Let’s consider this process and try to build a couple Some Definitions Let’s consider this process and try to build a couple

Why are definitions important? If you can make your own then It shows you understand the concept You are able to explain it to others (not parrot) You should be able to illustrate why the concept is important

Where are definitions used? Everywhere in life Those in education spend their careers defining Those working in NGOs are always educating Even clerks at Lowes need to be able to define things

Definition Building Divide text or powerpoint material into bullets Rank them by order of importance Translate these points into sentence(s) using your own words. Insert examples in the definition

Electronic Atlas Maps on the web, disk, CD,... Here I have already divided things into bullets Maps on the web, disk, CD,... Static -- what you see is what you get Descriptive No analytical tools available in software Data Storage Device Much like paper maps store data in fixed static format Limited Goals/Limited Uses in mind May have unexpected/unused information 5 E-Atlas 5

Image data More typical definition in prose. Needs to be abstracted into bullet points Image data An image is a graphic representation or description of an object that is typically produced by an optical or electronic device. Some common examples of image data include remotely sensed data, such as satellite data, scanned data, and photographs. Image data is a form of raster data where each grid-cell, or pixel, has a certain value depending on how the image was captured and what it represents. For example, if the image is a remotely sensed satellite image, each pixel represents light energy reflected from a portion of the Earth's surface. If, however, the image is a scanned document, each pixel represents a brightness value associated with a particular point on the document. With ArcView you can display image data and feature-based spatial data together in views. ArcView can display and print black and white, grayscale, pseudocolor and true color images. You can also include them in a layout. To add an image to a view, see Adding a theme to a view. To change the way an image looks and to derive additional information from an image you can edit an image's legend. Images are often used as the background to views, with spatial data being drawn on top of them. Themes representing images are therefore normally moved to the bottom of the view's Table of Contents, so that they are drawn on the view first. The main difference between image data and feature-based spatial data is that images do not contain attribute data about the features they show.

Feature Data In ArcView, features are stored as vector data and their attributes are stored in tables known as attribute tables. Each class of features is stored in a shapefile and has its own attribute table. Attribute tables contain one record for each feature of that class in the coverage. Points: Points represent features found at discrete locations, such as telephone poles, wells and mountain peaks. Arcs: Arcs represent linear features such as streams, streets and contours. Polygons: Polygons represent areas enclosed by specific boundaries, such as countries, states, land parcels and soil types. This looks a little less intimidating

In Class Exercise Break class into groups Determine and rank main points for given definition From this write a definition in your own words Type this in as an MS Word doc and save in J:\saldata\SAL_temp\Egeo250\Definitions

Imagefile Imagefiles store raster data but no attributes or entities Can be organized in a number of ways depending upon the particular image format. giff tiff jpeg… Typically, the image data file contains a header record that stores information about the image -- number of rows and columns in the image, the number of bits per pixel (or raster), the color requirements and the georeferencing information. There are four types of images: monochrome (one color usually black on white) pseudocolor grayscale (shades of black on white) true color/multiband

Image File Raster Data no atts Blk wht gray… formats details In simplest form

Shapefile Shapefiles store feature data (vectors) Entities Attributes Geocodeshic features. Required files .shp - the file that stores the feature geometry.(points, lines, or polygons and geocodes) .shx - the file that stores the index of the feature geometry. .dbf - the dBASE file that stores the attribute information of features. (descriptors) Optional files A number of optional files also exist, but will not be discussed here A major difference between shapefiles and image files is the former has attributes attached to entities, the latter has no attributes or entities

Shapefile(s) Vectors…. Attributes… Pts lines ploy… In simplest form Vectors…. Attributes… Pts lines ploy… Details file 3 min…

Now you finish Turn these points into complete sentences Use you own words Add illustrations

Define Geography ge·og·ra·phy (j-gr-f) n. pl. ge·og·ra·phies 1. The study of the earth and its features and of the distribution of life on the earth, including human life and the effects of human activity. 2. The physical characteristics, especially the surface features, of an area. 3. A book on geography. 4. An ordered arrangement of constituent elements: charting a geography of the mind. Geography is a discipline concerned with: Why things are located where they are. Is a science that deals with two questions: Where are things – Looks at and for PATTERNS; Why/How things are at a location – Looks at and for PROCESSES