The process of extracting geographic, statistical, geometric, or scientific information from one or more related collections of GIS features and data.

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26 views

How to do Network Kernel Density Estimation Analysis in ArcGIS?

I am looking at doing some analysis of road traffic collisions. Obviously collisions occur on stretch of roads and I was reseraching the best methodology to take into account the network element of ...
5
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2answers
94 views

Calculating edge length of polygon within overlapping polygon

I have a layer of wetland polygons and a layer of lakes. I basically want to find the total length of lake shoreline contained within each wetland and add these values as an attribute of the wetlands. ...
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1answer
39 views

error in selecting data from attrribute table QGIS

First of all, im not sure why all the data points from my csv file does not show up on qgis. I enabled custom delimiters to commas and still have no clue. it worked for my other vector layers except ...
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1answer
39 views

non alignment of base layer and other vector layers

i'm sure you've encountered this problem repeatedly. i've tried all different methods. Enable on the fly crs transformation. go to settings and options to use crs data. go to properties and change ...
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1answer
48 views

Analyzing long lat location data to find locations in proximity

I am looking for a tool to analyze location data (long lat values from vehicle GPS available). The goal is to identify locations which are in close proximity (within a circle of 30-60ft) and then ...
4
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1answer
78 views

Measuring Sinuosity of Walking Paths

I'm currently working on a project that examines the movement of consumers through different kinds of retail spaces in Central Asia – namely, bazaars versus supermarkets. I've equipped dozens of ...
3
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1answer
77 views

Calculate and add area of overlapping features within polygons

I have a polygon layer of watershed boundaries And a single multipart feature that contains all public lands for the state. I need to find the area of public lands within each watershed and add it ...
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1answer
27 views

How to add analysis privileges to ArcGIS Online application?

I'd like to use ArcGIS Online analysis services in my web app application. When I try accessing the service: http://analysis.arcgis.com/arcgis/rest/services/tasks/GPServer?f=pjson&token= I get ...
14
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3answers
612 views

Using GIS tools for non-geographical problems

Many other fields have visual/"spatial" problems that can potentially be solved with GIS tools. I know I've used GIS tools for the odd non-geographical task and was wondering how much this happens and ...
4
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1answer
108 views

Identifying south facing mountain land, above an elevation, within a slope range, less than fixed distance from major roadways

This odd question comes from believing that such an analysis is plausible in a GIS system. Only, I don't how to accomplish the various discrete steps implied from the Title, nor where to get a topo ...
2
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1answer
30 views

How to compute areas where the value in one layer is smaller than in another layer?

I have two vector layers, one contains actual values (in this case % cover of native species), the other contains target vales of the same attribute. the polygons are not always of the same geometry. ...
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0answers
24 views

findind depression in cloud point and dtm

I would like to find temporary moist areas based on terrain surface shape (depression) directly from cloud point data (ALS) and DTM. Could you help me to find some tools or algorithm to solve the ...
3
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1answer
70 views

How to perform tree birthrate and mortality research with GIS [closed]

I'm using QGIS 2.6 and have 4 layers of polygons. Each of these polygons describes the outline of a tree, based on airborne imagery. My goal is to find the relations between every synchronously ...
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1answer
65 views

Using same line to interpolate multiple rasters, and put all profiles on same graph, using ArcGIS for Desktop?

I'm new to the website and new to ArcMap so please bear with me. I'm struggling with the "interpolate line" function on ArcMap. Long story short (hopefully): I have some bathymetry rasters of an ...
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2answers
95 views

How can I calculate how many of a certain feature lie within my various buffer rings?

I am using ArcMap and I have a series of real estate parcels mapped along with a series of wind turbines. I have created multiple buffer rings around each real estate parcel with distances (0.5, 1, ...
3
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2answers
77 views

QGIS calculates main soil type of polygons from another polygon layer

I've been working with qgis for a while but somehow I never fiured this out, so I thought it's time to ask. I have 2 shapefiles. a polygon layer from nearby fields (SHAPE1 (the red outlines)) a ...
1
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0answers
38 views

how to use line feature as stops input in network analyst?

I'm trying to build a certain route with network analyst on a Network Dataset. As an input to create the route I want to use line features. I am trying to do this with network analyst in ArcGIS 10.0 ...
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0answers
45 views

Get pixel values ascii 50 files

I´m working with photos from a cam. The cam is arranged to take ndvi values instead of RGB for each pixel. I have several folders with 50 pictures in each folder as '*.asc' files the pictures. I am ...
2
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1answer
38 views

Clip_Management seems to delete shapefile?

We have some python code that clips a very large shapefile for further processing. We can see the process create all the output files, but then just as the process is finishing, they get deleted. ...
2
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1answer
66 views

Performing equivalent of ArcGIS Identity_analysis (line with poly) using PostGIS?

I've got a section of arcpy code that I need to port PostGIS: Identity_analysis with the in_features being a line featureclass and the identity_features being a polygon featureclass. I'm primarily ...
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0answers
38 views

How to produce a simple ZTV/ZVI in openWind?

I'm struggling to get to grips with openWind. I need to produce a ZTV showing a 5km radius around the chimney of a proposed industrial development. I'm not sure of the height of the stack yet but for ...
9
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5answers
448 views

GIS analysis to find duplicate geometries

I have a big shapefile that contains all the buildings and houses of the town that I work in (approx. 90,000 features). The data of the buildings/houses are saved by the town's surveying engineers and ...
0
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1answer
47 views

Looping Summary Statistics on changing field name

I am trying to calculate summary statistics for a number of shapefiles, which is easy enough, but the field name for each shapefile is different. The field name is identical to the file name if that ...
4
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1answer
69 views

Is it possible, and if so how, to effectively classify vegetation types using false near infra red imagery?

Background : I use near infra-red imagery to delineate wetlands and water bodies with good success. It's also obvious to distinguish between new healthy vegetation and older growth and land areas with ...
2
votes
1answer
133 views

How to batch process near feature distance in ArcGIS

I have 2000+ point shape files. These are all GPS tracks. I want to calculate the distance from each point to the nearest feature (road, train line, restaurant etc) within a 30 meter radius. I am ...
5
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2answers
1k views

Are GIS Analyst salaries going to always be so low? [closed]

I regularly see GIS Analyst job postings (often in very expensive cities) asking for a plethora of experience paying in the $40k - 60k a year range, many are even below $40k or $30k. Considering the ...
3
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1answer
73 views

Statistical Analysis of Shapefile Proximity within Raster Image - ArcMap10.1

I have a raster image that has been reclassified into 15 equally incremented values/levels. This raster represents "sinkhole risk" in a certain county. So level 1 is the lowest risk region and level ...
0
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2answers
69 views

Frequency analysis and overlay analysis

Am new to gis and I hope to find help here. I am working on a research that requires that I overlay conditions of drainage systems and quality of healthcare in a coastal state to get areas which have ...
4
votes
2answers
138 views

Identify cluster centroids

I have a data set of points which are grouped into clusters like so: I'd like to use ArcGIS or Python to create a point layer of the centroids of each cluster but I can't seem to find the right ...
0
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1answer
148 views

How to colour contour lines in .shp file when the lines are not meeting in QGIS?

I am doing bathymetry analysis, where I would like to color the contours one by one in the case land is rising (or sea level going down). There is a comprehensive explanation about coloring contours ...
2
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0answers
103 views

FME - Raster Algebra and Multicriteria Analysis

I'm trying to use FME to do some raster algebra for some Multi-Criteria Analysis. At the moment, I have three rasters, all with the same extents and resolution: Slope, Hydro, and Infrastructure Mask. ...
1
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1answer
96 views

How to dissolve adjacent parcels by same owner but include those parcels located across the street with the same owner?

In trying to determine the total contiguous stream length per landowner, I dissolved parcels by parcel owner name attribute and intersected these dissolved parcels with streams. However, dissolving ...
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0answers
79 views

network based interpolation methods, which one could I use?

I need to interpolate traffic data consisting in raw number of vehicles passing across certain points, where counters are. It is evident I haven't a uniform distribution of points and values about ...
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0answers
144 views

Finding shortest cumulative route (i.e. best 'hub') between networked points

How do I find the shortest cumulative route (i.e. best 'hub') between networked points? I have a dataset where some but not all of the points in the network connect to each other, however it is ...
3
votes
0answers
91 views

How to create cost surface for least cost water transport analysis?

I am working on a project to derive least cost pathways between sites by dug out canoe travel. Has anyone worked on a similar project or found a function like the Tobler hiking function that can be ...
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0answers
34 views

Analyse effect of groups on raster maps

I work with a mechanistic model that uses climate data to simulate some specific output for different time steps and spatial locations. Now I want to investigate the effect of different climate data ...
9
votes
1answer
293 views

When dealing with rasters of varying resolutions should one resample to the highest or lowest resolution?

I'm looking for recommendations on best practices for dealing with raster data layers with different resolutions and projections. The advice I've been given is to always resample to the layer with the ...
3
votes
2answers
46 views

What type of remote sensing methodology is commonly used to locate and track the movement of woodland caribou herds?

I am most curious whether it is possible to use Landsat or other freely available imagery (but info on any other method would great as well) to locate and track the movement of woodland caribou herds ...
1
vote
1answer
109 views

Calculating distance between borders when one polygon inside another polygon?

I am brand new to ArcGIS and having some trouble. I would like to calculate the distances between the border of one polygon to another polygon. However, these polygons overlap. Thus when I use the ...
1
vote
1answer
179 views

ArcGIS “Zoom to layer” scale

I'd like to quickly inspect the features in a feature class by double clicking the row in the table view and looking at the surrounding base layer. This works, but the feature fills the screen, so I ...
1
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1answer
81 views

How does the tolerance influence QgsGraphBuilder and tieing of points?

I am developing a script which uses OpenStreetMap data to calculate the distance (over the road network) between each building and the nearest hospital. To do this, I mainly follow the official ...
1
vote
2answers
445 views

Creating flat end type polylineline buffer in model without ArcGIS advanced

I have a polyline split into many short segments and would like to create a flat end buffer for each individual segment (not "dissolve" them all into one feature). Is there any way to do this in an ...
3
votes
2answers
462 views

Creating square buffer in qgis

How can I create a buffer with square ends along a line segment in qgis? I've buffered lines using v.buffer in the GRASS plugin, but the -c option for square ends is not exposed in that interface. ...
2
votes
0answers
74 views

Finding obstructions along a stream with LIDAR

I'm trying to find obstructions to boat traffic (downed trees, collapsed bridges, etc) along medium sized streams (5-15m across). The obstructions may or may not obstruct water flow. I have good ...
2
votes
1answer
206 views

GIS Analysis - best way to combine and display demographic data?

I am currently undertaking a demographic research project for my employer. We have the data on income, age, sex, language, transport etc and I have mapped most of it and created some thematics of said ...
3
votes
1answer
115 views

Add more info in the attribute table after executing “Line intersection” in QGIS

I have executed the "Line intersection" tool on a road shapefile. This is under Vector > Analysis Tools > Line intersections. I get an output with attribute table having just two columns: type_1 ...
18
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4answers
2k views

What are the benefits of hexagonal sampling polygons?

I am always on the lookout for useful methods to sample or partition study areas (usually in the form of raster datasets) into smaller units. Recently, I read an ESRI blog post about a new tool for ...
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2answers
135 views

How to get layer extension info via Arcpy

I want to get file format of a layer with using Arcpy. I am writing a tool that needs to take raster or feature extension like SHP, TIFF etc. Which functions should i use ? Note: I use ArcGIS 10
4
votes
1answer
396 views

What is the FME Equivalent to the ArcGIS Union tool?

I'm attempting to union 2 large featureclasses in ArcCatalog, QGIS, and FME. What is the transformer that would be equivalent to the ArcGIS Union tool?
2
votes
1answer
370 views

GTOPO30 Slope analysis in ArcGIS 10.1 [duplicate]

Using surface - slope analysis tool box. All values for the slope calculation are in between 80 and 89. There are no values below 80. What am I doing wrong?