All Questions
113 questions
2
votes
1
answer
174
views
Reflectance values from WorldView-1 images?
Most of the informations on WorldView images are related to the second and third version of the satellite. I own a WorldView-1 image (the black and white one) and I really need to find the reflectance ...
user68650
2
votes
1
answer
339
views
Joining data from two shapefiles in QGIS
I think there must be a straight forward answer to this but I haven't managed yet:
I have two shapefiles for the same watershed they are both divided into different areas with different erosion ...
- 143
3
votes
2
answers
1k
views
How to download Open Street Map data in QGIS? [closed]
I'm trying download data from OSM in QGIS via Openlayers plugin. Downloading is successfull, but when I add layer to project, many of the features are missing.
Is there any limitation, or does ...
- 39
2
votes
1
answer
457
views
Strange names of swedish cities [duplicate]
I got a GIS Data-set for swedish cities. The problem is that they have strange names such as:
Trädet
Jäla
Mjönäs
Älmhult
Did someone have the samoe problems? I think "ö" for instance mean ...
- 121
1
vote
1
answer
187
views
Can I consider QGIS OpenLayers basemaps as WMSs?
I am writing a manuscript about QGIS, and I categorized the data types into 3 classes according to popularity (raster, vector, web-data). Then I separated web-data to WMS and WFS. Under the heading ...
- 1,585
1
vote
1
answer
1k
views
Basic instructions for loading OS Terrain 50 data
Are there any basic instructions for using the OS Terrain data available online?
I do not have an issue extracting - it is all sat in a folder ready to go.
What I cannot work out how to do is to ...
- 211
4
votes
1
answer
6k
views
Change NODATA values to 0 in Qgis
I know this question has been asked already in this forum, but I couldn't find an easy (for me, a rookie) solution for my problem.
I have an RGB 3 band file which, in some pixels, has i.e.
R no data
...
3
votes
1
answer
247
views
Flow Mapping Data?
I have recently started experimenting with QGIS's flow mapping functionality. I am having trouble finding any origin/destination data online and I'm hoping someone can help?
It can be for anything. ...
- 693
0
votes
0
answers
148
views
Up-to date agricultural land use
I'm looking for data on commodities (corn and potato). Tools such as USDA's cropscape (http://nassgeodata.gmu.edu/CropScape/) are great but lack global cover.
I found this dataset http://www....
- 3,355
1
vote
3
answers
910
views
Free printable background map: land use, rivers, etc
I am looking for a free printable background map of europe which should look more or less like the OCM landscape:
land use, major rivers, coast lines
Is there any WMS or raster set whiche enables me ...
- 931
1
vote
0
answers
100
views
Repeated GPS coordinates in data are creating stacked points on map in QGIS
I have 30+ events of data collection for each GPS location (previous person on project has simply added new rows for each data collection period). When I import the excel file (via CSV format), each ...
- 11
3
votes
1
answer
788
views
Speed of people measured by gps
I was tracking tourist's movement patterns in a city with GPS and I would like to know the speed of all participants (60). The data were recorded and saved in gpx files, so in order to open it and ...
- 59
2
votes
2
answers
1k
views
Can't import certain tables from SQL Server to QGIS
This is a list of 193 zip codes and their geometries that do not import in QGIS.
This is a list of 999 Census Block Groups and their geometries that do import in QGIS.
This is the Add MSSQL Layer ...
- 21
2
votes
2
answers
4k
views
How to change the data type of columns of a vector layer in QGIS?
Is it possible to change the data type and attributions of data in QGIS?
Almost all of the variables which contains numbers should be changed in all of my vectors.
In ArcGIS the data type is ...
- 135
2
votes
1
answer
2k
views
Downloading data sets during installation
I can successfully install QGIS 2.8.1 on a Windows 7 machine but I get an error when downloading the Carlina, South Dakota and Alska data sets. The error message is http/1.0 504 Gateway Timeout. Looks ...
- 21
3
votes
1
answer
737
views
QGIS Categorized Symbology based on joined table
I am trying to create categorized symbology for a data layer. The column that I would like to base the categories on is a result of a table join. For some reason it isn't working. All of my polygons ...
- 161
3
votes
1
answer
206
views
non alignment of base layer and other vector layers
i'm sure you've encountered this problem repeatedly. i've tried all different methods.
Enable on the fly crs transformation.
go to settings and options to use crs data.
go to properties and change ...
- 41
1
vote
1
answer
229
views
Error in executing commands in GRASS GIS
I'm using Grass 6.4.3RC2. I have a problem because when I execute the command:
r.radcov csv_file=cell_list_hataDEM_umts_amc_testTEST.csv dem_map-AlbSRTMdem@PERMANENT clutter_map=AlbClut@PERMANENT ...
- 11
2
votes
1
answer
137
views
Oracle VectorLayer without geometry - How to get attributes?
I have a problem to iterating over a oracle VectorLayer without geometry in QGIS 2.6.
self.uri = QgsDataSourceURI()
self.uri.setConnection("localhost", "port", "xe", "name", "password")
self.uri....
- 21
2
votes
2
answers
12k
views
shapefile for mumbai area or section wise
I am working on a project in which i need to plot data on Mumbai city map section wise or area wise but i am not able to get Shapefile for the same.
Can anyone please provide me the link where i can ...
- 333
0
votes
2
answers
733
views
How to obtain data to create average precipitation in 2012?
I am currently doing a final project, which I have to create a map of 2012 average precipitation of lower 48 states by using natural neighbour interpolation. The problem is that how can I get the data?...
- 1
1
vote
2
answers
210
views
Where/how to find ortophotos
I am very new to Geographic Information Systems. I have a very basic inquery; How do I get hold of the newest ortophoto of South Africa to use as a background map for my GPS data? I'm using QGIS but I ...
- 25
3
votes
3
answers
220
views
Is there a way to shift data in an attribute table so that all attributes are moved to a different coordinate?
I have several shapefiles where the attribute table is composed of timestamped data that is appended to the coordinates. Because of the nature of my data, I need to apply a time lag so that the data ...
- 33
1
vote
0
answers
104
views
Is there a way to automate POI collection from websites?
I am searching for an easy method to get lots of points geotagged/georeferenzed into several shape files.
I am working at a project where I need to collect all parcel shops in germany (but I will try ...
- 242
5
votes
1
answer
2k
views
Sourcing GIS data from First World War (WW1)?
Simple question, but does anyone know where I can get some detailed (eg 1:10m scale) vector data from the First World War?
I've been through the archives here, but it seems the best sites for it ...
- 103
2
votes
2
answers
1k
views
QGIS - exercise data
I´m working currently through the QGIS training manual. However, the data for the spatial analysis exercise in chapter 9.4 (http://docs.qgis.org/2.2/en/docs/training_manual/complete_analysis/...
- 644
2
votes
0
answers
834
views
How do I automatically generate a spatial data catalogue from shape files and .gdbs?
I've recently inherited a whole bunch of spatial data (mostly shapefiles but some .gdbs) which relate to a bunch of different cities. I'm looking for a way to take an inventory of what data I've got ...
- 559
2
votes
1
answer
6k
views
How to automatically fill a lat/long in attribute table
I need to plot the distribution of a plant species on a map. I have created a shapefile for the species plots (name of file is PLANT). The coordinate system of this file is WGS84. On the attribute ...
- 21
0
votes
2
answers
1k
views
Seeking Metropolitan Statistical Area (MSA) KML data? [duplicate]
GIS is not my field. I need this data for an odd job at work.
I have been unsuccessful in finding the data from Google FusionTables but found (what I believe to be) the shapefile for MSA's from the US ...
- 1
4
votes
2
answers
540
views
Alternative to Spatial Query on large data
I have around 110000 points data spread around the world. the shapefile size is 116 Mb. I want to select points which are inside asia.
I have been using qgis but this time qgis is not being able to ...
- 8,390
-1
votes
1
answer
2k
views
Seeking GIS data about NYC's combined sewers (CSO) that's free to use? [closed]
I've located two sites that display the data that I'm looking for, but both lack exporting functions.
OASIS NYC
and
maps.nyc/gov
Otherwise I can't locate this data anywhere in a format I can use in ...
5
votes
1
answer
945
views
Why am I losing part of my raster when I reproject?
QGIS 2.0
Working with tiff raster file.
Reprojections are in WGS84 Mercator.
Here is my problem: I am trying to use buffers or urban areas to analyze light intensity on a raster layer. I want 30 ...
- 145
1
vote
1
answer
48
views
Plugins to guide inexperienced users: updating shapefiles and managing data
I am attempting to find a way to block adding features while certain attributes are not yet added. This would be useful in order to guide inexperienced clients and employees with the process of adding ...
- 2,125
2
votes
1
answer
117
views
Installing Demo Datasets for QGIS
I installed QGIS without selecting the demo datasets. Now I realise that was a mistake.
Is there a way to install these after QGIS installation or do I have to uninstall completely and re-install?
- 191
3
votes
2
answers
342
views
Why can't I open a .xls with QGIS in OSX?
I'm trying to open an .xlswith QGIS 1.8 in a Mac, I'm loading the vector layer from Add new vector layeretc. etc. the procedure works in Windows but not in Mac where I have an error Invalid source ...
- 2,078
1
vote
2
answers
963
views
County-Level Ethnic Shapefile: United States
My professor usually provides the shapefiles that we deal with in our analyses of the United States--population, votes, etc., but I'd like to know how I can get these myself. I'd like, in particular, ...
- 141
2
votes
2
answers
3k
views
Adding MS Access Table as X,Y Points using QGIS? [duplicate]
Can you add an MS Access table as X,Y points in the same way you can Add X,Y data in ArcMap using:
File --> Add Data --> Add X,Y Data
- 2,291
-1
votes
1
answer
2k
views
How to open .bds file in QGIS?
I have a Land Registry boundary file which is in .bds (Base Dataset) format, a native file format in Cadcorp SIS. I want to open this file in QGIS. Is it possible, or do I have to do any conversions?
- 1,462
2
votes
0
answers
2k
views
How to get National Geographic basemap in QGIS?
I'm proficient in ESRI's products and recently started using QGIS.
I've used the national geographic world map (NatGeo_World_Map) in ArcMap, but am struggling to replicate this in QGIS. The map is ...
- 21
1
vote
2
answers
456
views
Is it possible to change CRS without the .prj file?
I'm working with QGIS and trying to change the CRS of some maps. Is is possible to do it without the .prj file?
- 915
2
votes
1
answer
284
views
Conversion of coordinates of "Bochum coordinate system"
I need to convert historic coordinate data into more recent Gauß-Krueger data. Specifically, I need to convert "Bochum coordinates" used till 1960 in the local coal mines into DHDN/Gauß-Krüger zone 2 (...
1
vote
1
answer
539
views
How to sum the values for bins with the same location?
I have two maps in CSV form, each has a latitude, longitude, and value column. Since not all the positions in one map are in another map, is there any way in QGIS to display a new map which only shows ...
- 11
0
votes
1
answer
171
views
Draw lines for existing list of data
I have a csv file containing information for loads of lines (dates, road names, condition information, etc etc) but which have no geographical information (other than the association of road name)
Is ...
- 25
5
votes
1
answer
2k
views
How to convert a column of numeric IDs to letters?
I'm working with qgis 1.8.0. I divided a map into 500 features (small rectangles), and now I have the doubt if there is any way to change the ID of the attributes from numbers to letters? When I did ...
- 915
5
votes
1
answer
444
views
Determining size of grid cells created by vector grid tool of QGIS?
I am 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?
- 915
0
votes
1
answer
103
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 ...
- 915
3
votes
1
answer
813
views
Divide shapefile
I'm new working with QGIS 1.8.0 and wanted to know if its possible to subdivide a map (shapefile, which is round-like) into small squares but following the outer round contour of the map? I tried with ...
- 915
0
votes
1
answer
313
views
Why is the CSVT file changing my real values to null?
I made a CSVT file to change desired real data to string data. After importing the original CSV file, that was linked by file name to the CSVT file, the string data appears as normal however all the ...
0
votes
2
answers
510
views
Is there a way to convert multiple columns at once from string to text, or to other data formats?
I have multiple data fields that need to be converted from string to text files. When I save them as "text" in excel or open office, they still load up as string files in QGIS. How can I convert more ...
- 303
2
votes
2
answers
3k
views
Why is QGIS reading in my CSV numeric data as string data, and how do I change it? [duplicate]
QGIS keeps reading in my numeric data from .csv files as string data. This means I have to figure out how to read it in with the proper data type, or convert it back to numeric inside of QGIS, ...
- 21