Zonal statistics summarize the values of one raster within the zones of another dataset (either raster or vector) and output the results as a raster (for a single statistic) or table (for multiple statistics).

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302 views

QGis Zonal Statistics Plugin NoData included in Calculations

I have been trying to use the QGIS zonal statistics plugin. My raster has a nodata value of -99999 and all other values are positive. After computing the mean zonal statistics there are a number of ...
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249 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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42 views

Does converting polygon to raster generate more accurate results from the Zonal Statistics in Arcgis 10.2

I have heard the following for Arcgis 9.1 and wonder whether it is still an issue in Arcgis 10.2. If so, should I convert the polygon into raster before dissolve or convert the dissolved polygon ...
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63 views

Zonal Statistics Freezing QGIS 2.2

Running on Windows; 8gb memory, 500gb HD, i5 cpu; Raster file: 250mb I am having a problem with zonal statistics advancing past 17%. I am trying to run statistics on a crop grown in certain counties. ...
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100 views

Zonal Statistics using Gdal and Python

I recently came across a loop_zonal_stats function by @ustroetz found here: Issue Trying to create Zonal Statistics using Gdal and Python.. I am using a (single) polygon shapefile and a raster file to ...
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42 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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63 views

Tabulate Area using GDAL and Numpy

How could I perform a Tabulate Area using GDAL and Numpy? I am trying to summarize how many pixels of each class in a Landcover raster are within each polygon of a Census Blocks shapefile. I've ...
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345 views

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

I'm interested in calculating the overlap of home ranges (=utilization distributions in my case) of a bird species using sighting coordinates. This article introduced UDOI as the best index for such ...
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235 views

How to use GRIB data in ArcGIS? (Zonal Stat as Table)

I am trying to calculate zonal stats as table with a python script for 45 .grib files from the ERA-40 Monthly Mean of Daily Mean database (http://data-portal.ecmwf.int/data/d/era40_moda/) for certain ...
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67 views

Batch Zonal Statistics to Spreadsheets?

I have a pretty immense amount of Zonal Statistics as Table computations to do, and would love to find a way to grab mean and variance values from the little .dbf tables ArcGIS creates and put them ...
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77 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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47 views

I want to determine the average rainfall for a cumulative watershed, where I only have the sub-watersheds defined

I have a polygon layer with sub-catchments (sub-watersheds) and a grid of rainfall. I have used the Zonal Stats as a table to calculate the average rainfall for each sub-catchment, but I now need to ...
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125 views

Multiple polygons and rasters for Zonal Statistics as table in ModelBuilder

I have a large number (>17,000) of raster image files that I am creating by iteration. I also have clipped out corresponding polygon files with identical names in a separate folder (maybe not ...
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101 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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215 views

How to use Zonal Stats as Table tool with in-line variable substitution

I have created a model to iterate a folder of 5 shapefiles to apply the Zonal Stats as Table tool to a raster. My output table is saved as table%i% so i'm expecting it produce 5 tables (table0, ...
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83 views

Reshape Matrix and perform Zonal Statistics in Matlab

I have 2 grids: 1) n by m - at 100m 2) n*10 by m *10 - at 10m. These grids cover the same area. I have to perform zonal statistics at scale of grid no.2. Cell value of grid no.1 is cumulative for ...
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174 views

Problems running zonal statistics - not all zones represented

I have been working on a Python script to automate the steps illustrated by whuber here:Create points around the edge of viewshed results I am trying to create a horizon graph illustrating the ...
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163 views

zonal statistics in Python crashes

I have a python script that works (it's worked for several other projects in the past and it worked for my current project initially). But whenever I run it, Python crashes sporadically. It would go ...
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706 views

Raster grid for zonal statistics in R

I have two raster layer, the first one r is my zonal mask as a raster grid, and I created as: ext <-extent(Yraster) r <- raster(nrows=32,ncols=32,ext) r[] <-(1:ncell(r)) and project it ...
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24 views

Overlaying Line (Vector) Layer on Raster Zones?

I will make my best attempt to clearly explain my problem. I am using ArcGIS 10 I have a raster layer with 3 values that make up zones. For the purpose of this example, lets say these zones are ...
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27 views

Zonal statistics vs. random points?

Using ArcGIS 10.1 for Desktop, I wish to model the relation between soil productivity (SP) and a number of independent variables such as, e.g., terrain elevation and slope. For this purpose, I am ...
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44 views

What does “unsupported bin funcion type” error in ERDAS mean?

I want to open a set of .img files in ERDAS which are output files of zonal statistic function in ARCGIS. Before running the function, all images can be opened in ERDAS. After calculating zonal mean, ...
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42 views

Why does it take so long to run zonal statistics?

QGIS 2.0 Windows 7 I have pulled agricultural data from NASS CDL in tiff format. I want to track where a certain crop has grown over the years. My intention was to use a county shapefile overlaid ...
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35 views

Convert raster_stats list output to array / csv file

I usually program in R, but recently I have started to use python for most of my spatial programming. My python skills are still limited, and please excuse the simplicity of the question. I am ...
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41 views

Zonal statistics won't work after re-projecting vector layer

I have qgis 2.0. I want to analyze raster information within a buffer of 30 miles around a vector layer of cities across the world. However, both the raster and the vector are in WGS84. I have no ...
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41 views

Zonal statistics returns wrong values in QGIS

I used zonal statistics for a simple task: to transmit raster pixel values to vectormap which contains squares as big as the pixel size is. The problem is that the values of the outcome are not ...
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90 views

Creating Cluster “Zones”

I've looked at the "Questions that may already have my answer" and it didn't appear that the questions were specific to my questions. Although I am sure I am not uncovering some brand new quetsion ...
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16 views

Get Descriptive Statistic by Geometry from ArcGIS Server Image Service

Image Services have a method called Compute Histogram which is akin to Tabulate Area in ArcGIS Desktop. Is there a method or raster function template method an Image Service can use to get ...
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59 views

Zonal statistic on recoded raster layer. Information about class value and quantity

i have a raster layer, with 15 different classes. In the raster layer are differrent classes, which stand for windspeed. Then i have a shp-file, where polygons represent urban regions or just free ...
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229 views

Tabulate area - Spatial Analyse

I am trying to calculate the amount (sqm) of land cover types (forest, water ect.) in 1045 buffer zones, all the same size (500m in diameter).. The buffer zones are polygons and the land cover is a ...