Imagine your organization has been tasked to evaluate potential sites for a new warehouse. This evaluation is to be based on access to transportation, the presence of special restrictions such as nearby historical neighborhoods, access to restaurants and other facilities that employees may need, access to public transportation for employees, and nearby land use that may restrict or enhance development. How does your organization evaluate these sites in a quantifiable and defensible way? Of course, your organization needs data, but it also needs tools to analyze the data, measure geographic relationships, and help answer the question. This process is known as spatial analysis.
Many patterns and relationships aren't always obvious from looking at a map. In some cases, there may be too much data to present coherently. The way you display the data on the map can change the patterns you see. Spatial analysis tools allow you to quantify patterns and relationships in the data and display the results as maps, tables, and charts. As of 10.4, these tools are available in Portal for ArcGIS. They allow you to provide portal members with a fast, accessible way to perform many common spatial analysis workflows.
The tools you'll use to perform spatial analysis are actually hosted as a series of tasks in ArcGIS Server. To expose the tools to members of your portal, complete the steps in the Configure the portal to perform analysis section.
Members of your organization will have no direct interaction with ArcGIS Server; they will only use the Portal for ArcGIS website to perform analysis. For example, members will use the analysis tools to perform common analytical functions such as finding hotspots, locating streets and addresses, finding a place, routing, or accessing a geodatabase. By enabling analysis, you empower members of your organization to answer questions and make important decisions using more than visual analysis.
To learn more about each tool, see the About the analysis tools section. To learn more about accessing and running the tools, see the Perform analysis section in the Portal for ArcGIS Help.
Configure the portal to perform analysis
The spatial analysis tools are hosted as a series of tasks in ArcGIS Server. For members of your organization to use these tasks to perform analysis in Portal for ArcGIS, you'll need to set up a hosting server for your portal using ArcGIS Data Store and grant members privileges to perform analysis. The hosting server does the work of processing analysis requests, storing the results in ArcGIS Data Store, and returning results to members in the Portal for ArcGIS website. You cannot use a hosting server configured with an enterprise geodatabase for this purpose.
The following instructions may require changes to the way you've deployed ArcGIS in your organization; review them carefully before proceeding. To configure the portal to perform analysis, follow these steps:
Note:
You can configure analysis for a portal that has been upgraded from an earlier version. Your portal must have a hosting server configured with ArcGIS Data Store. Follow the steps in Upgrade Portal for ArcGIS, and then go to My Organization > Edit Settings > Servers. Click Enable and save your settings. You can then proceed to step 5 below.
- Install ArcGIS Server and ArcGIS Data Store.
- Create an ArcGIS Data Store and register it with your ArcGIS Server site.
- Federate your ArcGIS Server site with your portal.
- Specify the ArcGIS Server site as your portal's hosting server.
- Grant members privileges to perform analysis. Publisher and spatial analysis privileges are needed to perform analysis.
- Optionally, configure additional utility services with your portal. See the analysis tool descriptions below for more information about which tools require which additional utility services. Note that tools that require network utility services require that all of the network utility services be registered with the portal. For more information about the utility services, see About utility services.
About the analysis tools
The analysis tools are arranged in categories. These categories are logical groupings and do not affect how members of your organization access or use the tools in any way.
Note:
If the necessary utility services for a tool are not configured, the tool will not be visible in the portal user interface. The tool will also not be visible if a portal member does not have the correct permissions to use that tool.
The categories are as follows:
Summarize data
These tools calculate total counts, lengths, areas, and basic descriptive statistics of features and their attributes within areas or near other features.
| Tool | Description |
|---|---|
| Aggregate Points | This tool works with a layer of point features and a layer of area features. It first figures out which points fall within each area. After determining this point-in-area spatial relationship, statistics about all points in the area are calculated and assigned to the area. The most basic statistic is the count of the number of points within the area, but you can get other statistics as well. For example, suppose you have point features of coffee shop locations and area features of counties, and you want to summarize coffee sales by county. Assuming the coffee shops have a TOTAL_SALES attribute, you can get the sum of all TOTAL_SALES within each county, or the minimum or maximum TOTAL_SALES within each county, or the standard deviation of all sales within each county. |
| Summarize Nearby | This tool finds features within a specified distance of features in the analysis layer. Distance can be measured as a straight-line distance or a selected travel mode. Statistics are then calculated for the nearby features. For example:
Note:Travel mode distance calculations require that you configure the portal to use network utility services and grant the Network Analysis privilege to those members who need to run the tool. |
| Summarize Within | This tool finds features (and portions of features) within the boundaries of areas in the analysis layer. For example:
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Find locations
These tools find features that pass any number of criteria that you specify. They are typically used for site selection, where the objective is to find places that satisfy multiple criteria.
| Tool | Description |
|---|---|
| Find Existing Locations | This tool selects existing features in your study area that meet a series of criteria you specify. These criteria can be based on attribute queries (for example, parcels that are vacant) and spatial queries (for example, parcels within 1 mile of a river). |
| Derive New Locations | This tool derives new features in your study area that meet a series of criteria you specify. These criteria can be based on attribute queries (for example, parcels that are vacant) and spatial queries (for example, parcels that are within flood zones). |
| Find Similar Locations | Based on criteria you specify, the Find Similar Locations tool measures the similarity of locations in your candidate search layer to one or more reference locations. |
| Create Viewshed | This tool creates areas were an observer can see objects on the ground. The input analysis points can represent either observers (such as people on the ground or lookouts in a fire tower) or observed objects (such as wind turbines, water towers, vehicles, or other people). The result areas are those areas where the observers can see the observed objects and vice versa: the observed objects can see the observers. The output is typically used in site suitability and selection analysis. Note:This tool requires you to configure the elevation utility service for the portal, and grant the Elevation Analysis privilege to any members who need to run the tool. |
| Create Watersheds | This tool identifies catchment areas based on locations that you specify. Note:This tool requires you to configure the hydrology utility service for the portal, and grant the Elevation Analysis privilege to any members who need to run the tool. |
| Trace Downstream | This tool determines the trace, or flow path, in a downstream direction from the points in your analysis layer. Note:This tool requires you to configure the hydrology utility service for the portal, and grant the Elevation Analysis privilege to any members who need to run the tool. |
Data enrichment
These tools help you explore the character of areas. Detailed demographic data and statistics are returned for your chosen areas. Comparative information can also be reported for expanded areas such as counties and states.
| Tool | Description |
|---|---|
| Enrich Layer | This tool enriches your point or area data by getting facts about the people, places, and businesses that surround your data locations. Enrich Layer enables you to answer new questions about locations that you cannot answer with maps alone; for example, What kind of people live here? What do people like to do in this area? What are their habits and lifestyles? What kind of businesses are there in this area? The result will be a new layer containing all demographic and geographic information from given data collections. This new information is added as fields in the table. Note:This tool requires a GeoEnrichment utility service, and any members who need to run the tool require the GeoEnrichment privilege. Additionally, travel mode distance calculations require that you configure the portal to use network utility services and grant the Network Analysis privilege to those members who need to run the tool. |
Analyze patterns
These tools help you identify, quantify, and visualize spatial patterns in your data by identifying areas of statistically significant clusters.
| Tool | Description |
|---|---|
| Calculate Density |  The Calculate Density tool creates a density map from point or line features by spreading known quantities of some phenomenon (represented as attributes of the points or lines) across the map. The result is a layer of areas classified from least dense to most dense. For example
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| Find Hot Spots |  The Find Hot Spots tool will determine if there is any statistically significant clustering in the spatial pattern of your data.
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| Interpolate Points |  The Interpolate Points tool allows you to predict values at new locations based on measurements from a collection of points. The tool takes point data with values at each point and returns areas classified by predicted values. For example
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Use proximity
These tools help you answer one of the most common questions posed in spatial analysis: "What is near what?"
| Tool | Description |
|---|---|
| Create Buffers |  A buffer is an area that covers a given distance from a point, line, or area feature. Buffers are typically used to create areas that can be further analyzed using a tool such as Overlay Layers. For example, if the question is "What buildings are within one mile of the school?", the answer can be found by creating a one-mile buffer around the school and overlaying the buffer with the layer containing building footprints. The end result is a layer of those buildings within one mile of the school. |
| Create Drive-Time Areas |  Create Drive-Time Areas creates areas that can be reached within a specified drive time or drive distance. It measures out from one or many points (up to 1,000), along roads, to create a layer that can help you answer questions such as:
You may be able to answer your questions solely through visualizing the output areas. Alternatively, you can perform further spatial analysis using the output areas. For instance, running Aggregate Points using drive-time areas with demographic data can help determine which potential store location would likely provide the best customer base for your type of business. Note:You must configure network utility services on the portal and grant members the Network Analysis privilege to allow them to run this tool. |
| Find Nearest |  This tool finds the nearest features and, optionally, reports and ranks the distance to the nearby features. To find what's nearby, the tool can either measure straight-line distance or a selected travel mode. There are options to limit the number of nearest features to find or the search range in which to find them. The results from this tool can help you answer the following kinds of questions:
Find Nearest returns a layer containing the nearest features and, optionally, a line layer that links the start locations to their nearest locations. The optional line layer contains information about the start and nearest locations and the distances between. Note:To allow members to find nearby features using one of the available travel modes, you must configure network utility services for the portal and grant members the Network Analysis privilege. |
| Plan Routes |  Plan Routes determines how to efficiently divide tasks among a mobile workforce. You provide the tool with a set of stops and the number of vehicles available to visit the stops. The tool assigns the stops to vehicles and returns routes showing how each vehicle can reach their assigned stops in the least amount of time. With Plan Routes, mobile workforces reach more jobsites in less time, which increases productivity and improves customer service.
The output from Plan Routes includes a layer of stops coded by the routes to which they are assigned, a layer of routes showing the shortest paths to visit assigned stops, and, depending on whether any stops could not be reached, a layer of unassigned stops. Note:You must configure network utility services on the portal and grant members the Network Analysis privilege to allow them to run this tool. |
| Connect Origins to Destinations | This tool measures the travel time or distance between pairs of points. The tool can report straight-line distances, road distances, or travel times. You provide starting and ending points, and the tool returns a layer containing route lines, including measurements, between the paired origins and destinations. If many origins go to one destination, a table summarizing multiple trips to the destination is included in the output. Note:You must configure network utility services on the portal and grant members the Network Analysis privilege to allow them to run this tool. |
Manage data
These tools are used for both the day-to-day management of geographic data and for combining data prior to analysis.
| Tool | Description |
|---|---|
| Extract Data |  With this tool, you can select and download data for a specified area of interest. Layers that you select will be added to a zip file or layer package. |
| Dissolve Boundaries |  Areas that overlap or share a common boundary are merged together to form a single area. You can control which boundaries are merged by specifying a field. For example, if you have a layer of counties, and each county has a State_Name attribute, you can dissolve boundaries using the State_Name attribute. Adjacent counties will be merged together if they have the same value for State_Name. The end result is a layer of state boundaries. |
| Merge Layers |  This tool copies features from two layers into a new layer. The layers to be merged must all contain the same feature types (points, lines, or areas). You can control how the fields from the input layers are joined and copied. For example:
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| Overlay Layers |  Overlay Layers combines two or more layers into one single layer. You can think of overlay as peering through a stack of maps and creating a single map containing all the information found in the stack. In fact, before the advent of GIS, cartographers would literally copy maps onto clear acetate sheets, overlay these sheets on a light table, and hand draw a new map from the overlaid data. Overlay is much more than a merging of line work; all the attributes of the features taking part in the overlay are carried through to the final product. Overlay is used to answer one of the most basic questions of geography, "What is on top of what?" For example:
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