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

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0
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1answer
10 views

How to snap polygons to lines?

How can I snap a polygon to a line? For example, I have a polygon which represents some meadows to snap over a line which represents a road. Thanks! Dani
2
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1answer
73 views

How to snap lines to nearest point?

Is there an easy way to snap lines to nearest point of either a line or a polygon? I don't see any snapping options for line layers as suggested on How to merge lines with slightly different endpoints ...
1
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2answers
107 views

Project house on WGS84

I have imported a DXF file of my house in QGIS. I also included an openstreetmap layer in WGS84 which also displays my house as a square. Naturally, my house from the DXF file is placed in the ocean ...
1
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0answers
13 views

Merge based on joined attribute in QGIS [duplicate]

I have a single layer of polygons (drawn around every zip code). I have a CSV file with territory numbers and the zip codes in each territory. I joined these and was able to color each territory ...
1
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0answers
22 views

Export from QGIS to Google Maps maintaining formatting

I'm totally new to QGIS so I'm not even sure this is possible. I've created a bunch of polygons within QGIS and they look just like I want them (color, transparency, etc.). What I'd like to do now ...
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0answers
11 views

Is there a QGIS equivalent to ArcGIS's Make OD Cost Matrix Layer (Network Analyst)? [duplicate]

I'm looking to create a OD cost distance matrix for a network data set I have created. Is there a way of doing this in QGIS which is akin to Make OD Cost Matrix Layer within ArcGIS's Network Analyst. ...
1
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1answer
11 views

QGIS Semi-automatic classification plugin install error on OS X 10.10: matplotlib.backends.backend_qt4agg

I have tried repeatedly to install the QGIS Semi-automatic classification plugin via both (1) Plugins > Install & Manage Plugins and (2) manually based on other comments I found here, but I ...
1
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1answer
37 views

QGIS Google Maps Coordinate System

I have some Points in Shapefile with BC Albers Coordinate Syetem and I need to Project them to Google Maps Lat and Long. I tried to do this by using WGS 84 / Pseudo Mercator EPSG: 3857 and ...
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0answers
9 views

Coloring multilinestringzm M values in QGIS

I have output from a geophysical technique that produces X,Y,Z and scalar value for millions of points, which have been stitched together appropriately (by networkx if it matters) into ...
2
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0answers
31 views

QGIS on UHD screen

I've got a new laptop that came with a 4k UHD screen. The GUI on QGIS doesn't scale well making most of the menu elements too small to easily see. Is there a way to change the scale of the gui?
1
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0answers
23 views

Convert mapinfo styles toward qgis styles

Up to now, I has worked with mapinfo. I have a big vector layer (points) with a complex symbology. For several days, I gave up mainfo for qgis. Is there a way to converting my mapinfo files (.tab) ...
1
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0answers
34 views

Add field and number fields of different shape files

In my project I have 3 different shape files (shape1, shape2, shape3). All of them should get a new field (add field to attribute table). In this field I need to have a number (for shape1=1, shape2=2, ...
2
votes
3answers
139 views

Why script works on my computer but not on another?

The script below works perfectly fine in my computer. But when running the script on another computer, I receive an error: Error: Algorithm not found The computer has similar specifications to ...
2
votes
1answer
43 views

Construction of a square grid from a given centre (lat,lon) and direction of the sides

Let us consider a point (longitude, latitude) on Earth (location). How to construct a square grid around this point (taking this point as the centre of the square or intercept of the two diagonals) ...
2
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0answers
10 views

Importing ArcGIS and/or CAD template into QGIS print composer…Can it be done?

ArcGIS is used very widely in Environmental consultancy and the print/map templates used for reports are usually passed around in an MXD or CAD file format. Unfortunately we cannot afford ArcGIS and ...
3
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1answer
22 views

Copying features to new location

I want to copy some features from one layer and paste them onto another layer with all their attributes, but in a different geographic location. Is this possible? These are very small features a very ...
2
votes
1answer
11 views

CRS dialog no longer opening

I'm new to QGIS, so supect this is trivial, but it has frustrated me for the last hour or more... Last week whenever I added a csv as a layer once I'd filled in the first dialog it automatically ...
1
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0answers
16 views

How to make both the mouse button click event to do the different function

I am using the canvas event with mouse button click events. def canvasReleaseEvent(self, event): if event.button() == QtCore.Qt.LeftButton: print 'The left button event is',event ...
1
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0answers
12 views

Selecting elements from network with shortes path in QGIS?

I have a network of vector elements (let´s say 70 elements) that are connected in each node. Actually, it is a pipe network built with the help of GHydraulics ...
2
votes
1answer
26 views

How to get the attribute list of a point that is clicked on the map

I would like to double click a point on map and directly getting to its attributes. I'm too lazy to go through the list auf 400 items, just to find it. Is there any way to do this?
2
votes
1answer
37 views

Specific renaming of elements in Attribute table failing until closing and reopen attribute table

Well the title tells it already. I have a column name and 100 objects. I have given them all a name. Now I mentioned that I have written some wrong of them. So I tried to correct them by double click ...
2
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0answers
31 views

Computing Shannon-Weiner biodiversity index using QGis

I wonder if anybody has some experience in calculating biodiversity index (such as Shannon-Weiner) using QGis. I am also interested for similar experiences using R scripts within QGis. The analysis ...
1
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2answers
45 views

Is there a way of auto_increment for the ID column

I'm creating a fictive map and so I need to create polygon after polygon. Later on I export my data as geojson. But before that I aways have to go and give every polygon a unique ID. I don't need a ...
0
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0answers
18 views

QGIS Convert SHP to KML keep all attributes [duplicate]

I am trying to convert a SHP to KML in QGIS and want to keep all the attribute fields. As far as I can tell when you do this operation, you can only choose 2 fields (DescriptionField and NameField). ...
2
votes
1answer
33 views

Joining lines by X,Y AND Z coordinates

My task is to generate 3D polygons from line data, which will then be imported into TerraExplorer 3D presentation software. Problems arise when there are overlapping lines in 2D space, but which have ...
0
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1answer
31 views

How can I merge two lines in 2.6.1-Brighton?

When I try to merge two lines selecting them and using the Merge Tool in the Advanced Editing Menu I get an error which says that merging these lines would result in an incompatible geometry for this ...
3
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0answers
13 views

QGIS 2.6.1 Complex polygon not displayed properly

I append two images of the same shape file which contains a single polygon with several "lakes". In SAGA it displays correctly with all the lakes as transparent but in QGIS the larger lakes contain ...
1
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0answers
25 views

Using processing using other output (result from another algorithm) as input

I have a problem. I am developing a standalone app in python and I need to use processing algorithms. I was able to use one algorithm without erros but I need to run other processing algorithm which ...
2
votes
2answers
32 views

How to move features from one layer to another?

I have a polygon which belongs to a layer and I need to move it to another one. Is there a way to do it without drawing it again? Thanks! Dani
1
vote
1answer
20 views

QGIS Custom Symbols Group File Location

I am curious as to the location of the symbols group files. I have created numerous custom symbols, as well as symbol groups. I would like to share these with the people I work with. Thank you!
2
votes
1answer
20 views

QGIS print composer export excludes one layer

I am trying to export a map from QGIS print composer but the resulting files (I've tried all image, .svg, and .pdf formats) do not appear as the map did in the composer. It is as if one of the raster ...
2
votes
1answer
30 views

QGIS toolbars source code

I can see the source code of the core QGIS plugins from the repository in github. But is there any repository of source codes for QGIS toolbars also?
1
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2answers
19 views

Imported TIF has dark gray background instead of white

using QGIS 2.6 I import a TIF file, and expect the import to show an image that has black lines on a white background (with some other colors here and there), as the native windows viewer will see a ...
1
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0answers
16 views

QGIS procedure for Multidirectional, oblique-weighted, shaded-relief?

Is QGIS capable of the multidirectional, oblique-weighted,shaded-relief method described at http://pubs.usgs.gov/of/1992/of92-422/of92-422.pdf ? If so, what are the steps necessary in QGIS to ...
0
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1answer
43 views

Fill polygons via data-defined pie charts

I am trying to summarize my polygons by each's distribution of some variable. To couch the discussion, let's say we wanted to summarize the demographics of each county (of a small state) by it's ...
1
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0answers
25 views

Custom QGIS 2.6 map tool - mouse click and release issue

I have create a custom map tool for QGIS 2.6, implementing a canvasReleaseEvent and canvasPressEvent. I can't though get the signals to work on one single mouseclick (I have to click twice). My map ...
2
votes
1answer
25 views

How to display QGIS plugin panel “OSM place search”?

It is possible to hide the panel for the experimental QGIS plug-in 'OSM place search' - but the panel is not listed (to re-display) under the menu item View | Panels. How can it be re-displayed?
0
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0answers
27 views

How to deal with contour error “Exception encountered: invalid index”

I have include vector layer using postgis database with filter(data between two dates) it work fine but after adding when I trying to make a contour from it I get error Exception encountered: ...
3
votes
0answers
25 views

How to display features only if labels are displayed?

In my maps there are several point layers, and each layer has a different labelling rule and priority. Sometime the point density is too high and the labelling engine is not displaying some labels, ...
1
vote
1answer
24 views

Change detection between two classifications in QGIS?

I have two raster classifications. They have the same number of classes which use the same ID (each class has a unique ID). I would like to get information on the changes between classes i.e., class 2 ...
1
vote
1answer
21 views

How to convert total station data (coordinates) to 3D model? [on hold]

i have my coordinates in .csv format and i want to convert it to a usable 3D model. How do i go about this or what software can i use to achieve this?
1
vote
2answers
17 views

QGIS upper round in field calculator

I need to to in the field calculator the following calc: toint(Field1 / 25.0) but i need to round the result to no decimal places but upwards. Exmaples: If 17/25 result should 1. If 25/25 result ...
0
votes
0answers
12 views

How to equally space points in a line using QGIS? [duplicate]

How do you place points in a straight line the same distance from each other in QGIS? Thanks
2
votes
3answers
32 views

QGIS: Get data in raster DTM from vectorpoints

I have a vector layer of points. Can I get an output from a rasterlayer which contains DTM-values (height) determined by my points placement?
3
votes
2answers
35 views

Send signal when attributes modified - QGIS 2.6

For a QGIS 2.6 python plugin, I am trying to send a signal when an attribute value is changed (values for an existing feature are updated or added and the attribute form dialog is accepted). This ...
1
vote
2answers
36 views

How to create an image of mean values from multiple NDVI images?

I have downloaded MODIS NDVI images of 12 months. I would like to create just 1 image with the mean values. I tried using IDRISI's 'NDVI compositing utility', but I get an error. Is there a way to do ...
4
votes
1answer
38 views

Shapefile layers in QGIS don't display unless I zoom out

I have two shapefile layers in a Qgis project that have problems with zooming. One is a line I copied/pasted in a new layer from a set of height contours and the other one is a polygon layer I created ...
1
vote
1answer
23 views

Why use QgsFeatureRequest() when iterating?

I am unclear on why one should use QgsFeatureRequest() when iterating over a file’s features. Let’s say I would like to print out all IDs in my currently active dataset. Now, most examples will ...
4
votes
2answers
29 views

Qgis - Projection Problem with EPSG:2272

I work in both Qgis and ArcGIS. Most of my data has been created using ArcGIS and all of my data should be in the EPSG:2272. When I add my data to Qgis, it does not recognize my projection and gives ...
3
votes
1answer
55 views

How to always disable the “add saved file to map” checkbox in Save as …?

I often use the "Save as.." dialog and just want the exported geojson file there. But he always enables the checkbox "add saved file to map". I really dislike it that way and it does not make any ...