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

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766 views

Why does CON statement give ERROR 010240: Could not save raster dataset to (value) with output format GRID?

I am receiving the following error when trying to run the following code: import arcpy from arcpy import env from arcpy.sa import * arcpy.CheckOutExtension = "Spatial" env.workspace = ...
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2k views

ArcPy findAndReplaceWorkspacePath not working with Raster Datasets

Situation: I am working on creating a Python script that will replace workspace paths for every layer in a map document in order to fix broken layers after a data migration. The script works except ...
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394 views

“dataset does not exist or is not supported” using large GRID raster

I am trying my hand at arcpy for the first time to create a conditional raster from a set of threshold values. I have 3 large GRID format rasters (mos_zb3, mos_zb4, pca_finb2) I am trying to feed into ...
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108 views

QGIS proximity raster with extent beyond original coverage?

I need a raster coverage of distances from points outside the geographic region of interest, and am having trouble doing this with QGIS. Questions like this one (Calculating distance to points in ...
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2answers
180 views

Grass GIS 6.4.3, How to create a .PTS file

I'm trying to export a raster map in order to use it in the Flo-2d program. This program needs a .pts DTM file, do you know how I can create it? Alternatively, I can use a XYZ file looking like this ...
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2answers
3k views

Loading PostGIS raster layer into QGIS

I am unable to load a PostGIS raster layer into QGIS. I have looked through previous posts Loading raster from PostGIS DB into QGIS and Cannot add the PostGIS raster layer with QGIS but was not able ...
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51 views

Wrong pixel sums within buffers in Esri ArcGIS 10.0

I have a raster of Zambia, 100m² resolution (about 650mb). Buffers (single) at 1,2,3,4,5,10,15,20,25,30,50 km. I'm running "zonal statistics as table" in the model builder for all buffers (actually, ...
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330 views

Saga Reclassify grid problem

I am using Qgis 2.1 ver. 5f5cd4c (64 bit version on win7 64) OSGeo installed. I was trying to reclassify a DEM in EPSG:32614. I used the SAGA's Reclassify algorithm in the processing toolbox. I ...
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1answer
160 views

Create a band mask based on pixel locations, not in pixel values

I have this image loaded in QGIS, with two possible values for the pixels: 1 = orange, 2 = blue For simplification, assume it represents a province of a country. I want to extract just the part of ...
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317 views

netCDF-java has trouble reading this netCDF file(format) and fetching values from the latlon dimension

I'm developing an application where I need to extract variable-values from netCDF files. I'm processing several different formatted netCDF files and now one format seems to be creating some issues. ...
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180 views

QGIS Grass Plugin fails with r.cost.vect

I tried the following in QGIS with the Grass Plugin: r.cost input=preCostSurface@albi start_points=OSMroads@albi output=cost0109 max_cost=0 And I get the following error: Dev note: Adapted sites ...
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2answers
129 views

Count the area of rasterdata in specific shapefile polygons (residential density in different districts)

I'd like to count the exact area of three different residential classes (low, medium, high) by district of a shapefile which contains 225 districts. like: district 1 has: XXX sqm low, XXX sqm medium, ...
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1answer
850 views

Map Algebra - Grass GIS (r.mapcalc) merge two raster with NoData value

I have a slope raster and a road raster. The black pixels in the road raster are NoData values and the pink pixels have a value of 1. They don't cover exactly the same area. I want to create a new ...
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59 views

Selecting a bounded area within a raster

I am new to postgresql. I have imported a 256kb sample raster (.tiff) into postgres with tilesize 100x100. Now I need to select the area (rectangle) from the center of the image using sql query. Then ...
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94 views

How to use Plus tool in ModelBuilder?

I want to have the sum of at least 2000 raster combined to one raster layer using ModelBuilder (Plus tool). I think I'm missing something here. This model does not work.
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1answer
120 views

How to display NoData of a raster in QGIS

How can I show raster pixels with NoData value in QGIS? In ArcMap there is a button to choose the color for the NoData value. Is there something like this in QGIS?
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4answers
138 views

Is there any free resource to get international raster data (other than USGS)?

I am looking for any raster database that allows free downloads of any kind of raster data pertaining to Damascus, Syria and the surrounding Turkey area. I'm trying to avoid USGS since it requires a ...
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1answer
212 views

How to multiply raster DEM with a linear graph value

I would like to multiply my Raster DEM with a linear graph value y = mx + C. The graph values look as follows: I want to make a new raster where each cell will represent a damage factor from ...
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28 views

calculating mean and standard deviation for raster values using whole pixels within a polygon [duplicate]

i have a raster image and a corresponding shape file. i would like to calculate the statistics of the values within polygons which have a common attribute but only using pixels which are fully ...
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34 views

Layers and variables are not coming out in the raster calculator tool window

I have many shapefiles in the table of content but layers and variables are not coming out in the raster calculator tool window. I placed the cursor the left of the Raster Calculator window, dragged ...
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1answer
527 views

NOAA Nautical Charts .bsb format

Is it possible to load a nautical chart from NOAA into QGIS that has the .bsb format? Didn't have much luck with mrSID format. using QGIS(dev) on ubuntu 13.04
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2k views

How to access each raster in a stack with a loop

I have a stack of rasters and I want to access each layer, combine each later with another file and finally export the resulting file as a csv file. Is there any way to do this with a loop? So far I ...
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1answer
293 views

Import raster into ArcGIS

I received raster data from a grid of 1100 by 1000 meters with a resolution of 1 meter. It is the output of EFC-400 software showing the field strength around power lines. The data is currently in ...
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1answer
450 views

Understanding percentage drop-raster (flow direction-tool)

I'm creating a Topographic Wetness Index using a python script (http://arcscripts.esri.com/details.asp?dbid=16750) As I don't want this just to be a blackbox, I'm trying to understand the different ...
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1answer
891 views

Extract Raster Values by Polyline End Points

I am looking for a way to extract elevations of end points for line data in ArcMap 10.2. I have a road dataset that I want to use as a Network Dataset in Network Analyst. I want to be able to set the ...
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191 views

filling up a depression to create new surface

A collegue here has a problem I cannot help with. She has the surface (as raster) of a landslide release area (from AFTER the slide) and wants to calculate the calculate the theoretical/approximate ...
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1answer
453 views

How can I dynamically trim the informational border off of FAA sectional raster charts?

I'm trying to write a script that can automatically use GDAL to crop the informational border from the FAA's published sectional charts (GeoTIFF) found here: I know that I can use gdal_translate ...
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96 views

Sending Raster File in ArcMap, Attributes Gone

On my computer, I opened a .tif file in ArcMap 10.1 and reclassed the values into two categories - this results in a new file. I then send that file to another computer and open it in ArcMap but ...
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350 views

The fastest way of generating tiles from raster?

I have some MODIS imagery 250m resolution covering a large area which I generate tiles from using Mapnik and generate_tiles.py script. I need to run this script every day with new satellite images, ...
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194 views

Problem with merging 15 DEM files in ArcGIS

I have 15 DEM files downloaded from USGS website. The pixel depth of each file is 32 bit floating, generic with format FLT. I'm then using data Management Tools > Raster dataset > Mosaics to new ...
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1answer
146 views

How to work with 16 GB orthophoto raster

I would like to use one GeoTIFF raster in a custom ArcGIS-Engine Application, but my provider gave me 4 orthophotos GeoTIFF 4 GB each, because GeoTIFF is limited to 4 GB. Is there any other way to ...
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59 views

Selecting a rectangle box from a raster tiled table in PostGis 2.1

I am new to PostGIS as well as SQL queries for rasters. I have imported a raster .tif file into PostGIS with tiles. I would need to select a bounded rectangle from within this raster using SQL ...
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204 views

GDAL and Python: How to “pad the extent” or otherwise handle band.ReadRaster() for area falling slightly outside the image bounds?

In a nutshell, I'm trying to create a bare-metal tiling utility using GDAL and Python. As you can see in the graphic below, which shows the perimeter of a raster and the OSM-structured tile index, ...
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1answer
70 views

Calculating statistics for an Image Service

I haven't been able to find much information at all in regards to ArcGIS 10.1 Function Template Chains... I need to be able to load a .rft in my image service and calculate statistics... so I am using ...
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2answers
459 views

How to solve jpeg2000, jp2. crash & errors on arcgis 9.3.1 windows 7 64-bit

I have several problems at work. One is that jpeg2000 crashes ArcMap but mostly ArcCatalog when trying to read them. This is only occurs on machines with Windows 7 64-bit (we don't have Windows 7 ...
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2answers
1k views

Is there a Focal Statistics (spatial analyst) tool in ArcGIS equivalent in QGIS?

I'm attempting to use QGIS v2.0.1 to accomplish the same tasks that I can do using ArcMap v10.1 and I'm running into some trouble finding equivalent tools. In ArcMap I am using the Focal Statistics ...
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3answers
2k views

Best way to clip a large raster ECW file ?

I am trying to clip a large ECW (details below) but the raster file is too big to be processed entirely. Some details of the ECW below Driver: ECW/ERDAS Compressed Wavelets (SDK 5.0) file size: ...
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5answers
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Impossible to sum rasters because of nodata pixels

I have a set of rasters (.vrt) with daily soil moisture data. I want to sum the pixels of all rasters in order to have a measure by month. However, the whole world is not covered each day, which ...
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172 views

Interpolating shapefile of points to grid using Java?

I am looking for a method/prog/library(java) to interpolate points from a shapefile to a grid (file). I have seen arcgis can do that but i am looking for something free. More specific: i have ...
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4answers
2k views

How can I Destripe Landsat Images?

I am working with Landsat 7 ETM+ SRC-off imagery. I'm doing some land-cover classification for a place in Kenya. My problem is the no-data stripes in the image. Is there a way in which I can ...
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1answer
167 views

Raster Smoothing python [duplicate]

I want to perform raster smoothing on a DEM file. I want to to assign the elevation of each pixel using the average elevations of its 8 neighbors. The ESRI's "Python scripting for ArcGIS" has a ...
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2answers
404 views

Partial Map Pixel Projections

I have the following: A PNG or JPG of a random width and height, in pixels, that represents a partial map of the world (i.e. a rectangle of the United States). The four corners of this image are ...
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1answer
148 views

Problem loading raster QGIS 2.0

I am very new at GIS. I am trying to load a raster so that I can complete a tutorial on georeferencing. The raster file is a jpeg. However, whenever I try to load the raster, it gives me solid colored ...
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374 views

Finding coordinates from a nested grid as a numpy array

So this is a pretty basic question, but I'm trying to figure it out. I've written a script that allows a user to read in a raster and provide a cell resolution, and outputs the amount of cells ...
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152 views

raster to ascii in QGIS

I have a raster file (DEM or .tif), but I need to transform it into a .txt file (ascii). How can I do this in QGis (Quantum Gis)? Thank you so much!
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314 views

Calculating Z-scores in Arc

I am trying to take the natural log and then calculate z-scores on cell values in several composite band GRID rasters in Arc. I am not fluent in python and do not see a way to automate this within Arc ...
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894 views

Sum many netCDF rasters

For the first time, I am using NetCDF data files containing daily data about soil moisture at a global level. I want to be able to obtain monthly mean value of soil moisture for each grid cell. ...
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519 views

Extract values from raster based on weighted average area using polygon grid

EDIT: I am using Armap 10 sp 5 I have found similar questions but they were either unanswered or somewhat different to what I am asking. I have a raster with cell values 1-5 and a polygon shape file ...
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1answer
3k views

How to open a “Raster Dataset” in QGIS

I want to open a "Raster Dataset" in QGIS. In ArcMAP I can just add it like shown in the Screenshot (only the raster shows up). If I am trying to do this in QGIS. However there I don't see the ...
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1answer
691 views

How to join 2D polylines and DEM into 3D polylines?

I got a simple question but could not find a satisfactory answer yet: I have a road network in 2D/PostGIS and a DEM. I want to turn the road network into 3D by retrieving the Z-value from the DEM. ...