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

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Performing unweighted overlay on multiple raster layers

Is there a simple process in ArcMap v10.2 that will allow me to overlay three raster images, whereby any obscured pixels will be deleted in the output file? I do not want to retain the values of any ...
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How to create raster from table containing cell values in PostGIS?

I am having a table with integer values. These values are in between 0 and 2. I want to create a raster out of that table with integers as cell values. Or else how to create polygons out of that table ...
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201 views

Spectral profile (z-profile) viewer for ArcGIS

I have multilayer raster with 6 bands. Is there a way to select one specific pixel and to display the z profile (the values of each band) for this pixel as a chart or table? I am looking for a tool ...
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13 views

QGIS clipper problem when mask used

I have encountered a problem with the raster>extraction>clipper function in QGIS when a mask layer is used. In the image below the diagram on the left shows part of the original raster. The diagram ...
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53 views

Merging rasters which overlap using ArcGIS for Desktop?

I need to merge two rasters which overlap, both indicate distance values. I need the output of the merge to result in the shorter/lower distance value. I am using ArcGIS 10.1. I hope it is more ...
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205 views

How to access raster NoData value?

I am trying to programmatically access the NoData value in a raster dataset as shown in the screenshot. Two tools that come to mind to describe raster properties do not seem to be able to describe ...
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2answers
723 views

Calculate area covered by a particular raster layer within polygons in QGIS

I am trying to extract information on vegetation cover within a set radius of point locations (my sites). I have succeeded in creating a new vector layer of circles with a 5 km radius around my sites. ...
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1answer
19 views

QGIS: Delete information from rasters and shapes that are out of country borders [duplicate]

I am trying to make topographic maps for some countries and show only those countries. I already created reliefs from SRTM-data and imported lake and river data from Natural Earth. Now I want to ...
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68 views

(How) can I write string data to a raster with Python/GDAL?

In Python, I have a NumPy array of string values (categories of some variable) that I'd like to write to a raster file (.tif or .img) using GDAL. The impression I get is that it's not possible to ...
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115 views

How do I mask a raster in TileMill?

I've tried just about every single TileMill compositing operation on the vector and raster layers in question, and I have to admit that I can't figure it out: How the heck can I mask a raster with a ...
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10 views

Panel plotting of raster images

I have never used panel plotting for raster images in TIFF format. Any ideas what would be a better module/library to panel plot raster images with examples?
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31 views

Can the maximum and minimum values of raster display be changed automatically when changing the data frame extents?

I have a raster layer in arcgis which covers a large surface area. I would like to be able to zoom into specific areas of this raster and have it display only the range of values in the area I have ...
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27 views

Rasterize gives weird image

ro<-readShapeSpatial("roads") ra<-readShapeSpatial("railways") co<-readShapeSpatial("LIE_adm0") u<-union(union(extent(ro),extent(ra)),extent(co)) rast<-raster(u,res=1) ...
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461 views

Histogram Matching Python

I am trying to do histogram matching using Python to improve the mosaicking process of multiple overlapping rasters. I am basing my code on that found at: ...
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2answers
24 views

Combine multiple binary rasters to a single raster

I have 5 different species richness maps which I am trying to join in order to show one cohesive map. Each species raster layer has values of 1 and 0; 1 if the species lives there and 0 if the species ...
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27 views

Determine value nearest to given coordinates

I'm new to GIS and have a very simple question. I have a raster that specifies the geographical distribution of temperature. I would like to find the temperature that is closest to a particular set of ...
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372 views

QGis Save Raster as Rendered Image

In QGIS 1.9.0 Master, when you right click on a raster in the Layers Panel and select "Save As", you can select the output mode to be "Raw Data" or "Renedered Image". When selecting the Rendered ...
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23 views

Landsat Data to Map Slums in India

I am working on a project to answer the following geographic question: How much have slum areas increased in Mumbai, India, since the 1970's (or earliest data). I have downloaded LandSat imagery and ...
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1answer
23 views

Mosaic to new raster: same number of bands issue

I am trying to mosaic 32 raster files (min value 0, max value 13) into one raster file so that I can later use this new raster to extract multiple values to points. However, when I try and mosaic the ...
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28 views

QGIS error when importing .asc LIDAR data

First let me say that I am novice in GIS department. As archaeologist I had only some courses 8 years back when i was still studying. Now, the problem: When I try to import .asc as raster layer I ...
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99 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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1answer
230 views

ArcGIS model builder: How to reclassify 16,000+ rasters and do weighted sums on these rasters per year?

I've been trying to build a model in model builder (ArcGIS 10.1) which can do the following task: I have a folder full of ca. 16,000 raster files (.asc) representing mean temperatures for each day ...
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35 views

creating a random gdal raster with random predefined values

So far I have developed the below code but for some reason it only works for say one class of landuse instead of two. Would you please tell me where I have gone wrong? Thanks so much import os, ...
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6k views

How to get raster image as array in Python with ArcGIS

When starting to work with Python and ArcGIS 9.3, I assumed there would be a simple way to get a raster image into a Python array so that I can manipulate it before storing it back as another raster ...
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31 views

How to avoid “Unable to compute a transformation between pixel/line”?

I am trying to re-project from Equi-rectangular to the NASA global EASE grid (Equal Area Scalable Earth) grid 1383 586 with a ~25 km cylindrical projection (ESPG=3410). The file is provided as HDF5. ...
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21 views

Where to find QGIS geoprocessing results?

Is there a way to access in QGIS 2.6.1 something like the Geoprocessing Results window found in ArcGIS? The History and Log window in QGIS appears to show the geoprocessing results from SAGA, OTB ...
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41 views

Extract values from raster by using polygons

I am working with multiple raster files that cover all of united states. The file format of the rasters - GeoTIFF. I have around 100 geotiffs that I need to process. Then I have another shapefile with ...
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271 views

Creating planes, eg roof surfaces, from LiDAR/DSM data

I am capturing the area of roof tops of buildings from a DSM (derived from LiDAR data) which has not been much of a problem. I can then also derive angle, hillshade and aspect but it is only ...
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23 views

Clipping rasters

We are clipping one raster to another and our teacher gave us this hint for the 2nd parameter "Remember that the Describe function returns an object. The Clip tool will need the string representation ...
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2answers
46 views

How to compute layer by layer after stack?

I have some rasters that I want to compute the moving average and then rewrite the rasters again. r1 <- r2 <- r3 <- r4 <- r5 <- r6 <- raster(nrows=10, ncols=10); r1 <- ...
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2answers
899 views

How can I calculate the vertical distance to the nearest water?

Summary: I would like to create a raster where each cell contains the vertical distance to the nearest water (a decent approximation would be acceptable). The problem is that I'm not sure how to go ...
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2answers
1k views

Zonal Statistics as table creates output but some are Null

I have temperature as a raster file and different ecoregions of a province as polygons. What I want to do is calculate the mean temperature per ecoregion. I succeeded in doing this by Zonal ...
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351 views

Selecting raster values at random locations in a raster in python/arcgis

I have a large dataset of integer rasters, and was hoping to find a way to generate a "random" selection of pixels for four of the rasters, while making sure all 5 classes, which I've specified based ...
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16 views

Querying Raster Dataset by Location to Study Area

I have downloaded a very handy raster dataset generated by the Nature Conservancy for identifying terrestrial habitat cover types in the north east. Link to the project info and a link containing a ...
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36 views

Term for combined Raster and Vector data [on hold]

Is there a GIS term for a single feature that contains both Raster and Vector data? IE: A topographic shaded relief raster that also contains the vector elevation data? I am working with GRID data ...
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QGIS - r.* commands not found

I'm very new to GIS and have recently installed QGIS on my mac desktop computer, running Yosemite 10.10. I'm working with DEM data for stream network extraction, but the majority of grass raster ...
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How can I convert data in the form of lat, lon, value into a raster file using R?

I have a data set of values over a km grid in the continental U.S. The columns are "latitude", "longitude", and "observation", e.g.: "lat" "lon" "yield" 25.567 -120.347 3.6 25.832 ...
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24 views

multiply a rang of values in a floating raster to a constant

I have a floating raster layer. I want to multiply a rang of its values to a constant. So, I used the "Con" tool in map algebra with the following script. Con(("Extract_rast1" >= 0) & ...
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How to OCR topographic maps

I have old topographic maps that i have scanned and converted into pdf in Actobat XI 11. I need this pdf to be text-searchable (not mere image). To do this i tried text recognition in acrobat but it ...
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How to re-grid a raster using area-overlap weighted averaging?

I have two rasters r and r2 with different resolutions. I want to re-sample (re-grid) r2 to be the same as r using area-overlap weighted averaging:If an r grid cell is covered by more than 1 ...
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29 views

Importing raster from ArcMap to Adobe?

I am currently working with 3 data frames in ArcMap. I exported them to pdf then Adobe Illustrator. I noticed that 2 of the data frames that include rasters come up with striped layers on them (while ...
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QGIS - quickly style categorical map

Example situation: a raster map that denotes various provinces in a country, each indicated with a unique value. Goal/question: quickly (for 'preview' purposes, not making a publishable map) assign ...
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3k views

How to exclude missing values from raster layer?

In my raster layers the value -999 means "missing". Those points completely mess up any colormap in qgis because qgis treats them as normal values and includes them in the classification. I would ...
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1answer
23 views

How to export georeferenced Raster layer using QGIS2Leaf Plugin?

I got excellent results while exporting vector layer with styling through qgis2leaf plugin. Whereas when I try to do the same with a geo-referenced raster file (geotiff) which has a projection of ...
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1answer
999 views

How to Calculate Utilization Distribution Overlap Index (UDOI) in ArcGIS Desktop?

I was wondering if any of you happen to have any information on how to calculate the Utilization Distribution Overlap Index (UDOI) in ArcGIS 10? If I understand it correctly the UDOI takes two kernel ...
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30 views

Clipping raster out of polygon using ArcGIS Desktop?

I'm kind of a noob to the GIS programs, and I'm trying to create a map in ArcMap 10. I have a polygon which I manually created in Google Earth and then imported to ArcMap with the KML-Layer tool). I ...
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22 views

How to add a plot with a different x axis to an existing plot?

I am plotting a raster but I want combine to things in the same plot but in two different axis. library (raster) r <- raster(nrows=10, ncols=10);r <- setValues(r, 1:ncell(r)) extent(r) = ...
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9 views

merge rasters using mosaic to new raster - wrong output

I am attempting to merge two raster datasets into one output dataset. I am using the Mosaic to New Raster tool. Unfortunately, the output does not display the same categories as the original input ...
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2answers
692 views

Clip_management to raster extent outputs larger raster than raster extent

Using Python and ArcMap 10.0 SP5, I'm trying to reproject and clip a large input raster to exactly the same grid as a smaller target raster (same extent, pixel sizes and projection). The problem is ...
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Questions on raster math using ArcObjects

BACKGROUND INFORMATION: I'm using the 10.2 .NET API and what we are doing is this: I have a boat moving on the water at a cruising speed of 30 nm/hr. (and we don't care about currents affecting the ...