Spatial Analyst is a extension within ArcGIS that provides a range of spatial modeling and analysis tools.

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244 views

Tabulate Area ArcGIS

I am trying to work out the relationship between the 'processing cell size' and the result from Tabulate Areas. If one uses the same as the raster cell size, and this is the same for both rasters, the ...
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500 views

ArcGIS Kernel Density with polyline, search radius / bandwidth calculation

I'm conducting a density analysis of a series of polylines and I'm hung up on determining an appropriate search radius. The default calculation performed by arcgis is to take the shorter dimension ...
3
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45 views

Problem with Flow Direction in DEM

I have the following problem with Flow Direction Tool in my DEM and with such wrong calculated flow direction in the centre of DEM I am unable to delineate any watershed. What can I do?
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101 views

How to display the slopes that only facing west using ArcGIS for Desktop?

Here is what I am struggling with ... In ArcGIS for Desktop I have to Derive and symbolise areas considered susceptible to avalanche risk based on the following simple rules: areas with a slope ...
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30 views

Need to run a Groundwater Analysis Based on Points to a Raster

The title sounds daunting, but this task really isn't. I have well samples over a decade in certain locations through an area. These samples contain a value of that element at that point in time. I ...
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50 views

Elevation interpolation along a (sewer) line

Here's what I want to do. I have a vector sewer line feature class that contaings a field for the high invert elevation and one for the low invert elevation. I can turn them into a raster no problem ...
3
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28 views

3D distance and topography

I have a set of points and want to find out the nearest distance to a water body (poly lines) taking into account the terrain and get a surface distance calculation. I understand that the way is to ...
3
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117 views

Cost Path: multiple pairs of sources and destinations

I have seen many questions related to this problem but very few answers. I am very new to scripting and using ModelBuilder, but I am trying to calculate the cost path for 200 polygons with a single ...
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229 views

Determine 3 and 6 minute fire response times

I'm expecting to get an Excel file with data on previous fire and emergency response times. I was told it will have incident addresses and the response time for each incident (~ 12K incidents). I also ...
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61 views

arcpy adding time to Raster Mosiac Footprint

I am trying to create a raster mosiac for use in animating data over time. The current workflow is: Create .gdb (arcpy.CreateFileGDB_management) Create Raster Mosaic ...
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410 views

What is the convergence threshold for ArcGIS Iso Cluster?

The ArcGIS tool Iso Cluster Unsupervised Classification does not seem to have any documentation on the convergence threshold used in the tool. To compare, Erdas Imagine has all of the necessary ...
3
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124 views

Which geostatistical tools to use to determine surface changes over 40 years?

I have a data from the Weather station with SWEmax (snow water equivalent) collected over 40 years. I need to interpolate the data over my river's watershed and then, somehow, determine the ...
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720 views

Performing a Multicriteria Analysis Using Distance Along a Road Network

There is the possibility that I will be working on a project which will look at thousands of properties in a region and measure their accessibility to different services (schools, parks, hospitals, ...
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522 views

How to calculate Solar Radiation falling on vertical surfaces using DEMs and ArcGIS?

I am using ArcGIS10 Area Solar Radiation tool to calculate irradiation on horizontal surfaces (building roofs) but need to do the same for vertical surfaces (building facades). Any ideas on how to do ...
2
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0answers
56 views

How to use the multiprocessing module on python to execute a spatial join?

I have several shapefiles of the entire Amazon rainforest each with millions of polygons (they are fairly detailed and take some time to draw on ArcMap). I need each of these shapefiles to be ...
2
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0answers
107 views

Merge Raster Layers with Raster Calculator

I am looking to merge three raster layers together, we are only allowed to use the Raster Calculator tool in Spatial Analyst, ArcToolBox. Using ArcMap 10.2
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26 views

Characterizing territory according to its relief using ArcGIS Desktop?

I want to characterize the territory according to its relief with ArcGis 10. I'm trying to define a wide territory by its relief, but I would like to do it in an automatic or semiautomatic form with ...
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104 views

Comparing two kernel density rasters for areas of interest?

The background to my question is that I have unit sales for Product A aggregated by city. I also have unit sales for Category A aggregated by city. The goal is to compare areas where Product A ...
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69 views

Spatial Autocorrelation tool vs. Incremental Spatial Autocorrelation

When you run the Spatial Autocorrelation (Monrans I) tool, you have the option of setting 'Conceptualization of Spatial Relationships'. This option isn't available for the Incremental Spatial ...
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423 views

Cause of ExecuteError: ERROR 010067 from arcpy.sa.CostPath?

By using the code below that creates least-cost paths between several polygons, I obtain this error message: ExecuteError: ERROR 010067: Error in executing grid expression. Initalization failed ...
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57 views

ArcMap - proportion of polygon in lon/lat grid cells

I have a polygon representing a river basin on a 1 X 1 degree lat/lon grid. I need to create a boundary using the grid cells as the boundary to best represent the outline of the basin. I would like to ...
2
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183 views

Watershed delineation?

I'd like to delineate the catchments upstream of the sampling points. In order to do that, I have done the following: Burn the rivers into the DEM using ArcHydro>DEM Manipulation>DEM ...
2
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0answers
114 views

How to add flow arrows to groundwater table map?

After I had created groundwater table map, I tried using 3D Analyst>Steepest Path to add groundwater flow arrows to the map. However, it didn't work. Would you please let me know how can I add these ...
2
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62 views

Copying an entire column between layers (tables)

I have a raster layer with probabilities as values and I process them using the Spatial Analyst extension. After the processing the values are modified, however I would like to also have the original ...
2
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373 views

Problems with spatial autocorrelation in Geographically Weighted Regression (GWR) analysis

I have conducted an Ordinary Least Squares (OLS) and Geographically Weighted Regression (GWR) analysis in ArcGIS where I have tried to predict biodiversity patterns in an area. When I examine the ...
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377 views

Question related with NDVI value on water

There is a surreal thing on my NDVI images. NDVI values on lake is ranging from -0.04 to 0.7. (The lake surrounded by forest and has freshwater). Theoretically, negative value of NDVI is correspond to ...
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164 views

Different results from Spatial Analyst GP Tool and Python

I am writing a script that has to subtract one raster from another. The rasters I have represent 1) Parking Lots (1 = Parking Lot, 0 = not Parking Lot) and 2) a buffer around the Parking Lot (1 = ...
2
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179 views

ArcMAP path distance function handling of polygon and raster inputs

I am using a path distance function to calculate distances from a set of source cells on a land use raster. Unfortunately, my land use raster and my other inputs have different cell sizes. The land ...
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336 views

About zonal statistic function in ARCGIS

I calculated zonal statistic in Arcgis to get max/min value of each LC types. Broadly, LC image include forest, grassland, waterbody etc. But output max value of zonal statistic function give me 0.972 ...
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554 views

Output raster extents when using the Spatial Analyst Extract By Mask tool to clip a raster

I am using ArcGIS 9.2 and I have a simple python script that does the following : Loop over a polygon feature class (shown in red in the image below) For each record, create a feature layer to ...
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0answers
62 views

How do I make a path cross the most possible classes in a raster?

I want to create a function and possibly use Arcmap tools to create something similar to Cost Path. Instead of just choosing the LCP, it must cross through the most different integers. Let's say I ...
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635 views

Spatial Analyst Cell Statistics seems to give the wrong answer in ArcGIS 10.0

I have a script that calculates standard deviation for a list of grids using the Cell Statistics function in Spatial Analyst for ArcGIS 10.0 The syntax is this: stdevGrid = ...
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10 views

How to classify land cover with MMU 25hac

By using the 30 meter resolution of landsat TM & ETM+ data, I want to create the land use/ land cover map. I have read in several studies to first decide about the minimum mapping unit (MMU) that ...
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14 views

Clarification on a previous Utilization Distribution Overlap Index (UDOI) answer

I'm really struggling to calculate the Utilization Distribution Overlap Index (UDOI) and could really use some clarification on a previous answer. There is a comprehensive guide to what i am trying ...
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28 views

How legitimate is smoothing raster data that has been converted from polygons?

I am interested in applying this methodology to census block data after conversion from a raster: http://rutgerscps.weebly.com/uploads/2/7/3/7/27370595/censusdatasmoothing_brief.pdf Basically, the ...
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0answers
53 views

Is there PostGIS equivalent to arcpy.sa.Slice() function?

I have an existing system built on an 8.3 PostgreSQL database which uses a ArcGIS - Spatial Analyst for a couple of raster operations. The system is moving to PostgreSQL 9.2 and I'm evaluating if the ...
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17 views

Risk Maps - Spatial Analysis

I have created a basic mining subsidence likelihood map which contains the variables of depth and distance from lineament using the weighted overlay tool. From these results I would like to create a ...
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0answers
20 views

Weighted Overlay Decimal Values for Evaluation Scale

I would like to do a weighted overlay of different raster datasets. I would like my evaluation scale to be from 1 to 10 with 0.1 as the incremental value. This way for example a criteria could have ...
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0answers
70 views

Estimating parameters of a semivariogram?

I have got a shapefile of rain gauges with a field giving the precipitation amount in a particular day. I need to interpolate the precipitation values to obtain a precipitation map for a particular ...
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44 views

Assigning score to raster based on cell overlap with other raster and field value

I have a set of rasters that I've assigned scores to individually (scored based predominantly on values of other fields). The scoring scale is the same for all rasters, but the factors that determine ...
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28 views

Filtering for slope using kernel size in ArcGIS Desktop?

I have problem in smoothing the slope derived from digital elevation model. I want to do filter for the slope <5 degree in 7 X 7 kernel size, 5-20 degree in 5X5 kernel and >20 degree slope in 3X3 ...
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0answers
50 views

Calculate amount of rainfall per grid

I have precipitation measurement data of some points. I calculate the spatial distribution of rainfall using thiessen polygon method with ArcGIS. This shows amount of total rainfall on polygons. How ...
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0answers
58 views

Determining Euclidean Distance in Polygon using ArcGIS for Desktop?

I would like to ask about how to create an euclidean distance analysis from a polygon shapefile. I got a geology shapefile in which I want to create a "distance from geological boundary" analysis. ...
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0answers
132 views

How to perform a weighted overlay analysis with categorical classed data?

I have several land use layers (vector polygons) that all contain a field about land use in different classification systems and would like to combine them to a single classification. I would like to ...
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0answers
84 views

ArcGIS Solar Radiation tool says output global radiation raster empty?

I am using ArcGIS 10 with windows7 64 bit on core i7 processor I am working with ArcMap 10 solar radiation tool to create the area solar radiation map. Every time I run the tool it stops after some ...
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0answers
56 views

CostPath gives error for specific points?

I am using the tool CostPath. As an input feature destination data I've entered several points (no specific value, just distributed geographically), and as the cost distance raster I've entered the ...
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0answers
76 views

Error issues when using Cut Fill operation in ArcGis 10.2

I wonder if someone is able to assist with an issue I have about a series of errors I get when using the cut/fill tool in spatial analyst, ArcGis 10.2? Someone posted a question sometime last year ...
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0answers
44 views

how manage mysql spatial polygons in parent child style

I want to store location-polygon data in a parent-child relation. I am using spatial data in MySQL and Google map for polygon. Eg: World 1.1 US 1.2 China 1.3 Japan 1.4 South Africa 1.4.1 Pretoria ...
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33 views

Trying to combine 29 zip code service areas into 10 or fewer service areas

I am tasked with coming up with 10 or fewer zip code service areas based on 29 pre-existing zip code service areas. The zip codes cover 5 counties and many service areas, obviously, overlap. The ...
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174 views

How to extract NetCDF raster values to time enabled shapefiles?

Does anyone know a good way to extract NetCDF raster values to each data point from a time enabled shapefile at the correct time? I have tried using a python script tool and a loop that steps ...