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

learn more… | top users | synonyms

2
votes
2answers
60 views

Slope Analysis in QGIS

I am New to QGIS, I have the Contour Information in the form of Line Features, How can I do a Slope Analysis. Is it Possbile at all ? For Reference I am attaching the Image. the lines in the ...
1
vote
2answers
37 views

How to split a large point vector layer in QGIS?

I need to split my shapefiles into much smaller pieces so that I can upload them onto the Postgis server. Shapefiles have dbfs with 14gb (1,000,000 rows) and I need them to be under 2gb. I've tried ...
1
vote
1answer
34 views

Where to use the shp2pgsql commands?

I need to upload some very large tables (over 10Gb) into Postgis so I actually found this link What is the best hack for importing large datasets into PostGIS? The DB manager is far too slow and only ...
1
vote
0answers
6 views

Feature Labels wrong with GeoJSON data source

EDIT: I found out that the attribute table changes when zooming, my GeoJSON output does not change however. I am working on a QGIS project where I've imported points as a GeoJSON data source from a ...
0
votes
0answers
14 views

Unsupported Source

If I try to save a raster files from a WMS once saved tells me that the source is not supported, "Data Source not supported: /Users/beatriceluise/Desktop/wms/Senza titolo.tif is a raster data source ...
1
vote
3answers
51 views

Digitizing Tools error in QGIS

I receive this message: Digitizing Tools: Amend Line is disabled because layer CRS and project CRS do not match. If I set the CRS of the layer the same as the project CRS (W84 Pseudo Mercator) is ...
4
votes
1answer
2k views

Why are the Google basemaps no longer appearing in QGIS?

I had done a few projects using Google Physical/Streets as basemaps but now when I re-open those projects all layers appear except for the google basemap (other layers include .kml). I had ...
1
vote
1answer
37 views

Creating a polyline with a specified slope

I would like to create a road (polyline) starting from a point, with a specified slope, until reaching the top of a hill (or going out of the DTM Raster). The dowstream slope of the DTM must always ...
2
votes
3answers
84 views

Is there a way of labeling the number of points with the same coordinates?

After reading through the following question (which is kinda related but not quite what I need): How can I show points on the same coordinate as e.g. a bigger symbol in QGIS? I found out that there ...
1
vote
2answers
25 views

QGIS count how many lines cross a polygon

In QGIS I create some lines that cross three polygons. By using intersection, it will create a new shape file that gives me as a result the lines inside the three polygons. If I open the attribute of ...
1
vote
2answers
27 views

Backup GIS data on postgis database from pgadmin3

I am using a postgis database with qgis and managing it with pgadmin3 I have already investigated the backup/restore options within pgadmin 3 and done one test run on one database I am wondering if ...
1
vote
0answers
15 views

QGIS not loading default layer style from PostgreSQL database on startup

I have saved a vector layer style to my PostgreSQL database source. I then amended the layer_styles table record for the relevant layer by editing the styleqml field (just changed the outline_width ...
1
vote
1answer
33 views

QGIS line cross a polygon

In QGIS I create a line that crosses a polygon twice. By using intersection, it will create a new shape file that gives me as a result two visible lines (the polygon cut the line). With geometry ...
1
vote
2answers
37 views

QGIS place labels next to the beggining or ending points of Linestrings but above the Linestring

I've got a Linestrings layer. Each Linestring has among other fields, these ones: id ENTRY EXIT 1 S1 E2 2 S1 E3 3 S1 E3 4 S1 E3 5 S1 E3 6 S1 E1 7 ...
1
vote
0answers
19 views

Per-pixel Descriptive Statistics through multiple Raster layers

I'm looking for computing different descriptive statistics through a set of raster layers. I need to make it with a python script capable of running into a standalone tool within the QGIS. To do so ...
2
votes
1answer
36 views

Why aren't my integer columns available for graduated styling?

I have a layer with graduated styling based on an integer column. When I duplicate the layer to make a similar styling based on another integer column, none of the columns are available for graduated ...
3
votes
2answers
106 views

Automatic numbering of points during digitization in QGIS?

Does somebody know how to automatically number the points during digitization in Qgis. To explain, when I create the new point there is the window where I must to type the point number. Is there any ...
1
vote
1answer
25 views

Why the street label is not showing in a feature in QGIS 2.14.2?

Why this street label is not visible even with zoom? It has 'name' in it... Here_qgis2.14.2_file
3
votes
1answer
83 views

QGIS Select overlapped feature

I have points that are not equal but the distance between them is so small that it can't be seen even at scale 200k:1. I calculated the distance between these points and add it as attribute. Now I ...
2
votes
0answers
24 views

Semi, third, quarter circle and other compound style symbols in QGIS?

I think I used quarter (and other) circles in QGIS in the past. But it might be as well that it was only in different software. Anyway now I am not able to find in symbols any option for compound ...
0
votes
0answers
26 views

Polylines and polygons - QGIS-2.14.3-1

After extracting contour lines from a DEM (obtaining polylines), and transforming them to polygons, I export the vector layer with polygons to a DXF. Then I import the DXF into Corel Draw to manage ...
0
votes
1answer
22 views

How to access the options of the Label Properties dialog in QGIS2.14.2?

The Change Label tool has a Label Properties dialog but the options are greyed out. How to access them?
1
vote
0answers
16 views

how to show all features visible on map?

i have restored on mssql a backup file and added it on qgis but it shows only some features NOT all features. i want all features to be shown on map.
2
votes
1answer
29 views

Why do labels in exports using HERE tiles appear tiny?

I am trying to export images from the QGIS print composer, the exported image has a basemap that is loaded from an XML file following this questions method. The export doesn't look at all like the ...
1
vote
0answers
14 views

Neighborhood analyses with GRASS/QGIS using ASTER GDEM

I have a problem related with this question (Old question without answer: R.Neighbors with large neighborhoods?). Basically, I want to estimate roughness of a given area, for which I was using QGIS, ...
2
votes
1answer
124 views

pyQGIS changing Paletted Raster Layers to Grayscale

I've written a plugin which imports a number of colour geoTifs (map tiles) and works correctly but it would be great to display these as Grayscale after loading in. The geoTifs load as paletted ...
1
vote
0answers
21 views

Joining polygons to points when the points fall in the intersection of polygons. QGIS

I am using QGIS. I am hoping to join a set of geocoded points to polygons in such a way that the new snapefile will be points that have a new field which lists the attributes of the polygon it lies in ...
1
vote
2answers
589 views

How to show a QGis map in Qt/C++ custom widget with QgsMapCanvas?

I'm trying to add a QGis map in Qt/C++ widget using QgsMapCanvas, but I have some problems... I'm working with the following environment: - Ubuntu 12.04 - QGis 2.8.1 - Qt Creator 2.4.1 (based on Qt ...
5
votes
3answers
148 views

Smoothing method for big polygons

I'm looking for an alternative to 'snakes method' for smoothing very big polygons, which I created from SRTM elevation datasets. The problem is that the smoothing is getting stuck after a while with ...
1
vote
1answer
14 views

How to “clean up” undesired values in a slope raster

I have a reclassified slope raster with 3 values in band 1. My problem is that I want to polygonize this layer, but the surface is so irregular with a lot of plots in terraces and because of this it ...
1
vote
0answers
11 views

How to avoid QGIS line width scaling when exporting geometry to KML?

I have shapefiles loaded as linear geometries in QGIS. I use the layer properties dialog to apply some styling to them (color + linewidth). The goal is to output each layer as KML file. My problem ...
1
vote
1answer
189 views

SAGA Cluster Analysis for grids projection issue

I am having an issue with the SAGA cluster analysis for grids tool within QGIS 2.4. I am actually taking this as an online class through Del Mar and we are going over supervised and unsupervised ...
2
votes
3answers
121 views

Sort a table by multiple columns in QGIS

In 2012 the answer was NO! How to sort by multiple fields at the same time? My data is in a SHP file, I want to sort by 3 fields. Has this changed in the last 4 years? == EDIT == A solution like ...
0
votes
1answer
26 views

How to edit a table in order to count the number of points in the same location?

Using QGIS, I have a point shapefile that has multiple points with same coordinates across different locations. I need a count of those points. For example there are 15 features that have the exact ...
1
vote
0answers
28 views

QGIS 2.14.3 can't attach oracle spatial table

when I try to attach spatial table in QGIS, the application close without errors. The tables which have problem have a UUID column: mslink NUMBER(10,0) NOT NULL, uuid RAW(16) ...
1
vote
2answers
484 views

PopUp with Images with QGIS2web

is it possible to create popups with images via QGIS2web? if yes, what would be the workflow? Couldn't it figure out yet. So any help is welcome! Thanks
0
votes
1answer
21 views

How to print maps portions one by one in QGIS 2.14.2?

I have a map divided into different regions. Each piece have a number assigned (eg. 27). I have a page configured for printing the region (territory) along with 4 pieces of attribute tables filtered ...
0
votes
2answers
25 views

QGIS error in merging large point shapefiles

While trying to merge 2 large point shapefiles using the merge shapefiles tool under the data management. These point files have over 20Gb and have the same coordinate system. Problem is, that the ...
0
votes
0answers
8 views

QGIS 2.14.3 export PostGIS layer to dxf issue

I am trying to export a PostGIS layer to dxf in QGIS (2.14.3) via Project>DXF-Export using the following settings (German GUI): When I open the resulting dxf in DWG TrueView 2016 I see nothing, but ...
1
vote
1answer
40 views

How to refresh MapCanvas while PyQGIS-script is running?

I try to write a PyQGIS script similar to this: Use of python console to prepare offline map from WMS (tile downloader). Basically there are two loops to pan the mapCanvas, refresh the mapCanvas and ...
2
votes
0answers
46 views

Selection by adjacent polygon features

I have a large polygon shapefile with lots of features from a model output, I need to remove anomalous features which are joined by a single vertex and part of a cluster of two. (example highlighted ...
0
votes
1answer
27 views

Creating grid layer of 2 km sq. and deciding X and Y parameters? [on hold]

How to create a Vector Gird polygon layer and what should put in the X and Y parameters when I would like to create a 2 km sq grid polygon
1
vote
1answer
57 views

QGIS show labels in beggining or ending points of Linestrings

I've got a Linestrings layer. Each Linestring has among other fields, these ones: id ENTRY EXIT 1 S1 E2 2 S1 E3 3 S1 E3 4 S1 E3 5 S1 E3 6 S1 E1 7 ...
3
votes
2answers
121 views

Fixed distance between two contours - Qgis 2.14.1

There is a possibility, when you select a contour line and give a fixed length of line, this line connects automatically to the next contour lines? I have two other questions on this subject but I do ...
3
votes
4answers
72 views

How to choose a fixed position to labels in QGIS 2.14.2? [duplicate]

How can I manually position these numbers for a better position in a polygon layer?
2
votes
1answer
212 views

gdal_calc works but I get a Python error at the end of each process

I have a problem while using gdal_calc by a .bat file. Here is the code : call "C:\OSGeo4w64\bin\o4w_env.bat" gdal_calc ...
2
votes
1answer
31 views

QGIS Python variable not updating after new features are inserted

I have the following script that sets the a feature id automatically after a new feature is digitized. I added the function inside the project's Macro section inside openProject() function: The ...
1
vote
0answers
53 views

Problem aligning historic map of Poland [on hold]

I have downloaded a historic map of Poland. I am having a problem aligning it to a modern map. I have tried various methods and coordinate system using over 50 points, but nothing works. It gets ...
4
votes
0answers
80 views

Import Vector data to QGIS from pdf and apply georeference

I am Using QGIS 2.14. I have a pdf created by Mapinfo, it contains multiple layers of vector data that I can open as separate vector layers in qgis. However no map projection data was saved to the ...
1
vote
1answer
34 views

QGIS automatic fill columns from referenced csv

I have what is probably quite an easy problem, however I'm not able to figure it out by myself. I work as a field researcher doing bird inventory. I collect the data via QGIS on an android-tablet, ...