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

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1answer
36 views

How to access the different panels in QGIS Composer? [duplicate]

I accidentally closed the tabs in composer: Composition and Properties, I think it is called. The question: How can I open them again?
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0answers
83 views

Can I speed up very long connection times to a PostGIS DB caused by complex views?

When connecting to a PostGIS database to add a postgis layer, all table and views are scanned by Qgis in order to define the geometry type (if I understand well the query performed). My problem is ...
3
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2answers
144 views

GRASS v.rast.stats missing in sextante toolbox

I am new in the QGIS world and also with GRASS. I am really interested in using v.rast.stats as is doing exactly what I need. My problem is that I am not able to find it inside sextante in QGIS and I ...
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1answer
140 views

How to create a polygon feature using Python?

I'm making a plugin for Quantum GIS in python. I have a polygon layer and want to create a new feature. So far, I have this because I need a polygon geometry to add the feature: surface = ...
3
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1answer
75 views

Why can't I clip vectors with 2 different projections?

I am using QGIS. I am trying to clip parcel data with a stream buffer. The two have different projections. Parcels are NAD83 State plane feet and streams are NAD83 State plane meters. I keep ...
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0answers
22 views

Trouble making heat map - red square [duplicate]

I'm a beginner to QGIS and I'm having trouble making my heat map. I'm using QGIS 1.8 and Win7. I imported a CSV file with around a 1000 points (X Y coords - WGS84). When I try to make a heat map ...
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1answer
89 views

How do I add a lot of data to a shape file in QGis?

I have some nice shapefiles from Agesic in Uruguay, I need to add to them some information (not as shapefile) that I got from Dinamige to the attribute table. These institution are not the point, the ...
3
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2answers
306 views

How to extract all Way elements tagged as highways from OSM data using QGIS?

I want to extract/filter in all Way elements within a specific region tagged as 'highway' from an OSM file. I am currently thinking of using a Python library called osmread (by A Dezhin) that I ...
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0answers
103 views

Why am I unable to save shapefiles layers? (other layers work fine)

I'm a very new user on QGIS. I've managed to find mostly all I needed to use the software, however today I came across some problems similar to those encounted by [someone else][1]. However, when I ...
7
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2answers
909 views

Version editing for Postgresql 9.2.4 / postGIS 2

Background: I am "building" a GIS with PostgreSQL 9.2.4 / PostGIS 2 as the database and QGIS 1.8.0 as the geographic application. There will be multiple users accessing, editing and viewing the data ...
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1answer
41 views

How to handle a UnicodeEncodeError with sampling tool?

I'm using qgis and I keep getting an error when using the point sampling tool, its keeping me from getting the sampling done. Does anyone has an idea what is it about? Thanks!
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0answers
401 views

PyQGIS CRS on the fly reprojetion

As a first step of a pyqgis plugin I'm trying to import several shape files at once. To get them aligned, using the GUI, I'd enable on the fly reprojections and set the project crs to WGS84. I'd then ...
5
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2answers
468 views

Clip polygons with other polygons based on matching attributes

I have two shapefiles, one which contains event locations and the the other of which represents regions where events take place. Events polygons with year and region_name attributes Regions ...
1
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1answer
53 views

How to match a shapefile with seconds as units with other layers

I have some shapefile in coordinate seconds (longitude&latitude multiply 3600). I have open google street layer by openlayers plugin in qgis. how to match my shapefile with google street layer ...
3
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1answer
99 views

How to tell the size of grid cells created by the vector grid tool?

Im working with qgis 1.8.0 and Im making a vector grid on a map. Does someone know how big are the squares if the grid settings look like in the picture? Thanks for your time!
3
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1answer
207 views

How to match google openlayer and shapefile data?

i've installed openlayers plugin and opened google satellite layer in qgis. for a point in beijing china. it's show 12961957,4852605 coordinate in blew status bar. and it should be ...
0
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1answer
187 views

How to create one print layout with 3 different maps of the same area?

I have a problem with the Qgis print composer: I want to create a print layout with 3 different statuses of the same geographical area, stylizing with 3 different fields. So far everything works but ...
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1answer
651 views

QGIS 1.8 in Linuxmint 14 (Ubuntu 12.10)

I have Linux Mint 14 KDE which is based on Ubuntu 12.10 Quantal. In the QGIS download page, there's no "Quantal" repositiries. I'm trying to use the "Precise" repositories, but I'm not allowed to ...
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1answer
322 views

QGIS - adding timestamps to spatialite data during data collection

I am trying to do field data collection using QGIS. One of the features that I regard as necessary for data management is timestamps. For example, a timestamp can indicate that an inspection record ...
6
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1answer
784 views

Is SpatiaLite or SQLite Spatial an Accepted Standard?

The reason why I ask this is because I have been undertaking some testing and have found that there seems to be many implementation and not all of them are interchangeable. For example: FME can read ...
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1answer
4k views

How can I convert/transform coordinates from ETRS89 to WGS84 Utm 36N in QGis

I am a student and just getting to know qgis. At the momment I have to combine data which had been measured in ETRS89 with data in WGS84 UTM 36N. I created several vektorlayers for the data in ETRS89. ...
2
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2answers
120 views

How to adjust raster size for usage in raster calculator?

I want to make a visibility analysis of planned wind turbines in my region. I have a DEM raster and a polygon describing the possible area where the wind turbines might be set up. People are ...
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0answers
63 views

detect signal where delete polygon in qgis?

I am working with QGIS and i want when i delete a polygon and then i commit this action I detect the signal of this operation and use it in python script, I tryed this but dont work: def delete(): ...
3
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2answers
1k views

How to set proportional value in legend?

I have a GIS table with traffic flows.The thickness is proportional to the traffic value and I'd like to have a little legend with 3 links proportional to setted value (eg: link1 proportional to 100 ...
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1answer
251 views

PostgreSQL/GIS table relations in QGIS 1.8.0

I am building a database in PostgreSQL 9.2 with the PostGIS 2.0 extension. The database consists of a schema called Water which contains water related geographic features (as example, boreholes and ...
0
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1answer
168 views

How to make a Marker moving along the line in QGIS?

I have some questions about simulator moving on the QGIS map. On a vector layer, selected some points to make a polyline, and, let a Vertex Marker moving along the polyline. Now, I want to moving the ...
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1answer
142 views

connect signal to function with arguments

Hello I have this function on python that take 2 arguments: def niveau(controName,idNiveau): ........ I want to connect it to this signal: ...
2
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1answer
222 views

How many active QGIS users are there in total?

I'm the CEO of MangoMap which is a online GIS data management and web map publication platform, we're big QGIS fans and make extensive use of it. We would really love to integrate MangoMap more ...
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1answer
201 views

What is the correct coordinate system for google geocoded text file layers?

When importing a text file containing lat/longs geocoded from something like GPSVisualizer.com into QGIS, what is the correct coordinate system to select? Most web services (GpsVisualizer included) ...
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0answers
149 views

Can QGIS Measure Line tool compute correct geodetic distance?

As I understood, this tool normally shows distance in the project CRS units, not the geodetic meters (despite it actually says the distance is in meters). However, now I read (Section III, 4 - ...
3
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0answers
116 views

Can extracting raster values work in polygons' CRS without raster resampling?

I am trying to extract raster values using polygon layer with different CRS. Raster is in WGS84 (EPSG:4326) and the polygons in UTM (EPSG:23031). 1. If I want to work in the projection of the ...
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1answer
191 views

Sum of values within a buffer polygon

I need to do the following in QGIS and hope so much anyone could help. I have a vector layer with points. Each point represents a firm with the number of employees in the attribute table. I want to ...
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1answer
245 views

Define transparent color in singleband pseudocolor raster layer style

Can I somehow define "transparent" color for values higher than 32000 in raster layer? See the style dialog:
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0answers
164 views

How do I edit a shapefile DBF to repair an extra row?

Something got screwed up and now the rows of my DBF beyond #1210 are offset by one, meaning that each shape has the attributes that should be assigned to the next shape. If I were in a spreadsheet ...
4
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1answer
2k views

How do you import a .SHP into Sketch-Up?

Does anyone know how to use a .SHP in Trimble Sketch-Up? I have tried exporting to KML and CAD from QGIS, but the KML file doesn't read in Sketch-Up. Thanks! -m
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0answers
44 views

How can I import layers into a database?

According to the QGIS User Guide (release 1.8.0, page 203/204) I only have to drag a layer from the QGIS Browser to the DB Manager. But for me this does not work.
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4answers
235 views

Buffer in QGIS/R is 650-670 m wide instead of 500 m

I am trying to make a 500 m buffer for my polyline layer. Unexpectedly, I receive buffer varying from 650 to 670 m, depending on location. As many resources recommend to use UTM before making a ...
4
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1answer
361 views

QGis Zonal Statistics Plugin NoData included in Calculations

I have been trying to use the QGIS zonal statistics plugin. My raster has a nodata value of -99999 and all other values are positive. After computing the mean zonal statistics there are a number of ...
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1answer
301 views

QSpatialite : import multiple TXT/CSV

I'm using QSpatialite only. I don't have spatialite-gui neither the shell. I want to import multiple TXT/CSV at one time. How is it possible to do that ? I found nothing on the internet. Thanks
2
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1answer
461 views

How to align (georeference) images using QGIS?

I'm completely new to all this. I'm trying to make a map of Han dynasty-era China for a mod for a game called Crusader Kings 2. I've downloaded QGIS and Natural Earth 2, but I need this image to ...
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2answers
162 views

Exporting raster data from QGIS in chosen projection

EDIT: it is seeming like some of the time my last method will lead to a correct projection, some of the time it will not. Unsure what's happening there but at least trial and error will get me ...
0
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0answers
52 views

Vector grid out of range

I'm working with QGIS 1.8.0 trying to do some vector grid to a map. This shapefile (the original is a zip and has the following files .dbf, .prj, .sbn, .sbx, .shp, .shx) has some strange CRS and I ...
3
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1answer
299 views

What's the unit of measurements produced by “sum line lengths”?

My goal is to find the total length of roads per county for a particular state. You would think there would be a simple government spreadsheet with this information in it.... I cannot figure out how ...
2
votes
1answer
169 views

Looking for a tool that will place the cursor to a specific x,y coordinate

I am a new user to Quantum GIS. I am looking for a tool/function that will allow a user to type in coordinates, and place the cursor on that exact position. This is for navigation in the field... ...
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0answers
25 views

Dwg to shp in Geoserver [duplicate]

I am trying to load dwg in geoserver and show it in openlayers, so I saved the dwg as dxf with autocad. Then I used qgis to save the dxf as shp. But when I am trying to load the shp with geoserver ...
3
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1answer
159 views

How to select all multipoint features from a point layer?

I'm connecting to WFS layer by qgis. On some layer I've got points features and few multi-point features. Whole layer contains about 1000 features, how can I do some query just to know which features ...
0
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1answer
48 views

Sampling from interpolated data layer

Im working with QGIS 1.8.0 and wanted to ask you how can I assign to each of the small squares of the map (I have the coordinates of the center each of them) values from an interpolated data layer as ...
1
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1answer
604 views

QGIS python - reference a layer in the table of contents

I'm trying to create a plugin for QGIS using python, But need some help. I want to 1.Zoom to a layer and 2. make the layer visible(switch off or on). But I have managed to zoom to an active layer by ...
2
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2answers
2k views

How to draw bar diagrams on the map?

I need to draw simple histograms in QGIS version 1.8 from an imported DB. I need a double bar diagrams (eg: male/female - in/out) but I only find the possibility to set pie charts. Is it possible to ...
0
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1answer
117 views

How can I mosaic raster data which have different number of bands ( 3 and 4)?

I would like to mosaic 100 raster data. several raster data's band are 3, though last data have 4 bands. How can I mosaic raster data which have different number of bands?? If somebody knows how to ...