Raster is a data format consisting of regular grids of values, usually stored in an image-like format.

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Mapnik PGRaster Plugin creating 8x8 tiles with visible boundaries

I have used the latest addition to Mapnik PGRaster plugin (https://github.com/mapnik/mapnik/tree/2.3.x) by Strk(https://github.com/strk/mapnik/tree/2.3.x-pgraster) and merged recently. I am able to ...
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36 views

Multiply Rasters with Scalar Numbers as Input in QGIS Modeler

I built a little model in the QGIS modelbuilder which uses the raster calculator with the command gt(a,threshold) I need to run the model with varying thresholds from 2 to 30 so it would be ...
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41 views

Easy way to extract raster cells OUTSIDE a vector (Mask) layer in QGIS?

I have a raster file but am only interested in the cells outside a certain polygon. This polygon is very iregular and scattered across the raster. Is there any easy way to extract only the cells ...
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58 views

PostGIS Raster functions not working

Hopefully I have a simple question that I'm not phrasing correctly in google. I'm trying to learn about storing and producing rasters in PostGIS. There are tons of examples and documentation online ...
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96 views

Correlation between point feature (disease) and elevation

I have a problem! How can I calculate the correlation between point feature and Dem raster? Hypothesis: disease prevalence in high altitude is more than low altitude. I must do this in ArcGIS 10 and ...
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30 views

Problem with adding mosaic layer via arcpy

I have a mosaic layer that I want to add to my map in ArcMap. When I add this layer manually (i.e the "Add Data" button), a raster image, a boundary, and a footprint are added to my table of contents. ...
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66 views

Raster Calculator

I have a slope dataset. How do I calculate the real surface area for this slope dataset using the raster calculator. This is the example I was given: orthogonal area of a raster cell in square ...
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Polygonize Missing Polygons

Polygonize is not capturing all of the pixels in an image that has been converted to 0s & 1s. The pics below show -original geotif -geotif recalculated to 0s & 1s -polygonize output As the ...
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Conservation International Hotspot Data

I am creating a Heat Map and need Conservation Internationals's Biodiversity Hotspot Data in GIS form. I have tried to find the data online, but have since been unable. Where would I be able to find ...
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53 views

R{raster} getValues(): error accessing values of large raster

I am getting the following, while extracting all values with: rs<-getValues(rster) Error in getRasterData(con, offset = offs, region.dim = reg, band = object at data@band): long vectors not ...
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116 views

How to view a raster in CartoDB?

What is the easiest way to view a raster in CartoDB? From the list of formats that you can upload into CartoDB, I noticed that .tif is available, so I've tried adding a GeoTIFF, but it says that ...
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Weekly raster data for temperature and precipitation in US

I am looking for weekly raster data for US for temperature and precipitation. All the major datasets PRISM, WorldClim etc. are either on a monthly scale or daily scale. I was wondering if anyone has ...
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35 views

How can I preserve image quality when combining aerials of different resolutions?

I have two different rasters that were flown at different times during the same month. One has a resolution of 4-inches, the other has a resolution of 6-inches. Using ArcGIS tools, how can I combine ...
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70 views

Is there a Raster2pgsql GUI?

Has anyone ever attempted to create a raster2pgsql gui (like the shp2pgsql gui). As I am sometimes lazy to use command line, this could be a very nice to have.
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41 views

MapServer: UV_ANGLE not calculated correctly?

I'm following this example given on the MapServer website. But the angle of the raster is incorrect: The data is my grib files is correct, and should not yield these perfect opposite directions. ...
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55 views

PostGIS raster connection is not closed by MapServer

I'm using PostGIS raster in MapServer like this: TYPE RASTER DATA "PG:port=6432 dbname='mydb' user='postgres' password='1234' schema='public' table='truemarble' mode='2'" PROCESSING ...
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42 views

Import raster to postgis and add a foreign key constraint

I use raster2pgsql to import raster files into a table with this command line: C:\Program Files\PostgreSQL\9.3\bin>raster2pgsql -s 4326 -M -F -a c:\temp\mun.tif public.basqui_raster | psql -U ...
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29 views

Finding the best way to prepare raster image for a function in R

I'd like to ask what is the best way to prepare big raster images in R to run a function on whole images. I have 30 tiff images with the size of ncol=12648, nrow=4144. I read them in R separately. ...
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Fill holes with an area bigger of a specific value in a raster coverage

I want to fill some areas of a raster coverage with a value of my choice. Those areas now contain NODATA values. So, they look like holes in my coverage. I know I could use r.clump function of GRASS, ...
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40 views

ArcGIS 9.2 - Problem importing raster into geodatabase

When I try to import a raster (jpg or tiff) into a file geodatabase using ArcCatalog, MS Picture Manager opens and tries (unsuccessfully) to open RasterConversion.py located in my ArcGIS program files ...
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33 views

Analyse effect of groups on raster maps

I work with a mechanistic model that uses climate data to simulate some specific output for different time steps and spatial locations. Now I want to investigate the effect of different climate data ...
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111 views

Problem with polygon overlay in raster stats using gdal

I am using the raster_stats module in python to calculate the mean carbon value for different sets of polygons. Here is the code that I am using: africa_sat = ...
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94 views

How to create a circle vector layer with 12 sectors with Python and to save average value of underlying raster in each sector?

Hi I am writing a code with Python 2.7 using Arcpy 10.1 and I guess I am doing stuck with a silly problem that lies under my eyes. I have created a grid of points (with "Create fishnet" function) over ...
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213 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 ...
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108 views

How to use the raster calculator in the processing modeler of QGIS

I am trying to create a easy way to do raster analysis by building a model for two way raster calculations. I have two raster layers that I want to combine into a single raster. For now I've done this ...
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132 views

Precision for an FGDB raster dataset?

I would like to know the precision for an ArcGIS raster stored within a file geodatabase (FGDBR format); I can't seem to find this information anywhere in their documentation (apologies if I have ...
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60 views

Anyway to make Raster look like distinct Polygons

Is there any clever way to make a raster have a more clean vector look to it with straight polygon looking boundaries between classes when adding symbology to the data? Sure I could convert the ...
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47 views

Calculating Percent Overlap Between Distribution Maps

Hello there, I am currently trying to calculate the percent overlap (basically the total amount of overlap where these two species come into contact) between Lithobates catesbeiana (first image) ...
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158 views

Workflow with raster in Qgis 2.2

I'm trying to build a workflow with the Qgis 2.2 processing toolbox. I want to clip a raster layer with a vector layer using the GDAL tool "clip with a layer mask". But it doesn't work. The error ...
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78 views

How to use USGS Bulk Download on EC2 linux Server?

I am interesting in downloading Landsat 8 rasters to an Amazon EC2 instance and would like to know how to do it. I already install USGS Bulk Download but I do not know how to use it in terminal mode ...
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write rasters from estudm2spixdf with significant digits

I have estimated my kernels using kernelUD from the adehabitatHS package which produces information from multiple animals as a class estUDm. I am trying to write out from R to get into ArcGIS the ...
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Can I tell QGIS to load/show only a part of an image?

can I tell QGIS to load/show only a part of an image without to extract this region as an extra/ new image?
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QGIS 2.01 - raster transparency not working properly

I have loaded a color raster image (aerial orthoimagery) into a QGIS project. The layer is visible but very transparent (in the enclosed image the vector polygons are below the imagery), but when I ...
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46 views

Is there any GRASS command to measure the distance between a point in rastermap and another in vector map?

I have a question about WinGRASS 6.4.3. Is there any GRASS script command to measure the distance between a point in rastermap and another in vector map? I have a raster map and a vector map. Raster ...
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78 views

Extra row and column in a raster after GDAL grid import

I'm exporting an ESRI grid to TIFF format and after that I'm reading this exported raster file into SAGA GIS. However when Saga reads this file in there appears to be an additional row and column in ...
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200 views

ArcGIS Mosaic to New Raster() tool seems to interpolate data gaps on one computer/version but not another?

i have a group of raster files in .tif format that I want to mosaic together into one .tif. I've noticed that I get data gaps along the seams when I do Mosaic to New Raster() on my home computer ...
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175 views

QGIS 2.0 Problem with loading a Layer Style file that contains a transparent pixel list

I work with QGIS 2.0.1. For my raster file I have created a Layer Style with a transparent pixel list. When I import a rasterfile in a new project and load the layer-style file, the map changed to ...
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119 views

Fill tool creating large output files from sections of a Raster

(This raster information for one of the clipped rasters) I have a raster image representing a landscape that is about 1.3Gb. I clipped the raster into 31 sections which vary in size from 10Mb to ...
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78 views

Write raster with its attribute table and symbology

I am classifying lots of rasters and I'd like to automate the legend creation and symbology displaying for easy manipulation. Here is the kind of raster I'm dealing with: library(raster) r <- ...
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253 views

TIN to Raster Tool, output elevations are 3.40282e+038 and -3.40282e+038, tried calculate statistics didn't work

I have an input TIN file that I created using Create TIN. The elevations are all correct. When I convert the TIN to Raster using the tool, my output elevations are 3.40282e+038 and -3.40282e+038 ...
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90 views

Importing GPS coordinates to extract multiple DN values in ERDAS

I have a set of GPS points (stored as a csv for now) and would like to import these points to ERDAS to find the DN values associated with each location. I am able to import a SHP to ERDAS but the ...
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76 views

Qgis raster interpolation shift

Using Qgis 2.0.1, I'm attempting to interpolate a large point dataset (n > 400K) to a raster surface. I'm using the IDW option in Raster>> Interpolation>> Interpolation, and the resulting ...
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142 views

Why doesn't the mosaic to new raster tool or the mosaic tool work when I try to use them?

I am trying to mosaic 4 raster datasets of elevation together using the 'Mosaic to new raster' tool in ArcGIS 10.1. I have even tried using the 'mosaic' tool and it still doesn't work. The errors that ...
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82 views

Making spatial clusters by direct manipulation of raster pixel values using R

I think this is an overambitious million dollar question, but I'm always optimistic when I pose a question even though I feel like I left no stone unturned! I've processed a raster layer with pixel ...
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145 views

PostGIS Raster: raster2pgsql was not found in /usr/lib/postgresql/9.3/bin

I have installed sucessfully Postgresql-9.3-postgis on Ubuntu 12.04, following this instructions: http://trac.osgeo.org/postgis/wiki/UsersWikiPostGIS21UbuntuPGSQL93Apt Having done that, I have ...
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56 views

Color blending/compositing in web mapping frameworks?

The color/layer blending capabilities of QGIS 2 produce marvelous results. Blended rasters are especially nice to look at. Blending is, to me at least, a better way of combining layers than mucking ...
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Mann-Whitney U test for rasters

I'm doing a Mann-Whitney U test to compare two very large samples (sample size 1 = 13250; samlple size 2 = 38871) originating from a shapefile with 52121 features. I know t-tests are not recommended ...
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144 views

How to write script for Line of sight and Viewshed analysis in Global Mapper

I wanted to write script in Global Mapper for Line of Sight and Viewshed analysis. I tried to calculate using Viewshed and Global Mapper Tools but the issue I am facing is that analysis is user ...
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128 views

How to Iterate ModelBuilder for Zonal Statistics?

I want to use ModelBuilder to split a DEM into multiple tiles, then run the iterator on each tile made for the Zonal Statistics tool to find the highest point(s) in each tile and give these as an ...
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127 views

Why are the colors of my WMS layer messed up in QGIS?

I have a raster image on my computer, and I used it to test some geoserver features. (I'll upload images to show you what the problem looks like) I have the same raster, but transferred by wms. And ...