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

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Postgis Raster Unions Color Issues

Can someone explain to me what I am doing wrong here as I think I do not properly understand postgis raster bands. I have a set of geometries that I want to merge with a raster and created a raster ...
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1answer
17 views

Error reading Esri Grid format using GeoServer?

Using GDAL I can extract information from an ArcGRID raster, just by giving the name of the grid folder: gdalinfo -stats grid_folder All the statistics show up. I have tried with many arcGRID files ...
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19 views

Density slice/Colour slice in QGIS?

Can you do Raster Color Slices (like in ENVI) in QGIS? I.e. Where the histogram can be divided up into discrete units to represent different classes based on the values of the pixels.
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31 views

Rasterize line shapefile

I'm trying to convert a line shapefile to a raster image at QGis, but my attempts have been unsuccessful. I've tried to use Raster/Conversion/Rasterize and SAGA/Grid - gridding/Shapes to grid, but to ...
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ArcPy: Initialize zero valued grid Raster and iteratively increment

I'm jumping right into ArcPy to help out a friend who needs to automate some ArcGIS work. The problem at hand can be reduced to the following pseudocode: accumulationRaster = SomeZeroedRaster for ...
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19 views

GDAL WMS in QGIS 2.4

I'm trying to add in QGIS a layer shown here : propluvia When I watch in my console I see this request corresponding to the layer I need. The server is not able to respond to a getCapabilities ...
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21 views

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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1answer
36 views

Random-Forest Classification of 10cm Imagery for species-distribution in R (no point-shapes)

I'm actually trying to classify 10cm-resolution images with the RF-package. I do this to separate some species in the forest, seen on my images. While I was searching for an answer, I found the ...
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26 views

Error in polygonising raster data with QGIS on Mac

I'm using QGis Chugiak on a Mac and I'm trying to converting a raster layer in a vector data by: Raster/Conversion/Polygonize. So, I select the layer needed from the drop-down menu, I give a name to ...
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2answers
45 views

GDAL (Python) Aggregate Raster Into Lower Resolution

I have a (continent-scale) raster with 30m resolution in an Albers equal area projection. Each 30m cell has a value 1-34. I would like to aggregate information from this raster into a 1km grid such ...
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1answer
17 views

QGIS create raster from cadastre (property lot data) polygon

I have a cadastre (property lots) polygon dataset of a region. Have used rule-base style in QGIS to show different groups of properties in the dataset classified based on their property lot size (ie. ...
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1answer
38 views

Smoothing raster map

I have a raster map of US Midwest which is very sparse, i.e. the pixels of interest are few enough to be almost invisble when viewed at a scale where all states of US Midwest are visible. I would like ...
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1answer
45 views

Max cell value from a stacked raster

How can I find a max cell value from a stacked raster. Rmax <- maxValue(RAD1998.all[[1]]) works fine but Rmax <- maxValue(RAD1998.all[[2]]) gives NA. Of course not in a stacked raster. ...
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3answers
54 views

Scatterplot, correlation of dependence and r-square between two rasters

I have two rasters of the same region and of same resolution and I want to plot in a scatter plot their values and compute the best - fit line with r-square. Any idea how can I do this on Arcmap or ...
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1answer
29 views

How to crop a vector shapefile according to raster?

I am trying to clip a vector shapefile- points according to a DEM in QGIS. I used GDAL function and polygonized the DEM. Then I ran the Vector-Geoprocessing tools-clip in order to crop the vector data ...
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1answer
22 views

How to show number of patches in a neighbourhood?

Given one raster file containing only one zone that indicates patches of vegetation in a city and a shape file containing neighbourhoods for the city, explain how you could create a map that shows the ...
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2answers
30 views

Open Raster stored in ESRI V10.0 Geodatabase in QGIS V2.4

Is there a way to open a raster that is stored in ESRI V10.0 Geodatabase in QGIS V2.4. I can open the vector layer, but there does not seems to be a way to open a raster.
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1answer
25 views

Get min-max values of a raster and populate two parameters with the values in tool validation script

I am customizing the script tool behaviour of a custom script and would like to get the min-max values from a raster self.params[0] and populate the next two parameters, self.params[1] and ...
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2answers
31 views

Plot a Raster of Weather data in Leaflet JavaScript Map without generating server-side tiles?

I want to show different weather data I have as binary arrays on a server using leaflet. But I do not want to generate tiles on the server. For each point in an a array I have the coordinates in ...
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1answer
26 views

raster files are not exact in extent after clipping

My two layers (chlorophyll-a and Bathmetry) are not exact after I clip my rasters. My bathymetry data (1) is reporting up to 10 decimal places where as chlorophyll-a (2) is only 3 decimal places and ...
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1answer
46 views

How to overlay a county boundary on a raster file?

I want to overlay California county boundary top of raster layer. Here is is my code: data(coastsCoarse) data(countriesLow) library(gtools) library(maps) library(maptools) library(sp) # Raster ...
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1answer
32 views

Convert polyline to presence absence raster in arcpy

I have a polyline that I am converting to a raster in arcpy. This is occuring within a loop and at each iteration I change the processing environment to a different area of interest. In this case it ...
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24 views

Raster loaded in ArcMap 10.2.1 not showing decimal places for value

I have an IMG format raster that I am loading into ArcMap 10.2.1. The pixel type and depth, as reported by the Source tab in Layer Properties is 32-bit floating point. The values, as reported in the ...
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1answer
13 views

Placing a cost raster in Arcmap Table of Contents in 10.2.2

We have a set of routines that have been used for writing rasters to the ArcMap table of contents from our tools. The code that always worked is this: /// <summary> /// Used for ...
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calculate slope and aspect by uv image from 3d model [closed]

I created uv image from 3d model (building) in blender.My project is to calculate solar irradiation of building. For that, i need to calculate slope and aspect and also how to georeference uv image. ...
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2answers
52 views

Group adjacent polygons with similar (but not same) attributes

In ArcMap 10, I have a few dozen tiffs with cells that represent habitat area that has been burned. Each burned cell has a Julian date of the fire associated with it. I want to end up with polygons ...
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1answer
25 views

Extract all raster cells outside a polygon

How does one perform the very simple task of extracting all raster cell values outside a polygon? I've been looking through QGIS for hours with no solution to this simple problem.
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40 views

Problem loading output layer QGIS

Every time I run operations with temporary file output from the graphical modeler, I get the following error message: Oooops! The following output layers could not be open CLIP: ...
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1answer
21 views

Finding coordinates of the image corner

I have a .bmp image with a map. For creating image i used a Ingeo 4.4 and function MakeImage() What i know: Height an Width of bmp image dpi Map Scale Image Center's coordinates in meters. What i ...
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22 views

Save fails on raster object created from NumpyArrayToRaster [closed]

I am trying to save an ESRI grid built from a numpy array and am getting an error I've never seen before: Unhandled Exception: System.IO.FileNotFoundException: Could not load file or assembly ...
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1answer
40 views

SAGA raster calculator, ifelse command syntax problem?

I am trying to get the saga raster calculator in QGIS to spit out all values of a raster that are inferior to 10, and make all other values zero. I think the syntax is correct but I keep getting the ...
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2answers
34 views

Is there any efficient way to create a raster with pixel value representing a unique id calculated based on pixel lat/lon?

I have 10m raster for each state in US. Current pixel value represents something. I want to have 'same' raster but pixel size representing a unique id calculated based on pixel lat and lon. I am ...
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2answers
43 views

How are kappa and overall accuracy related with respect to thematic raster data?

I recently calculated kappa (using confusionMatrix{caret} in R) between a thematic raster dataset at 1m spatial resolution and another at 30m spatial resolution. I was interested in quantifying the ...
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12 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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2answers
107 views

How to generate wind direction raster using its U and V components in arcgis?

I have two raster layers representing the U and V components of a vector wind. I could generate the magnitude raster by applying (u*u+v*v) in Map Algebra in ArcGIS. Now I need to generate the ...
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1answer
105 views

QGIS GRASS Missing Dependancy

I want to perform a view shed analysis in QGIS using GRASS 7 r.viewshed. When I double click on r.viewshed in GRASS GIS 7 commands in the processing toolbox of QGIS I get the following message: ...
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1answer
17 views

Problem with batch mode Saga Raster Calculator

I have to do a couple of raster multiplications for which the batch mode would save me a lot of time. But the only thing I get are rasters that contain nothing but nan values. If I multiply the ...
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15 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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35 views

Levelplot(RasterVis) two marginal plot scale?

How can I add/display scale to two marginal plot? RAD1998.all <- stack(list.ras) list.files <- mixedsort(list.files(paste(getwd(), "/1998bil/", sep = ""), full.names = F, pattern = ...
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1answer
32 views

Deleting vector lines beyond image extents using QGIS?

I am using QGIS 2.2 I have one vector line layer (roads) that stretches beyond my base image (see below). I wish to have the roads "clipped/trimmed or deleted" right at the edge of the image's ...
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1answer
11 views

How can I shift raster layer for making cloud-shadow mask?

I want to make cloud shadow mask in QGIS. I have raster cloud mask and I have to shift it by X,Y coordinates. Is there any easy solution? Many thanks, Helena
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25 views

Graphically depict statistical difference between thematic rasters

The graph shows a regression between two raster datasets with classified tree canopy cover: class 1 = 0-10%, class 2 = 10 - 20% ...class 6 = >60% (Figure 1, Figure 2). The spatial resolution for ...
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splitting polygons by semi-automated classified raster and into multipolygons

I am studying glaciers. Most of them in my case are partly covered by debris (i.g rocks) and partly not. So I ran an automatic classification to recognize these two type of coverages and produced a ...
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1answer
44 views

levelplot index issue

levelplot with static index works fine but not in a for loop. What's wrong with my code? Static index: png(paste("1998",outlist[[1]],".png",sep="")) levelplot(RAD1998.all[[1:4]]) dev.off() ...
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1answer
42 views

R -plot 12 images per plot or save 12 images per image file in R

Here is R script and my question is How can I plot 12 images per plot or save 12 images per image file because I have total 864 images. RAD1998 <- raster(paste(getwd(), "/1998bil ...
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1answer
31 views

AttributeError: 'unicode' object has no attribute 'save'

I'm trying to multiply my raster to 100 from my ListRasters. I've adapted the code (especially the for loop portion) also from this site. Now, I'm encountering an error at the last line, when saving ...
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1answer
125 views

Highest DEM pixel in polygon

I'm working with QGIS and have a big DEM raster layer with height information and a vector layer with many polygons, representing 1 x 1 degree tiles. Now I want to find for every polygon the highest ...
2
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35 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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1answer
14 views

QGIS raster clip error: Cutline not of polygon type

I have a raster file and want to clip it, but I'm getting this error: "ERROR: Cutline not of polygon type" what does this error mean and how can I resolve it?
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19 views

Align & Sum Grids in Python

I have two grids. One, call it A, is 4320x2160 cells and spans the whole globe. The other, call it B is 8640x3432 and spans the circumference of the globe, but is clipped toward mid-latitudes. Both ...