Introduction to GIS modeling and Python

Overview

Welcome to http://assistance-en-sig.blogspot.com/. Over the next ten weeks you'll work through four lessons and a final project dealing with ArcGIS automation in Python. Each lesson will contain readings, examples, and projects. Since the lessons are two weeks long, you should plan between 20 - 24 hours of work to complete them, although this number may vary depending on your prior programming experience. See the Course Schedule section of this syllabus, below, for a schedule of the lessons and course projects.

As with GEOG 483 and GEOG 484, the lessons in this course are project-based with key concepts embedded within. However, because of the nature of computer programming, there is no way this course can follow the step-by-step instruction design of the previous courses. You will probably find the course to be more challenging than the others. For that reason, it is more important than ever that you stay on schedule and take advantage of the course message boards and private e-mail. It's quite likely that you will get stuck somewhere during the course, so before getting hopelessly frustrated, please seek help from me or your classmates!

I hope that by now that you have reviewed our Orientation and Syllabus for an important course site overview. Before we begin our first project, let me share some important information about the textbook and a related Esri course.

Textbook and readings

The textbook for this course is Python Scripting for ArcGIS by Paul A. Zandbergen. This book came out in 2012 and has been a hot item among Esri software users; I suggest you order your copy immediately in case of shortages or delays.

Back when Geog 485 was rewritten as a Python course, there was no textbook available that tied together ArcGIS and Python scripting. As you read through Zandbergen's book, you'll see material that closely parallels what is in the Geog 485 lessons. This isn't necessarily a bad thing; when you are learning a subject like programming, it can be helpful to have the same concept explained from two angles.

My advice about the readings is this: Read the material on the Geog 485 lesson pages first. If you feel like you have a good understanding from the lesson pages, you can skim through some of the more lengthy Zandbergen readings. If you struggled with understanding the lesson pages, you should pay close attention to the Zandbergen readings and try some of the related code snippets and exercises. I suggest you plan about 1 - 2 hours per week of reading if you are going to study the chapters in detail.

In all cases, you should get a copy of the textbook because it is a relevant and helpful reference.

Esri Virtual Campus Courses Using Python in ArcGIS Desktop 10

There is a free Esri Virtual Campus course, Using Python in ArcGIS Desktop 10, that introduces a lot of the same things you'll learn this quarter in Geog 485. The course consists of a one-hour recorded seminar and a walkthrough exercise. If you want to get a head start, or you feel you want some reinforcement of what we're learning from a different point of view, it would be worth your time to complete this Virtual Campus course.

All you need in order to access this course is an Esri Global Account, which you can create for free. You do not need to obtain an access code from Penn State.

The video moves very quickly and covers a range of concepts that we'll spend 10 weeks studying in depth, so don't worry if you don't understand it all immediately. You might find it helpful to watch the video again near the end of Geog 485 to review what you've learned.

Questions?

If you have any questions now or at any point during this week, please feel free to post them to the Lesson 1 Discussion Forum. (To access the forums, return to ANGEL via the ANGEL link in the Resources menu. Once in ANGEL, you can navigate to the Communicate tab and then scroll down to the Discussion Forums section.) While you are there, feel free to post your own responses if you, too, are able to help a classmate.

Now, let's begin Lesson 1.

• Lesson 1 checklist
• 1.1.1 The need for GIS automation
• 1.2.1 Exploring the toolbox
• 1.2.2 Environments for accessing tools
• 1.2.3 Running a tool from its GUI
• 1.2.4 Modeling with tools
• 1.3.1 Why learn ModelBuilder?
• 1.3.2 Opening and exploring ModelBuilder
• 1.3.3 Model parameters
• 1.3.4 Advanced geoprocessing and ModelBuilder concepts
• 1.4.1 Introducing Python using the Python window in ArcGIS
• 1.4.2 What is Python?
• 1.4.3 Installing Python and PythonWin
• 1.4.4 Exploring PythonWin
• 1.5.1 Working with variables
• 1.5.2 Objects and object-oriented programming
• 1.5.3 Classes
• 1.5.4 Inheritance
• 1.5.5 Python syntax
• 1.6.1 Introductory Python examples
• 1.6.2 Example: Printing the spatial reference of a feature class
• 1.6.3 Example: Performing map algebra on a raster
• 1.6.4 Example: Creating buffers
• 1.7.1 Making a script tool
• Lesson 1 Practice Exercises
• Project 1, Part I: Modeling precipitation zones in Nebraska
• Project 1, Part II: Creating contours for the Fox Lake DEM

1.2.1 Exploring the toolbox

The ArcGIS software that you use in this course contains hundreds of tools that you can use to manipulate and analyze GIS data. Back before ArcGIS had a graphical user interface (GUI), people would access these tools by typing commands. Nowadays, you can point and click your way through a whole hierarchy of toolboxes using ArcCatalog or the Catalog window in ArcMap.

Although you may have seen them before, let’s take a quick look at the toolboxes:

1. Open ArcMap.
2. If the Catalog window isn't visible, click the Windows menu, then click Catalog. (If you've used previous versions of ArcGIS, this is a new window at version 10 that allows you to have a lot of the ArcCatalog functionality available in ArcMap.) If you hover over or click the Catalog item on the right side of your screen, you can make the Catalog window appear. Optionally, you can "pin" it down so that it doesn't hide itself.
3. In the Catalog, expand the nodes Toolboxes > System Toolboxes and continue expanding the toolboxes of your choice until you see some of the available tools. Notice that they’re organized into toolboxes and toolsets. Sometimes it’s faster to use the Search window to find the tool you need instead of browsing this tree.
4. Let’s examine a tool. Expand Analysis Tools > Proximity > Buffer, and double-click the Buffer tool to open it.
   At this point, you’re looking at a dialog with many fields. Each geoprocessing tool has required inputs and outputs. Those are indicated by the green dots. They represent the minimum amount of information you need to supply in order to run a tool. For the Buffer tool, as inputs, you’re required to supply an input features location (the features that will be buffered) and a buffer distance. You’re also required to indicate an output feature class location (for the new buffered features).
   Many tools also have optional parameters. You can modify these if you want, but if you don’t supply them, the tool will still run using default values. For the Buffer tool, optional parameters are the Side Type, End Type, Dissolve Type, and Dissolve Fields. Optional parameters are typically specified after required parameters.
5. Click the Show Help button in the lower-right corner of the tool (if it says Hide Help then you’re already viewing help). You can now click on any parameter in the dialog to see an explanation of that parameter appear in the right-hand window.
   If you’re not sure what a parameter means, this is a good way to learn. For example, with the help still open, click the Side Type input box on the Buffer tool (right where it says "FULL"). The Help explains what the Side Type parameter means and lists the different options: FULL, LEFT, RIGHT, and OUTSIDE_ONLY.

If you need even more help, each tool is fully documented in the ArcGIS Desktop Help. You could go directly to the Buffer tool help by clicking the Tool Help button in the tool dialog box, but in this course you'll often want to get to these help pages without opening the tool itself. Below are the steps for doing so.

1. From the main menu of ArcMap, click Help > ArcGIS Desktop Help. Optionally, for the most up-to-date help, you can use the Web-based help at http://webhelp.esri.com. (All links to the Help in this course will open the Web Help.)
2. In the ArcGIS Desktop Help table of contents, expand Professional Library > Geoprocessing > Geoprocessing tool reference. (If you are using 10.1, browse to Geoprocessing > Tool Reference instead.) Notice that the help topics in this section are organized into toolboxes and toolsets, paralleling the layout of the ArcGIS System Toolboxes.
3. Continue navigating the help table of contents to Analysis toolbox > Proximity toolset > Buffer. Scroll through the entire topic examining all the information that is given about the Buffer tool. Here you get tips about what the Buffer tool does, how to use it, a full list of parameters, and scripting examples written in Python. These scripting examples will be extremely valuable to you as you complete the assignments in this course and you should always check the Geoprocessing Tool Reference in the Help if you’re having trouble getting a tool to run in Python.

1.1.1 The need for GIS automation

A geographic information system (GIS) can manipulate and analyze spatial datasets with the purpose of solving geographic problems. GIS analysts perform all kinds of operations on data to make it useful for solving a focused problem. This includes clipping, reprojecting, buffering, merging, mosaicking, extracting subsets of the data, and hundreds of other operations. In the ArcGIS software used in this course, these operations are known asgeoprocessing and they are performed using tools.

Successful GIS analysis requires selecting the right tools to operate on your data. ArcGIS uses a toolbox metaphor to organize its suite of tools. You pick the tools you need and run them in the proper order to make your finished product.

Suppose you’re responsible for selecting sites for video stores. You might use one tool to select land parcels along a major thoroughfare, another tool to select parcels no smaller than 0.25 acres, and other tools for other selection criteria.  If this selection process were limited to a small area, it would probably make sense to perform the work manually. 

However, let’s suppose you’re responsible for carrying out the same analysis for several areas around the country.  Because this scenario involves running the same sequence of tools for several areas, it is one that lends itself well to automation. There are several major benefits to automating tasks like this:

• Automation makes work easier. Once you automate a process, you don't have to put in as much effort remembering which tools to use or the proper sequence in which they should be run.
• Automation makes work faster. A computer can open and execute tools in sequence much faster than you can accomplish the same task by pointing and clicking.
• Automation makes work more accurate. Any time you perform a manual task on a computer, there is a chance for error. The chance multiplies with the number and complexity of the steps in your analysis. In contrast, once an automated task is configured, a computer can be trusted to perform the same sequence of steps every time.

ArcGIS provides three ways for users to automate their geoprocessing tasks. These three options differ in the amount of skill required to produce the automated solution and in the range of scenarios that each can address.

The first option is to construct a model using Model Builder. Model Builder is an interactive program that allows the user to “chain” tools together, using the output of one tool as input in another. Perhaps the most attractive feature of Model Builder is that users can automate rather complex GIS workflows without the need for programming. You will learn how to use Model Builder early in this course.

Some automation tasks require greater flexibility than is offered by Model Builder, and for these scenarios it's recommended that you write scripts. The bulk of this course is concerned with script writing.

A script is a program that executes a sequential procedure of steps. Within a script, you can run GIS tools individually or chain them together. You can insert conditional logic in your script to handle cases where different tools should be run depending on the output of the previous operation. You can also include iteration, or loops, in a script to repeat a single action as many times as needed to accomplish a task.

There are special scripting languages for writing scripts, including Python, JScript, and Perl. Often these languages have more basic syntax and are easier to learn than other languages such as C, Java, or Visual Basic.

Although ArcGIS supports various scripting languages for working with its tools, Esri emphasizes Python in its documentation and includes Python with the ArcGIS install. In this course we’ll be working strictly with Python. You’ll learn the basics of the Python language, how to write a script, and how to manipulate and analyze GIS data using scripts. Finally, you’ll apply your new Python knowledge to a final project, where you write a script of your choosing that you may be able to apply directly to your work.

The third option available to ArcGIS users looking to automate geoprocessing is to build a solution using ArcObjects, the programming building blocks used by Esri’s own developers to produce the ArcGIS desktop products. With ArcObjects, it is possible to customize the user interface to include specific commands and tools that either go outside the abilities of the out-of-the-box ArcGIS tools or modify them to work in a more focused way. ArcObjects programming and interface customization are outside the scope of this course, but are covered in the GIS Application Development course, GEOG 489. GIS customization with ArcObjects can be an advanced endeavor, and learning a scripting language like Python is a good way to prepare yourself by learning basic programming concepts.

The tools that you run in ModelBuilder and Python actually use ArcObjects "under the hood" to run GIS functions; however, the advantage of Python scripting with ArcGIS is that you don't need to learn all the ArcObjects logic behind the tools. Your job is just to learn the tools and how to run them in the appropriate order to accomplish your task.

This first lesson will introduce you to concepts in both model building and script writing. We’ll start by just getting familiar with how tools run in ArcGIS and how you can use those tools in the ModelBuilder interface. Then, we’ll cover some of the basics of Python and see how the tools can be run within scripts.

Lesson 1 checklist -ArcGIS Python

This lesson is two weeks in length. (See the Calendar in ANGEL for specific due dates.) To finish this lesson, you must complete the actvities listed below. You may find it useful to print this page so that you can follow along with the directions. 

1. Download the Lesson 1 data and extract it to C:\WCGIS\Geog485\Lesson1 or a similar path that is easy to remember.
2. Work through the online sections of Lesson 1.
3. Read Zandbergen chapters 2 - 3. In the online lesson pages I have inserted instructions about when it is most appropriate to read each of these chapters.
4. Complete Project 1, Part I and submit the deliverables to the course drop box.
5. Complete Project 1, Part II and submit the deliverables to the course drop box.
6. Complete the Lesson 1 Quiz.

MyGeodata Converter - format converting, coordinate system transformation, data processing

General information: MyGeodata Converter allows you to read and write from/to a huge number of CAD and GIS formats - both vector and raster. MyGeodata Converter is more than only simply data converter! In contrast to common format convertion MyGeodata Converter allows sofisticated data processing during conversion. MyGeodata Converter also can be used as a powerful tool for collective data and attributes processing.

Solution: Use on-line MyGeodata Converter available HERE. Just pack all filles belonging to one or more datasets to a single ZIP file and follow instructions...

Remote Sensing and GIS techniques applied to geological survey

Summary

This application shows how a GIS in combination with geological data sets can be used to solve specific geological problems. The training on digital image processing focuses on the usage of field and laboratory spectral data to gain a better understanding of Remote Sensing products. Advanced image processing techniques are introduced and applied using Landsat Thematic Mapper data of the Ronda-Malaga area. The Ronda-Malaga area is located in the southern part of Spain, West of the city of Malaga and Southeast of the city of Ceville.

Mineral exploration

Geologically the Ronda-Malaga area is part of the Betic Cordillera foldbelt stretching from Alicante to Cadiz in southern Spain. By combining the information that is available in digital geological maps and in attribute tables it is possible to create new maps. In this exercise two maps are created to guide in mineral exploration:

• A map showing the possible locations of copper mineralizations, and
• A map showing the potential gold deposits.

It is known that copper mineralizations occur along faults within limestones of Jurassic age and that the Permian sandstones in areas adjacent to Ronda could host gold mineralizations when they occur along normal faults. You can get further information, such as the total area or the average size of the outcrops by using Aggregation functions on the histograms of these two maps. Finally, you can analyze the density of lineaments with respect to the lithology creating a lineament density map with the Segment Density operation.

Working with the Digital Terrain Model

In geology a Digital Terrain Model (DTM) is often used to investigate the geomorphologic characteristics of the terrain in relation to the underlying influence of geology. The DTM for the Ronda-Malaga area is created by first producing a sub map of the contour segment map and subsequently interpolating the digitized contour lines of the sub map. Based on the DTM a slope map can be calculated by applying the gradient filters DFDX and DFDY and a MapCalc formula to the DTM. The slope map can for example be compared with the geology and the fracture pattern.
A pseudo relief image can be created using artificial illumination of the DTM. This technique is known as hillshading. In ILWIS hillshading is done by using the standard Shadow filter creating a pseudo relief map with artificial illumination from the Northwest or by creating a user-defined filter that simulates a different illumination.
In ILWIS it is also possible to create real three dimensional perspective views of the terrain. In this case the DTM is used as height map over which other maps (e.g. geology, lithology) can be draped.

 

Image enhancement

In order to improve the visual appearance of the TM data various standard image processing tricks can be performed. Applying the stretch function, and some smoothing, sharpening and gradient filters on the TM bands enhances the contrast of the images.
Selecting three bands for display in a color composite image is a tedious and time consuming business since many combinations have to be tried certainly when working with ratio images.
The Optimum Index Factor technique (OIF) may help to overcome this problem. High OIF values indicate bands that contain much "information" (e.g. high standard deviation) with little "duplication" (e.g. low correlation between the bands). By using the OIF method, three band color composites can be evaluated on their effectiveness for display.

 Color composite TM456

Spectral recognition of surface reflectors

The pixel information window can be used to investigate the DN values of the TM bands simultaneously in order to find the spectral responses of unknown ground cover types. For these unknown ground cover types you are asked to say what they are likely to be comparing their reflectance characteristics to the materials in the table containing laboratory spectral data.

Rationing

A common problem with RS images is the effect of varying illumination caused by topography. Relief causes some slopes to be illuminated more than others, thus surfaces with homogeneous reflectance properties will show varying DN values across a scene. Ratio images provide a means of correcting these differences. Creating ratio images is done using the following general formula in MapCalc:

Ratio(Tm_i/TM_j) = (Tmi/TMj) * 127

The importance of ratio images is that they map a spectral gradient and can therefore be used to map e.g. iron content, clay content, chlorophyll and water absorption features.

Green Vegetation Index

In order to mask vegetation it is often useful to calculate a green vegetation index. The most commonly used vegetation index is the Normalized Difference Vegetation Index (NDVI). The NDVI is defined and calculated with MapCalc as NDVI = (TM4-TM3) / (TM4+TM3) and can be used as threshold to mask vegetation in the TM bands.

NDVI

Multispectral classification

Techniques making use of training data sets are referred to as supervised classification. In order to train the classifier to perform a multi-spectral supervised classification you will have to sample the image to obtain a set of training pixels which serve as "an example of what to look for" with the classification algorithm. The output is a thematic map with the classes water, urban, limestone, kaolinite, hematite, green vegetation and dry vegetation.

Classified map of the Ronda-Malaga area

CitySurf Globe download for free

Citysurf is a server based 3D GIS software, developed by PiriReis. Citysurf is a new model for serving maps and interacting with the end user and has been created to model and serve raster data at high speed and low bandwidth. Databases such as high resolution satellite images and aerial images are combined with digital terrain models and vector-based geographical information. Citysurf can serve data over local networks or the internet. Each end user can manage and analyse geographical data through the Citysurf Globe interface with advanced authorization system incorporated in CitySurf.
       

CitySurf Globe is a family of Geography 2.0 Geographical Information System software, developed by PiriReis Bilişim Teknolojileri, known as a new model in mapping servers and interaction with the end user.

CitySurf Globe family models raster data, such as high resolution satellite images and aerial images, under high speeds using digital terrain model and vector geographical information systems and accordingly serves these via internet or local nets. Prepares geographical analyses and arranges the geographical data thanks to its interaction with the end user.

CitySurf Globe has an OpenGL-based viewer, which connects to the servers for streaming of content, elevation, satellite and/or airphoto imagery, roads, 3D buildings, points of interest, etc. This is similar to Google Earth, Microsoft Virtual Earth, and ArcGIS concepts.

It is able to:

• Fast transfer and secured data due to special data storage structure
• On the fly projection conversion which allows the usage of all sorts of data in different coordinate systems
• Perfect adaptation to different authorization needs of your company/organization with flexible authorization models for different user groups
• Creation of geographical objects (Point, Line, Polygon)
• Raster layer support in client and server (tiff, jpeg, png, KML 2.0)
• With the help of “Search scenario editor” various search windows could be formed and the results could be displayed according to the authorization level of the client
• Spatial filtering in search window
• Upload of geographic and spatial data by both Server and Client
• RDBMS supports Oracle SDO, PostGIS
• CitySurf Globe Client allows the user to prepare Thematic Maps (layers and columns which are going to be mapped thematically are defined by the server)
• Virtual trip on the image and movie recording
• Local GPS support
• Real time visibility and 3D profile analysis
• Data added by the Client can be sent via email to other users
• GPS tracking
• Reverse geocoding
• GeoRSS support
• GeoDynamic layer support

download

Opensource GIS software and their licenses

GRASS GIS 

GRASS GIS (Geographic Resources Analysis Support System) is a free, open source geographical information system (GIS) capable of handling raster, topological vector, image processing, and graphic data

GRASS is released under the GNU General Public License (GPL)

Quantum GIS 

Quantum GIS, également appelé plus simplement QGIS, est un système d'information géographique (SIG) libre multiplate-forme publié sous licence GPL.

Il gère les formats d’image matricielles (raster) et vectorielles, ainsi que les bases de données.

QGIS fait partie des projets de la Fondation Open Source Geospatial.

gvSIG

GvSIG est sans doute un des produits SIG (Système d'Information Géographique) bureautique le plus complet de l’offre open source. L’étendue de ses fonctions lui permet de rivaliser avec la plupart des produits standards du marché. Son interface très inspirée du logiciel ArcView 3.x rend son utilisation agréable et très intuitive. Son fonctionnement l'est également, puisqu'il reprend le principe d'extension destiné à ajouter des fonctionnalités à la version de base.*

GvSIG est publié sous licence GPL

Free and Open Source Software for Geospatial Information Systems

A range of related software packages can be used in addition to GeoNetwork opensource to deploy a full Spatial Data Infrastructure. These include Web Map Server software, GIS desktop applications and Web Map Viewers.

Below you will find some examples of open source software available for each categories.

Web Map Server software

• GeoServer (All)
• MapServer (All)
• MapGuide Open Source (Windows & Linux)
• Deegree (All)

GIS Desktop software

• GRASS (All)
• gvSIG (All)
• uDig (All)
• Quantum GIS (All)
• OSSIM (Windows & OSX)

Web Map Viewer and Map Server Management

• OpenLayers (All)
• MapBender (All)

Note
All = The Windows, Linux and Mac OS X operating systems.
read more about free mapping softwares

ENVI Geoservices and ArcGIS® Online – A New Paradigm for Image Analytics

The development and release of ArcGIS® Online by Esri® ushered in a new era of GIS access and availability. ArcGIS Online allows organizations and individuals to manage and display their map data on the internet via an easy-to-use interface. This has been useful for GIS professionals who have been overloaded with small requests for geographic information by allowing their users to self-serve data and maps that have been developed and published by the GIS analyst. It also allows users in the field to display ground truth information that may be collected as a series of GPS points or geographic notes. According to Esri, “In addition, non-GIS professionals, such as knowledge workers who have a need for GIS, now have a way to quickly create maps from the unstructured information they work with in spreadsheets and text files and share these maps with others who can access them on any device. This type of on-demand and self-serve mapping frees up GIS professionals from having to respond to constant requests for maps and instead concentrate on making and publishing authoritative information products.” (Esri, June, 2012)

Along with map and display capabilities, ArcGIS Online comes equipped with the ability to conduct geo-processing tasks, or geoservices. Esri currently provides geocoding and network analysis geoservices, among others. Users with an ArcGIS for Server instance can also publish their own geoservices and models from the Esri software suite and consume them via ArcGIS Online. This means that customized workflows can be distributed via ArcGIS Online for consumption by non-technical users in the field. These services can be also be integrated into custom interfaces developed using the ArcGIS Web Mapping API’sor the ArcGIS Mobile Runtime SDK.

An ENVI Change Detection Geoservice in ArcGIS Online

Exelis Visual Information Solutions has worked very closely with Esri for years to develop interoperable solutions to leverage advanced image analytics from ENVI from within the ArcGIS ecosystem. Along with both desktop and server side interoperability, ENVI is now able to take advantage of the ArcGIS Online platform to expose ENVI geoservices in the cloud. Implemented using the ENVI Services Engine and the ArcGIS API for JavaScript, the app queries and consumes Landsat image services to run a number of different analysis tasks. Results are delivered back to the thin client as a visual representation, with links to download the processed datasets available if needed. Not only can this type of implementation run analysis and deliver results on remote data, the time-aware nature of the Landsat Image Service allows for time aware analysis to be conducted such as change detection, or in this case, NDVI analysis over time.

Displaying an NDVI Result from an Image Service in a Thin Client

This example of ENVI image analysis being run on image service data from the ArcGIS online environment is a snapshot of the future. In the same way that the storing and viewing of map products has migrated to the internet, so too will the analysis of large data be executed on large servers in remote locations and consumed via thin clients and mobile apps. What do you think? Are thin clients such as ArcGIS Online that consuming remote data and analysis functionality the future of GIS? Do you see a need in your organization for web-deployed analytics?
Read more

Connecting to OS OnDemand web map service (WMS) through ESRI software

OS OnDemand is Ordnance Survey's web map service, delivering the most up to date map data directly into an organisation from our database. It provides a simple way to access our trusted mapping and local information, giving you a single view of the data across your entire organisation. So it doesn't matter if you're sat side by side or at opposite ends of the country, you can be sure you're viewing the same information. OS OnDemand allows you to quickly pan and zoom, letting you view the mapping in great detail, as well as combining data that's relevant to your business.

OS OnDemand is compatible with most GIS software packages and these videos show you how to connect to the service through some of those packages including ESRI.

To use the software, the first step needed is to map to OS OnDemand through ArcCatalog. Once in ArcCatalog you will need to find the GIS server and then add WMS server. Copy in the url given to you as part of the welcome information so that you can access OS OnDemand and then click get layers. You will then be prompted for a username and password. The available layers will now be shown. The OS OnDemand WMS will now appear on the list of GIS servers. You can use the properties field to change the name of the WMS if you want.

You will now need to open ArcMap to view the OS OnDemand WMS data feed. You will be prompted to add the map layers by selecting the OS OnDemand server.

You will then be able to:
• pick what datasets you want to show
• zoom into the map to see your different map layers at different scales.
• lay your own information, such as points lines and features on top of the map.
• change how the information is presented using your GIS functionality.

IRAQ - download free spatial Data

IRAQ - 1:250K Geological Vector Data

Once again our talented procurement department has done its job. This time they bring us a gem of data in the form of 1:250K geological vector data over the entire country of Iraq. It is truly an astonishing feat to have this data on hand and the benefits it can bring to our clients are endless.

1:250K Geological Vector Index Map - Iraq

Scale: 1:250,000

Coverage: Complete, 35 sheet series

Publish years: 1995-2008

Publisher: State Establishment of Geological Survey and Mining (GEOSURV), Baghdad, Iraq.

Language: English language

Also available: Digital explanatory notes for each map sheet (Word or .pdf format) also in English.

Formats available:

Paper

Raster

Georeferenced raster

GIS/Vector

1:250K Geological Vector Data - Iraq

The maps that make up this dataset are extremely rare and difficult to obtain. We have gotten the hard part out of the way and now they are easily available to you.

irak, free, vector, spatial data, download, shape, shp, imagery,

About the FME Spatial Data Transformation Platform

Achieve total spatial data mastery with FME

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Easily transform data to use and share

The FME technology platform makes it easier to handle the diverse range of spatial data formats and evolving standards make interoperability such a challenge. With a unified view of your spatial and non-spatial data, you can better meet business goals and required standards, generating new insight across the organization. Solve more spatial data transformation challenges than with any other technology:

• Only FME allows you to transform more than 300 spatial and non-spatial formats.
• Only FME gives you unlimited flexibility to restructure, reformat, and integrate your spatial data.
• Only FME answers the complete range of spatial data interoperability challenges with a single platform.

Choose FME, the most proven technology

Today, FME is the dominant technology for spatial data transformation. It powers our FME Desktop and FME Server software and the solutions of more leading spatial data application vendors than any other technology. It's used by tens of thousands of customers worldwide across a wide range of industries.

The need for GIS automation

1.1.1 The need for GIS automation

A geographic information system (GIS) can manipulate and analyze spatial datasets with the purpose of solving geographic problems. GIS analysts perform all kinds of operations on data to make it useful for solving a focused problem. This includes clipping, reprojecting, buffering, merging, mosaicking, extracting subsets of the data, and hundreds of other operations. In the ArcGIS software used in this course, these operations are known as geoprocessing and they are performed using tools.

Successful GIS analysis requires selecting the right tools to operate on your data. ArcGIS uses a toolbox metaphor to organize its suite of tools. You pick the tools you need and run them in the proper order to make your finished product.

Suppose you’re responsible for selecting sites for video stores.  You might use one tool to select land parcels along a major thoroughfare, another tool to select parcels no smaller than 0.25 acres, and other tools for other selection criteria.  If this selection process were limited to a small area, it would probably make sense to perform the work manually. 

However, let’s suppose you’re responsible for carrying out the same analysis for several areas around the country.  Because this scenario involves running the same sequence of tools for several areas, it is one that lends itself well to automation. There are several major benefits to automating tasks like this:

• Automation makes work easier. Once you automate a process, you don't have to put as much effort remembering which tools to use or the proper sequence in which they should be run.
• Automation makes work faster. A computer can open and execute tools in sequence much faster than you can accomplish by pointing and clicking.
• Automation makes work more accurate. Any time you perform a manual task on a computer, there is a chance for error. The chance multiplies with the number and complexity of the steps in your analysis. In contrast, once an automated task is configured, a computer can be trusted to perform the same sequence of steps every time.

ArcGIS provides three ways for users to automate their geoprocessing tasks. These three options differ in the amount of skill required to produce the automated solution and in the range of scenarios that each can address.

The first option is to construct a model using Model Builder. Model Builder is an interactive program that allows the user to “chain” tools together, using the output of one tool as input in another. Perhaps the most attractive feature of Model Builder is that users can automate rather complex GIS workflows without the need for programming. You will learn how to use Model Builder early in this course.

Some automation tasks require greater flexibility than is offered by Model Builder and for these scenarios it's recommended that you write scripts.  The bulk of this course is concerned with script writing.

A script is a program that executes a sequential procedure of steps. Within a script, you can run GIS tools individually or chain them together. You can insert conditional logic in your script to handle cases where different tools should be run depending on the output of the previous operation. You can also include iteration, or loops, in a script to repeat a single action as many times as needed to accomplish a task.

There are special scripting languages for writing scripts, including Python, JScript, and Perl. Often these languages have more basic syntax and are easier to learn than other languages such as C, Java, or Visual Basic.

Although ArcGIS supports various scripting languages for working with its tools, ESRI emphasizes Python in its documentation and includes Python with the ArcGIS install. In this course we’ll be working strictly with Python. You’ll learn the basics of the Python language, how to write a script, and how to manipulate and analyze GIS data using scripts. Finally, you’ll apply your new Python knowledge to a final project, where you write a script of your choosing that you may be able to apply directly to your work.

The third option available to ArcGIS users looking to automate geoprocessing is to build a solution using ArcObjects, the programming building blocks used by ESRI’s own developers to produce the ArcGIS desktop products. With ArcObjects, it is possible to customize the user interface to include specific commands and tools that either go outside the abilities of the out-of-the-box ArcGIS tools or modify them to work in a more focused way. ArcObjects programming and interface customization are outside the scope of this course, but are covered in the GIS Application Development course, GEOG 489.  GIS customization with ArcObjects can be an advanced endeavor, and learning a scripting language like Python is a good way to prepare yourself by learning basic programming concepts.

The tools that you run in ModelBuilder and Python actually use ArcObjects "under the hood" to run GIS functions; however, the advantage of Python scripting with ArcGIS is that you don't need to learn all the ArcObjects logic behind the tools. Your job is just to learn the tools and how to run them in the appropriate order to accomplish your task.

This first lesson will introduce you to concepts in both model building and script writing. We’ll start by just getting familiar with how tools run in ArcGIS and how you can use those tools in the ModelBuilder interface. Then, we’ll cover some of the basics of Python and see how the tools can be run within scripts.

Lesson 1 checklist

Lesson 1 checklist

This lesson is two weeks in length. (See the Calendar in ANGEL for specific due dates.) To finish this lesson, you must complete the actvities listed below. You may find it useful to print this page out first so that you can follow along with the directions. 

1. Download the Lesson 1 data and extract it to C:\WCGIS\Geog485\Lesson1 or a similar path that is easy to remember.
2. Work through the online sections of Lesson 1.
3. Complete Project 1, Part I and submit the deliverables to the course drop box.
4. Complete Project 1, Part II and submit the deliverables to the course drop box.
5. Complete the Lesson 1 Quiz.

spatial data

Also known as geospatial data or geographic information it is the data or information that identifies the geographic location of features and boundaries on Earth, such as natural or constructed features, oceans, and more. Spatial data is usually stored as coordinates and topology, and is data that can be mapped. Spatial data is often accessed, manipulated or analyzed through Geographic Information Systems.

GIS Spatial Data Types

GIS Spatial Data Types

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In GIS, there are 2 basic spatial data types representing the real world:
Raster and Vector

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The Real World 

In this example, our landscape consists of

• rolling hills
• grassland
• lake
• rivers
• forest stands
• marsh

It can be represented as a series of raster layers and/or vector layers.

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Raster Data
In the raster data model, land cover is represented as:

• single square cells

Each cell will have a value corresponding to its land cover type.

Raster data are good at:

• representing continuous data (e.g., slope, elevation, chemical concentrations)
• representing multiple feature types (e.g., points, lines, and polygons) as single feature types (cells)
• rapid computations ("map algebra") in which raster layers are treated as elements in mathematical expressions
• analysis of multi-layer or multivariate data (e.g., satellite image processing and analysis)
• hogging disk space

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Vector Data
In the vector data model, features on the earth are represented as

• points
• lines / routes
• polygons / regions
• TINs (triangulated irregular networks)

Vector data are good at

• accurately representing true shape and size
• representing non-continuous data (e.g., rivers, political boundaries, road lines, mountain peaks)
• creating aesthetically pleasing maps
• conserving disk space

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Different types of data are
stored in different
file formats.

 

images © ESRI

Software : Esri CityEngine Advanced 2011.2 with Document

Esri CityEngine Advanced 2011.2 with Document | 1.03 GB

Esri CityEngine is a stand-alone software product that provides professional users in architecture, urban planning, entertainment, GIS and general 3D content production with a unique conceptual design and modeling solution for the efficient creation of 3D cities and buildings.

About Ersi

When Esri was founded in 1969, we realized even then that geographic information system (GIS) technology could make a difference in society. Working with others who shared this passion, we were encouraged by the vast possibilities of GIS.

Today, our confidence in GIS is built on the belief that geography matters—it connects our many cultures and societies and influences our way of life. GIS leverages geographic insight to ensure better communication and collaboration.

As you explore our Web site, you'll discover how our customers have obtained the geographic advantage by using Esri software to address social, economic, business, and environmental concerns at local, regional, national, and global scales. We hope you will be inspired to join the Esri community in using GIS to create a better world.

Features

- GIS Data Support
CityEngine supports the use of geospatial data such as Esri Shapefile, File Geodatabase (GDB), KML, and OpenStreetMap (OSM), allowing you to work with existing GIS features – like parcels, building footprints and street center lines – when constructing 3D urban landscapes.
- Industry-Standard 3D Formats
CityEngine works with many 3D formats, including Collada, Autodesk® FBX, DXF, 3DS, Wavefront OBJ, and e-on software Vue. Constructed 3D content can also be exported out to Pixar's RenderMan® RIB format and NVIDIA's mental ray MI format.
- Rule-based Modeling Core
Procedural modeling offers the ability to generate and texture detailed 3D buildings and street geometries out of 2D data. Many example rules are included with CityEngine and new custom rules can be authored using your own textures and 3D assets.
- Parametric Modeling Interface
CityEngine exposes a set of interactive controls to adjust rule parameters, allowing experimentation with model construction settingssuch as the height, roof form or age of a building. Parameter modifications will automatically invoke regeneration of the 3D model.
- Dynamic City Layouts
A toolset is provided to design and edit urban layouts with streets, blocks and parcels. Street construction or block subdivision is controlled via parametric interfaces, giving immediate visual feedback.
- Facade Wizard
Create rules from an image or textured mass model with an easy-to-use facade authoring tool. The resulting facade rules are size-independent, contain level-of-detail and can be extended.
- Map-Controlled City Modeling
Parameters of buildings and streets can be controlled globally using maps ( e.g., land use), allowing for easy city modeling and quick changes. Terrains can be imported, aligned, and exported.
- Street Networks Patterns
CityEngine offers unique street growth tools to quickly design urban layouts. Street patterns such as grid, organic or circular are available, and the topography of the terrain is taken into account.
- Reporting (BIM for Cities)
Customized rule-based reports can be generated to analyze urban designs, including the calculation of important urban propertiessuch as GFA (Gross Floor Area), FAR (Floor Area Ratio), and so on. Reports are updated automatically and instantaneously.
- Python
Streamline repetitive or process-specific tasks with the integrated Python scripting interface, such as, writing out arbitrary meta-data or instancing information for each building, import FBX cameras etc.
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