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

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2
votes
1answer
31 views

How do I make this into a working CRS in ArcGIS?

+proj=tmerc +lat_0=0 +lon_0=-114 +k=0.9999 +x_0=0 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs I have this text string which I successfully used to project data in QGIS. How do I use ...
3
votes
2answers
34 views

Why do I get an empty shapefile when converting this KMZ in QGIS?

I have downloaded a KMZ file containing global elevation information. I have tried to convert the data to a shapefile using qgis (save as shape option) and using the zonum solutions website but both ...
1
vote
0answers
27 views

Converting QGIS Labels to a Polygon Shapefile

I am trying to create an annotation feature from labels and then export this out as a polygon shapefile (the resulting shapefile can then be loaded into ArcGIS online to basically have labels without ...
1
vote
2answers
52 views

Conversion of point grid to a raster with open source tools (Gdal, QGIS …)

I'm looking to do something which seem simple to me, but I haven't found a solution since 2 days I looked for. I've got a Postgis DB with lot of points (WGS84) spaced of 100 meters which cover a ...
0
votes
0answers
14 views

Multiparts and Multigeometries: checking for multigeometries with PyQGIS?

I have been working with PyQGIS and writing a small script to check whether the layers I have in the MapCanvas have geometries of type "MultiXX" because I want to run the "Multipart to Singleparts" ...
2
votes
1answer
31 views

How to fix “The selected file already seems to have a world file!” when image hasn't been georeferenced before?

I am georeferencing historical aerials from 1988 in QGIS 2.2.0. Sometimes it works perfectly and other times after I have places my points and start the georeferencer a window pops up saying: "The ...
0
votes
0answers
12 views

How to cut a polygon without snapping to a vertex?

I am familiar with editing polygon files in QGIS version 1.8. I have recently upgraded to version 2.0 but there seems to be a difference in the way it processes cuts. I used to be able to cut a ...
0
votes
0answers
14 views

How to rasterize a point layer? Cell value should be 1 if feature attribute is 1

I’m a fairly experienced GIS user, but I’m new to QGIS. I’m using version 2.2, and I’m trying to convert a point data layer into a raster data layer using the Rasterize tool. The point data layer has ...
0
votes
0answers
10 views

In QGIS Process Modeller, is it possible to automatically run a function on several layers without listing all combinations?

Trying to develop a Model which includes finding any intersections between layers and then merging them all into a single layer. I have 12 layers in total, it's not really efficient to list all the ...
0
votes
1answer
45 views

How to create input data for the LRS plugin from an excel table without coordinates?

I'm working with QGIS 2.2.0. I want to add a shapefile from an excel file that has informations I want to use in the LRS plugin. The excel file has no geographic information. Every time I try to save ...
0
votes
1answer
32 views

How to join information from an excel table to a road feature in QGIS?

I'm working with GQIS 2.2.0 Valmiera. I've made a shapefile of a road that consists in a single line. Now I want to add information that I have in an excel table about several point in the road. How ...
2
votes
1answer
47 views

Why does QGIS 2.2 Atlas not work?

I have problem with atlas generation in QGIS 2.2. I'd like to export pdf map with 2 maps window and use coverage layer function. Atlas doesn't iterate across the features in coverage layer. First ...
-1
votes
1answer
45 views

Can QGIS alone can be used without installing grass?

can QGIS alone can be used without installing grass? i want to use functions of grass and i am not interested to create mapset and all. just with raster and vector files, i want to study temporal ...
0
votes
0answers
22 views

How to calculate the area of an ellipse on the earth's surface using Python?

I have a dataset consisting of GPS coordinates. I use a clustering algorithm to generate a two dimensional Gaussian for me. The Gaussian takes the shape of an ellipse if visualized on the map. ...
0
votes
1answer
63 views
+100

QGis: scripting the map rendering (multiple similar maps from one shapefile)

I would like to ask for advice on creating a Python script that will provide the opportunity to render a plenty of similar maps (with the same extent, projection, layout, color scheme and composition, ...
0
votes
0answers
17 views

MSSQL Connection settings for QGIS

OK first lets get the blond elements out of the way- I'm not asking for how I connect to my actual database. What I'm asking for is an example or screen shot of the entries required when setting up a ...
0
votes
1answer
31 views

Producing gradients between shapefiles and using original boundarys as isoclines (lines)

to produce a bathmertical map of a river bed I draw shapefiles showing the different depths based on satellite images taken during different tidal levels (deepest, 2nd deepest, 3rd deepest, shore ...
2
votes
2answers
46 views

What's the use of the buffer function in field calculator?

I'm trying to find out how the buffer command in the filed calculator works. I tried to create a new field to my point shapefile (integer) with the following: buffer ($geometry, 100) but no ...
0
votes
0answers
13 views

QGIS map tip / label showing a table

I have a MSSQQL Spatiatal layer with Point data (borehole locations, pointID) and a joint table lithology (soil info per borehole, pointID, depth from, depth to, constituent) Is there a way to use ...
0
votes
1answer
17 views

QGIS 2.2 Atlas - Blank Export

I've got a map laid out how I want it in QGIS 2.2, using the "Atlas Generation" feature. When I preview the atlas, all 7 pages look proper and seem to work fine. However, I cannot export them to any ...
0
votes
0answers
11 views

Can a joined-layer have its attribute changed depending on what layers are selected/deselected?

Using QGIS, I have a polygon-grid layer which covers everything, Layer_All joined with 2 other grid layers: Layer_1 and Layer_2, both of which intersect at various points. I would like Layer_All to ...
2
votes
1answer
36 views

QGIS - move a point object to specific coordinate

Is there a way of select an object (point, polygon) and move it to a specific coordinate (manually inserted)? (with Numerical Digitize plugin can not make a move of the object but rather it creates ...
1
vote
0answers
40 views

Sorting points to flight path route

Original question: I would like to sort my points in QGIS. See image Restated question: The grid tool currently numbers by starting at R1C1 and going to R1Cx, then R2C1 to R2Cx. How do I number the ...
0
votes
1answer
22 views

Rasterization in different bands

I have a set of vector based shape files, representing different types of ground coverage in a city (for ex: roads, buildings, open field,...). For the algorithm that I want to run on it, I need just ...
1
vote
1answer
18 views

How to set the output extents of rasterization in QGIS

I am trying to rasterize a bunch of vector based shape files in QGIS. All these files are covering certain types of ground use in a city (houses, street, open field,...). I need these files to be ...
0
votes
1answer
43 views

How to remove black box around georeferenced grayscale image in QGIS?

i'am trying to georeference a grayscale image (*.tif) in QGIS 2.2.0 Valmeria. It is working but QGIS draws a black box around the georeferenced raster image. If i use the option set 0 transparent, not ...
0
votes
0answers
17 views

insertVertex giving false in pyQGIS

I have this code from my plugin which work in Qgis 1.8 and I am trying to make it work in 2.0. I want to insert a coordinate x and y into a polyline after the last entry. points = geom.asPolyline() ...
0
votes
0answers
7 views

Credential Dialog, disabling default Realm information messages disclosing password

I'm using the QgsCredentialDialog for determining user access to the database. When a user is failing to log in correctly the log in credentials are shown in the dialog (Fig. 1). Despite the ...
3
votes
1answer
38 views

Expand raster extent and set expanded values using nearest neighbor sampling

I have run a hydrodynamic model which has given me a grid of surface elevations throughout a bay. I am trying to process the results in ArcMap (or QGIS if needed). My goal is to take the current grid ...
0
votes
0answers
27 views

How to set raster values to NULL?

how can I define values to null? I tried it with the processing reclassify tool but I always get an error log (cannot open the result shape...or something like that).
0
votes
1answer
20 views

Clipping several raster layers to the same exact size QGIS

I'm new to QGIS, sorry if this is a newbie question... I need to clip about 40 different raster layers from one vector layer (that has the boundaries of 4 neighboring countries) but I need them all to ...
0
votes
1answer
49 views

How do i create a flow line map for my data?

I am trying to illustrate a passenger travel flow map from a road terminal to several destinations on a road layer. I have QGis and ArcGIS, but I don't know much on how to start the work. I already ...
1
vote
0answers
45 views

Automating the production of GPS-compatible map tiles from georeferenced raster maps

I have a set of TIFF maps that I want to load onto Garmin GPS 62s units. The maximum size for each tile on the GPS is 3Mb and less than 1 million pixels. I manually produced one tile, following this ...
0
votes
1answer
31 views

How to convert this geometry location format to a qgis usable format?

I am a beginner with regard to dealing with gis information, so please bear with me. I would be obliged if someone could help. I have data on asssembly constituencies of Delhi, with these ...
1
vote
2answers
66 views

How to increase label size of OpenLayers plugin basemap layers?

For QGIS 2.2.0-Valmiera, how does one increase the label size of OpenStreetMap layer or any other basemap layer? Presently the labels are way too small to read. For example, I find that for the same ...
1
vote
1answer
36 views

Intersection of polygons QGIS 2.2

I have a polygon layer with many circle polygons in it, which are overlapping each other. I now would like to cut of the overlapping areas at their cutting edge: I use QGIS 2.2 and couldn't ...
1
vote
0answers
12 views

Why is node tool deleting unselected points in lines?

I am freehand editing lines to a shapefile on Mac QGIS 2.2.0, and have my snap settings at vertex and segment @ 20 pixels. The lines are roadways and I have merged them all into one feature and merged ...
0
votes
3answers
72 views

From shapefiles to a printed map, what are the options? [closed]

I will soon start a new map project where the data is a set of shape-files and the outcome will be a printed (50x70 cm) large scale topographical map (1:50000). Earlier I've been using ArcGIS together ...
0
votes
0answers
33 views

Error openlayers plugin in qgis [duplicate]

I did the following steps: I put the projection in 3857 and I enabled the project on the fly Open a vector shape layer in the projection 4326 I enabled the openlayers plugin Clicked enabled ...
1
vote
1answer
42 views

Question about BNG coordinate systems

I'm historically a user of MapInfo Professional but have recently started using FME and have been talked into now testing out a copy of QGIS. The main problem I've come across is that the coordinate ...
0
votes
0answers
34 views

Problem reducing the width of the attributes fields of a shapefile using python

I have a shapefile with rather long attribute widths (which is resulting in a rather large file). I am trying to trim it in python, here is my code: layer = qgis.utils.iface.activeLayer() ...
0
votes
1answer
33 views

why can't i export geometry data from a shapefile?

I saved the layer using "vector save as" box but even when adding GEOMETRY=AS_XY in the layer box, the csv only showed the id and no gemetry data.
0
votes
1answer
51 views

Help in importing excel data

I have downloaded the hourly solar radiation data from NREL which is in CSV format but the problem is that the file does not have an exclusive column called latitude and longitude. There are 100s of ...
0
votes
0answers
15 views

What does this python error in terrain profile plugin mean?

I get this message when trying to create cross sections from a raster layer. It happens only when I try to plot from a selected polyline. When I choose temporary polyline, the plugin works fine.
0
votes
1answer
42 views

Replacement of QVariant and setAttributeMap in PyQGIS

I am updating a plugin for QGIS 1.8 to QGIS 2.x. I have the code below. The setAttributeMap does not exist anymore. I have replaced it with fet.setAttributes and it seems to work. When using ...
2
votes
1answer
40 views

Why do layers appear in the wrong order in QGIS 2.2?

I have a problem with in which order my vector and raster layers appear in QGIS. I have raster that I want to be the background of my other layers (vector). I place the vector layers on top in the ...
1
vote
2answers
66 views

Exporting PDF from QGIS with print composer without destroying fonts

So I'm making this nice map with a lot of labels which are going to end up in a book. Since the labels doesn't end up exactly where I want them I'd like to move them some in Illustrator after ...
0
votes
0answers
12 views

Link/unlink buttions in the Attribute Table's Form View

Toggling the edit button, in the Form View/Table View, buttons for adding/deleting a record is available. Two additional buttons are also available (Fig. 1). From the look of the icons they perform ...
0
votes
2answers
20 views

how to put a cropped selection of a map into the composer

I have a map canvas and I want to have a portion of that canvas printed. I adjust the canvas window in QGIS to show what I want to print and then add the map to the composer. The results are very ...
0
votes
1answer
26 views

How to work with Microstation DGN v8i files in QGIS?

I have a set of multiple files in DGN format (Microstation V8i). I would like to work with them in Qgis. Since QGIS only support pre-V8i dgn files, I cannot directly open the files. My first idea was ...