Questions tagged [zonal-statistics]

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).

Filter by
Sorted by
Tagged with
1
vote
1answer
67 views

Applying processing extent in zonal statistics

I am using Zonal Statistics to calculate statistics of a raster (input value raster) within land cover types which is specified by another raster (input raster). Both the Input raster and Input value ...
5
votes
1answer
102 views

Zonal statistics - computation time issue with assigning zones

I would like to upscale a 1/360 degree resolution raster (64800 x 129600) to a 1/12 resolution raster (2160 x 4320) by assigning to each cell in the low-res raster the number of cells in the high-res ...
1
vote
1answer
458 views

Polygons too Small for Zonal Statistics

In ArcMap, Zonal Statistics uses the centre points of the Rasters pixels to link to the under or overlying polygons. Some of the polygons that I am using are small enough that they do not overlap ...
3
votes
1answer
212 views

Improve the processing time of model using zonal statistics and raster calculations

I've built a model in arcgis 10.5 ModelBuilder to represent a process that I need to run for thousands of polygons and input raster combinations. The problem is that to this model, for one polygon, ...
3
votes
1answer
1k views

COUNT vs. SUM field of zonal statistics as table output table

I want the count of the number of raster pixels within that polygon. I ran the Zonal Statistics as Table tool using one polygon as the feature zone data and only getting the SUM. I thought it would ...
1
vote
1answer
25 views

Assigning value to point feature class based on count of cells with certain raster values?

I have a point feature class that I would like to assign a new field based on the neighborhood of a raster layer. I'd like to count the number of cells within that neighborhood and write that count ...
1
vote
1answer
66 views

Zonal statistics mean VS Field statistics mean in ArcGIS

I calculated mean from a raster for a single polygon using zonal statistics as table tool and got the mean as 440,000. The raster is the exact same shape as the polygon (used extract by mask tool ...
1
vote
0answers
77 views

Missing Observations in Zonal Statistics Tool

I am using zonal statistical tools. I have field boundary shapefile which has 1,062,063 observations. I am using zonal statistical as table tool to obtain precipitation values from raster layer. ...
3
votes
1answer
296 views

Zonal Statistics vs. Focal Statistics for GPS points

I have 200 gps points. I want to calculate total population living within a 5 km radius of the GPS point. I have a input raster for population. What is the most efficient way to make these ...
1
vote
0answers
187 views

How to query raster data using a polygon in a web environment

I'm struggling with the following; I am setting up a web mapping environment using Leaflet. In the front end I use Javascript and the back-end is build with Python. When clicking or drawing an shape ...
2
votes
1answer
423 views

Zonal statistics for several rasters in ArcGIS

I am running this Zonal Statistics as a Table code for a single raster and it works: import arcpy, os destination_path= r'\\Mac\Home\Desktop\arc_stuff' shapefile= r'\\Mac\Home\Desktop\arc_stuff\...
1
vote
0answers
103 views

Using zonal stats on lidar data returns unusual values [closed]

I have a raster of tree heights from Lidar and a polygon layer where I have sketched the tree crowns by eye from an orthophoto. See screenshot. I want to get the maximum heights within each tree ...
-1
votes
1answer
219 views

Raster processing and query PostGIS [closed]

I have around 2000 raster file in TIFF format of 4.5Gb size. I want to store them in a PostGIS DB in order to do some mapalgebra operation between them and than query the results of the calculation ...
7
votes
2answers
453 views

Is there an open-source equivalent of ArcGIS “Zonal Statistics as Table” tool?

With ArcGIS zonal statistics as a table I can easily calculate the mean value from a raster contained within a polygon from a shapefile. I now have a Mac, and therefore I cannot access ArcGIS anymore. ...
3
votes
1answer
199 views

Appending 10,000 tables using ArcPy?

I am trying to append ~10,000 tables together using an ArcPy script. I believe the method I am using does not work as the script is attempting to append too many tables at the same time. Would a ...
3
votes
2answers
169 views

Expected result for ZonalStatisticsAsTable MEAN Statistic Type?

I'm getting different results when using the ZonalStatisticsAsTable tool in 10.4.1 when compared to earlier versions (10.2 and 10.3). ArcGIS 10.2: ArcGIS 10.3: But in ArcGIS 10.4.1, the same data ...
0
votes
1answer
73 views

How to assign numerical value to polygons?

I have a shapefile of polygons, and a list of mean values of the area in each polygon. I need to assign said mean values to each polygon. How would I go about this using GDAL/OGR in Python?
1
vote
1answer
3k views

Zonal Statistics of a polygon and assigning mean value to the polygon [closed]

I have a large shapefile filled with polygons, and a raster of that same area. I need to use Zonal statistics to find the mean value of the area under each polygon and then assign that value to the ...
0
votes
1answer
353 views

Zonal Statistics does not calculate mean for all Features in the shapefile

This is a follow up question from: Python Script Zonal Stats as Table Loop Question I was able to get the script working successfully, but I'm running into a problem where zonal statistics is not ...
1
vote
1answer
1k views

Python Script Zonal Stats as Table Loop Question

I'm trying to write a small script loop script which retrieves rasters from each folder, performs zonal statistics using watershed polygons and saves it as a table. I've written similar loop scripts, ...
2
votes
2answers
4k views

Extract raster value into polygon

I have the raster map of monthly precipitation of some years (download from CGIAR http://www.cgiar-csi.org/data/uea-cru-ts-v3-10-01-historic-climate-database) and I need the mean values on a specific ...
1
vote
0answers
79 views

How to Remove No Data from a NetCDF Raster Layers?

Question: How to remove no data from a NetCDF Raster Layer? I am trying to use the Zonal Statistics as Table tool in ArcGIS to calculate the mean. The problem is I am not getting the correct mean, ...
0
votes
1answer
590 views

Calculating first quartile of a raster by zonal statistics?

I want to calculate the 1st quartile (25th percentile) of a raster (beneath polygons) using zonal statistics but it does not this option. Zonal statistics has: MIN, MAX, MEAN, MAJORITY, RANGE, and ...
1
vote
0answers
568 views

Extract mean raster values by fishnet in ArcGIS [closed]

I have a raster of 0.25m resolution. I created a fishnet with 100*100 m in ArcGIS. I want to extract mean values of the raster from fishnet squares(100*100). I tried zonal statistics in ARC but does ...
6
votes
3answers
766 views

Wrong min value from ArcGIS 10.4 zonal statistics as table

I used the zonal statistics as table tool in ArcGIS10.4 to calculate SRTM, the in_zone is a gridded shapefile, the in_value_Raster is the SRTM extracted for the region as in the image (90m x90m). The ...
3
votes
0answers
59 views

Zonal Statistics calculator differences between QGIS Lyon and Wien

I am trying to implement a process that uses the Zonal Statistics menu function. In Lyon, the menu that pops up had a field with a list of calculations, each with a check box. Here you can select what ...
1
vote
1answer
537 views

Writing geoJson from rasterstats

How would I write a proper geoJson, readable by a GIS, from the results of the rasterstats package? stats = zonal_stats("somePolygons.shp", "someTif.tif", ...
1
vote
2answers
259 views

Statistical properties of raster image

I want to calculate the mean and standard deviation of a raster image. In QGIS zonal statistics, we can calculate it within a polygon or a vector. But I want to calculate for the whole image. In ...
1
vote
1answer
193 views

Zonal Statistics ArcMap 10.4

I have a problem using Zonal statistics in python using ArcMap 10.4. This is a completely random error, and I have no idea what to do. Some back ground is that I have been running a script doing ...
0
votes
1answer
49 views

Problems when Joining table to polygon

In ArcGIS 10, I have several maps describing both habitat characteristics and climate. I also have a raster map of presence/absence for a species that I wish to examine using my other maps. All my ...
0
votes
1answer
263 views

Missing buffer values when using zonal statistics in ArcGIS Desktop?

I am using zonal statistics in ArcGis 10.2.2 to calculate the mean value of fire frequency within 1km buffers. However, I have noticed that this is not being calculated for all of my sites. There are ...
0
votes
1answer
26 views

Passing a number between feature classes in ModelBuilder

I am looking at two non-overlapping polygon feature classes (let's call them Counties and Somewhereland; the latter feature class has only one record). I need to sum a certain field (let's call it ...
2
votes
2answers
60 views

Zonal sum not working?

I have a raster file for India which is a cropland map with following information: Columns and rows: 7015, 6582 Cell size: 0.0041666667, 0.0041666667 Each grid of this cropland has a value of ...
1
vote
0answers
48 views

Zonal Statistic Tool

In ArcGIS, I have a grid 5x5km (I have it both in vector and raster formats) I want to calculate, based on this grid, the zonal statistic (MEAN) of a raster 30x30m pixel size. The raster overlaps ...
1
vote
0answers
53 views

Selecting cells with values from DEM those are above specific value corresponding to each polygon?

i have a shapefile with 2000 polygons and a DEM. i want to calculate zonal mean for each polygon considering values from DEM which are above a particular value for each polygon. i want to it with ...
2
votes
1answer
273 views

Calculating total area overlapping specific raster DEM color interval whose boundaries are confined by another vector?

I know this sounds quite difficult, but maybe it isn't for you or at least it shouldn't if I explain it correctly. (I'm using QGIS 2.14) I'd like to know to calculate total area overlapping a ...
1
vote
1answer
1k views

Writing result of PyQGIS to shapefile

I try to perform some zonal statistics on a shape- and rasterfile and write the output to a completely new shapefile! import sys # where is the module sys.path.append("/Applications/QGIS.app/Contents/...
1
vote
1answer
155 views

Extract results from zonal statistics [closed]

I am trying to calculate mean slope in given polygons. I first interpolate my (x,y,z) data to create a raster file and use the terrain analysis tool to calculate slope. Then I use the zonal ...
1
vote
0answers
42 views

Zonal statistics query

I have two rasters (Hyrdological Soil Group (HSG) and Land Cover) and i'm trying to find the average HSG for each land cover type. The HSG raster contains the values 2,3 and 4 and there are 23 ...
2
votes
0answers
154 views

Median and Mode estimations in the QGIS Modeler?

I would like to know if there is anyway in which I can combine the available tools in QGIS in the Modeler to estimate median and mode values from a raster (DEM) using polygons. I know the zonal ...
0
votes
1answer
665 views

What is (if there's any) difference between MAUP and Edge Effect

I heard both the term MAUP and Edge Correction in association with Spatial Statistics, zoning/quadrats, demographics etc. Is there a difference between the two? What is the difference then?
1
vote
0answers
201 views

Calculating the spatial variance of well density? [closed]

I have wells as a point shapefile and have calculated the spatial density of these wells in 400+ basins (polygons) by dividing the number of wells in each basin (found by doing a spatial join) by the ...
1
vote
2answers
114 views

Converting data in table created by Zonal Statistics as Table tool back into raster file?

In arcGIS 10 I have worked on a number of raster files, from which I have created one large table by using the Zonal statistics as Table Tool. I have a result as shown below (I have more than 70,000 ...
1
vote
0answers
291 views

Resampling netcdf file?

What is the best way to change the cell size of a netcdf file, keeping it as netcdf? I have looked into ArcGIS and GDAL and have not found anything yet. I prefer to use python if a solution is ...
2
votes
1answer
97 views

What is the most efficient way to get a table or attribute table of a float raster?

I'm starting with a stretch point raster. Ultimately I want to get a mean value of values with larger zones and then rate the zonal mean stretching from 0-1 and output rank/zone to a table or layer ...
2
votes
1answer
418 views

Using zonal_stats with python in QGIS to calculate statistics for each image

I work with Python in QGIS, I want to calculate statistics for each image that I have with a specify shapefile and save result after, I tried to do like this: from rasterstats import zonal_stats ...
2
votes
1answer
453 views

How does ArcGIS calculate zonal statistics with partially overlapping zones?

I am trying to get zonal statistics in ArcGIS. My zone raster is a world map with zones defined as "provinces (such as the US states)," and the value inputs are temperature data for each "longitude*...
0
votes
2answers
332 views

ArcGIS tells me 'raster' isn't defined

I am trying to get zonal statistics for a set of geographical units for several years and I would like to get the output in one dbf table, where the rows mark the geographical units and each column is ...
1
vote
1answer
296 views

Changing default field Input Value Raster for Zonal Statistics as Table?

I have a raster in ArcGIS 10 with the following attribute table: When I try to use the tool Zonal Statistics as Table over some polygons, it calculates the statistics of the fields 'Value' and 'Count'...
2
votes
1answer
187 views

Zonal Statistics with very large mosaic in ArcGIS

I have the complete National Elevation Dataset from USGS in over 3000 ArcGrid files (coming to almost 190 GB), and a polygon shapefile of Colorado counties. I'm trying to use ArcMap Zonal Statistics ...