFS these "no ...
0
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0answers
15 views

Looking for real examples of using GIS in logistics and transport systems (maritime, auto, rail) [on hold]

As mentioned in title I'm looking for real examples of using GIS in logistics and transport systems. To be specific I'm trying to find any articles or books with detailed explanation of achieved goal ...
0
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1answer
24 views

creating a transparent layer background in QGIS

I have created a heatmap in QGIS to cover my point data and I have saved it as geoTiff so that I can import into tilemill, which I managed to do but my background is black .In QGIS however I want ...
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1answer
15 views

QGIS Plugin 'make' error on Windows

Creating QGIS plugin via PluginBuilder and compiling resources via simple 'make' works straightforward under Linux (SuSe 13.2). Under Windows 'make' (3.81) produces an error: ...
0
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1answer
319 views

QGIS Server on Windows7 Step-by-step / Test wms by adding in QGIS?

I am trying to Test a WMS by adding in QGIS as per http://anitagraser.com/2012/04/06/qgis-server-on-windows7-step-by-step/ If I follow the steps, QGIS cannot find the server. When I take a look at ...
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0answers
24 views

Zonal statistics shifted

I am working with QGIS (newbie). I have a raster map with 0.5degrees resolution. I created a 0.5degrees width grid layer and I compute zonal statistics from the raster. My problem is that it seems to ...
2
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0answers
29 views

How to select a WMS layer style in QGIS

WMS standard allows specifying a list of styles for each WMS layer. The users can then use the style name in the URL query parameter "STYLES". If the styles are not specified, "default" is assumed. ...
2
votes
1answer
18 views

QGIS - Installation issue Windows 7 64 bit

I am currently trying to install QGIS but it has been on the same point of the installation for almost 30 minutes. I don't know if it is simply taking a long time to create a folder, but it seems as ...
1
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3answers
163 views

Creating network datasets from OSM data in QGIS?

I am having a difficulty to use network analysis in ArcGIS because of unavailable network datasets. So, I googled it and realized that it is possible by using OpenStreetMap. However I don't know how ...
0
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0answers
16 views

Reclassification of CORINE map using R

I am trying to reclassify the CORINE map for Hungary to 4 classes in R. but after reclassification, when I import the asc file to QGIS it loads it empty. Am I doing something wrong? ...