Lab #10 Data Entry

Stefanie Wieschalla

Geog 206

Part1:

1. Each map has a different level of map generalization. However, one would have more problems with feature generalization and omission in small scale maps because they cover bigger areas and hence show less detail.

2. Snapping, in the context of digitizing can be understood as a process that automatically sets nearby points to have the same coordinates. It further relies on snap distance, which can be interpreted as a minimum distance between features. The practice of snapping is important given that it when used properly, it reduces the number of undershoots and overshoots. Hence closed polygons or intersecting lines are easier to digitize accurately and efficiently.

 3. COGO is short for coordinate geometry, a process that may be used to calculate station coordinates that are part of surveys or otherwise known as survey coordinates. It generally consists of a starting point, a station, and a list of directions, bearings, and distances to subsequent stations. The COGO defines a connected set of points from the starting station to each subsequent station.  

Part 2:

Exercise A

Q. The feature class type for Springs is point.

Exercise B

Parcel Editing Screen Shot

Lap #9b More Practice with Spatial Analysis

Stefanie Wieschalla

Geog 206


 

1. The state of Iowa contains of 99 counties.

2. Fulton contains the largest number of people in Georgia, as of the year 2001.

3. There are 39 cities, with populations between 10,000 and 49,000, that are located within the State of Washington.

4. The interstates in LA County are all together 4105.56 miles long.

5.

6. Within LA County there lie 4115.74855 acres of urban area.

7. There are 522 zip codes that have their centroid in LA County.

8.

 

9. There are two Native American Indian Reservations, which are Kitigan Zibi Indian Reserve and Akwesasne Indian Reserve 15 that lie within 75 miles of the City of Thurso, Canada.

10.

Lap #9a Introduction to Spatial Analysis

Stefanie Wieschalla

Geog 206

Part 1:

1. A spatial scope is the size or area of the input data utilized to find out the values at output locations. There are three types, which are local, neighborhood, or global operations. All reflect somehow the extent of the source area used to reveal the value at a given output site. Local operations use only the data at one input location, where neighborhood operations use data both at input location as well as nearby locations to determine output value. Yet, global operations utilize data values from the entire layer to determine each output value.

2. The two types of Algebra used in queries are set algebra and Boolean algebra. The difference exists in the fact that set algebra uses the operations less than, greater than, equal to, and not equal to, where Boolean algebra utilizes the conditions or, and, and not to select features. Selection conditions are often formalized using set algebra given that they meet one to several conditions or criteria. For example, two conditions are applied and the features that satisfy both conditions are included in the selected set like growing fruits as well as vegetables is taken place in northern plus southern California. In contrast, Boolean algebra is most often used to combine set algebra conditions and create compound spatial selections. A good example would be the expression using a Boolean AND, with two arguments for the expression. Thus, features are selected if they satisfy both arguments as for example income is higher than 5,000 a month and they are living in a house.

3. The different types of spatial selection operations are first adjacency, which are used to identify features that “touch” other features and second containment, which identifies all features that contain or surround a set of target features.

Part2:

4. Yes, there is a feature dataset called Los Angeles.

5. There are four feature classes present named: PtDumeQuad, Vegetation, Wetlands and Wetlands_Project

Part3:

6. There exist 10896 features in the vegetation feature class.

7. Now, after running the dissolve operation, there exist only nine features in the new VegCoc feature class.

8. In this new VegCov_Clip feature class there exist now 8 features.

Part4:

9. There were 404 wetland features selected in the attribute table.

10. There were 123 features selected.

11.

Lab #8 Database Management & Queries

Stefanie Wieschalla

Geog 206

Part 1:

1. The primary functions of a database management system is organizing and manipulating data. This includes data independence, which makes it possible to make changes in the database structure in ways that are evident to any use or program. Furthermore, it provides for multiple user views and hence DBMs can reformat data without human intervention to meet exact input requirements of different users. Lastly, these systems also allow centralized control and maintenance of important data. 

2. In a one-to-one relationship, a row in table A can have no more than one matching row in table B, and vice versa. A one-to-one relationship is created if both of the related columns are primary keys or have unique constraints. However, this type of relationship is not common because most information related in this way would be all in one table. A one-to-many relationship is the most common type of relationship. In this type of relationship, a row in table A can have many matching rows in table B, but a row in table B can have only one matching row in table A. For example, the Publishers and Titles tables have a one-to-many relationship: each publisher produces many titles, but each title comes from only one publisher. A one-to-many relationship is created if only one of the related columns is a primary key or has a unique constraint.

3. Relational databases are so popular because they are more flexible than most other design models. The organization is very straightforward and thus east to learn, understand and implement when compared to other database designs. Besides that, table structure does not restrict processing or queries. It can lodge a wide range of data types and therefore it is not necessary to know in advance the kind of queries, sorting, and searching that will be performed on the database.

Part 2:

4.

a. The Data Type of the LAN_USE field in the Landuse feature class is text since it is left justified and makes use of special characters as for instance dashes and spaces.

b. The Data Type of the LAN_USE field in the LanduseInfo.dbf table is also text.

5.

a. The new fields that have been joined are all the columns that were in the stay alone tables, which are: the general column, the description column, the type column, a square miles column, an acres column, a shape length column, and finally a shape area column.

e. There exists 92236.771795 total acres of open lands in this new feature class. 

f.

g.

Lap #7 Map Design & Text

Stefanie Wieschalla

Geog 206

Part 1:

Chapter 7:

1. The information used for dynamic labels come from the attribute table of a specific layer.

2. The most efficient way to show only 3 city names is by using the label tool on the Draw Toolbar. This tool allows you to label features one at a time by clicking them. They can be placed wherever you want and changed individually.

3. Yes, you can manually adjust the position of dynamic labels by moving the mouse pointer over the selected text. The cursor changes to a four-headed arrow. Now you can drag the text to your convenience, releases the mouse button and click an empty are to unselect the text.

4. To adjust graphics the Select Elements tools needs to be selected.

5. There are two types of geodatabase annotation. Standard annotation is geodatabase annotation that does not have a maintained link to any features. The other type, feature-linked annotation, is a special type of geodatabase annotation that is directly linked to features and has special updating behavior when the linked features are updated.

Chapter 18:

1. It is TRUE, you can create your own ArcMap templates.

2. Yes, you can save it as an .mxd file.

3. You can access map templates by starting ArcMap, when you do so a dialog box opens up. Click to use a template option, and then click OK. A new dialog box opens. All the templates that come with ArcGIS can be found here. Another way to access map templates is by directly accessing the folder where the templates are stored. ArcMap custom templates are stored in the /Bin/Templates folder of your ArcGIS installation path.                                           

4. You can do this by right-clicking a layer in the table of contents and click properties. The layer properties dialog box opens. Click the symbology tab. In the show box, click features and then single symbol. Then click on the Symbol field and a symbol selector dialog box opens. Scroll down until you find the star symbol, click on it. Then under the options field you can further change the color to purple and the size of the star to 12. Click OK.

5. You can change the color of a graphic scale by right clicking on a layer. On the context menu, click properties. In the properties dialog box, click the Symbol tab. Click the color square. On the color palette, click the color of your choice. Then click OK and the new color is applied. Another way to simply change color is by right clicking on the symbol of the layer in the table of contents. The color palette opens and you can change the color to the color of your choice.

Chapter 19:

1. Before setting up your map layout, you should always choose the dimensions and the orientation of the map.

2. The scale is different in the data view versus the layout view because when you resize a data frame, ArcMap automatically adjusts the map extent and display scale.

3. The three customization options available for the scale bar are: Scale and Units, Numbers and Marks and Format.

4. It is important to use the 1:1 button because it forces the layout to zoom to its actual size and you can now see the map at the resolution it would have on a printed page. You can no longer see the entire layout.

5. Graphics can be placed either in layout view, along with cartographic elements such as scale bars and north arrows, or in data view so the graphics resize with your data as you change the extent of your map. When you add graphics to your data view and switch to layout view, you will always be able to see these added graphics in layout view. However, you cannot change them, for example move text around. However, when you add graphics in layout view and you then switch to data view, these newly added features will not appear, as for example the north arrow or the scale bar.

Part 2:

Q1. Choropleth maps show numerical data aggregated over predefined regions, such as countries or states, by coloring or shading these regions. Polygons are often based on politically defined feature. This will further yield a display that puts visual emphasis on the largest area units of the map.

Q2. The benefits of layer files are enormous. First of all, a layer references the data stored in geodatabases, coverages, shapefiles, rasters, and so on, rather than actually storing the geographic data. Thus, a layer always reflects the most up-to-date information in your database. A layer will not draw on your map unless you also have access to the data source on which the layer is based. Secondly, layers have a number of properties you can work with and set. You can right-click a layer in the table of contents and click Properties to view the Layer Properties dialog box, where you can set symbology, labeling, drawing rules, and other options. For example, you can specify that streams are drawn with all blue lines, parcels are drawn based on their land-use code, parks are drawn using a green pattern fill and are labeled with the park name, digital elevation is portrayed as a shaded relief, and so on. In addition, other properties include defining the scales at which they can draw, which features to draw from the data source, where that data is located in your database, attribute properties, joins, and relates for working with the tabular information. Lastly, layers can be saved to a file on disk (.lyr) so they can be shared and reused without sharing the entire map. When you save a layer to disk, you save everything about the layer, such as the symbolization and labeling. When you add a layer file to another map, it will draw exactly as it was saved. Others can drop those layers onto their maps without having to know how to access the database or classify the data; this can be helpful when sharing data stored in a multiuser geodatabase with nontechnical staff members. You can share layers over the network as well as e-mail layers, along with the data, to people or enclose the layer within the data's metadata.

Q3. Layer files (layer_name.lyr) include all map display properties for symbolization and labeling. However, layers do not usually contain the actual datasets. Instead, they typically reference a data source that resides in another location. However, a map layer and its data contents can be saved and shared using a layer package. A layer package is saved as a special file (layer_name.lpk) that contains the map layer, a copy of its data, and an XML file that has a brief description of the layer. Layer packages contain all the information necessary for users to put them to work in their own ArcGIS software installation. They are supported in ArcMap, ArcGlobe, and ArcGIS Explorer. Generally, layer packages make it easy to share your map layer display along with the underlying data with other users. For example, users of ArcGIS Explorer can add a new layer to their maps and easily begin using the information that you shared with them as a layer package.

Q4. The population of Long Beach for the year 2000 is 461522.

Q5. The population of Los Angeles for the year 2000 is 3694820.

Q6. There are three types of hyperlinks:

• Document: When you click a feature with the Hyperlink tool, a document or file will be launched using the application with which that file type is currently associated.
• URL: When you click a feature with the Hyperlink tool, a Web page will be launched in the default browser.
• Macro: Visual Basic macros are not supported in ArcReader. The macros will not be available in the published map.

Part3:

Lab #6 Symbolization and Classification

Stefanie Wieschalla

Geog 206

Part 1:

1. Symbology can be influenced by scale given that in some maps, cities can be indicated by circles or as polygons and hence the more detail the scale provides, the bigger will those symbols appear. For example cities in a scale of 1:200,000 represented as a polygon will appear differently and larger than cities in a scale of 1:13,000,000 represented as a circle.  

2. One way to access a layers symbol colors so that they can be changed is by clicking the symbol for a particular layer in the table of contents. The Symbol Selector dialog box opens. The options frame on the right allows you now to pick colors. Another way to access a layers symbol colors is by simply right clicking on the layer, choosing the layers properties option and then, when the properties dialog box opens, you need to click on the symbology tab. Now you can change color.

3. One would access the graduated symbols classification option by double clicking the layer name of one’s choice to open the layer properties dialog box. Then one needs to click on the symbology tab. In the show box, click Quantities. In the Quantities column one can find the option “graduated symbols”.

4. Five other symbology styles (in addition to ‘Conservation’) that are available to customize your features are for example: Crime Analysis, Caves, Survey, Weather and Forestry.

5. One could permanently save layer symbology for a later use by right clicking the layer of one’s choice in the table of contents and then click save as layer file. In the save layer dialog box, navigate to the folder you were working with, accept the default name and then click save.

6. Pyramids can help raster data display faster by retrieving only the data at a specified resolution that is required for the display. With pyramids, a lower-resolution copy of the data displays quickly when drawing the entire dataset. As you zoom in, levels with finer resolutions are drawn; performance is maintained because you're drawing successively smaller areas. The database server chooses the most appropriate pyramid level automatically based on the user's display scale.

7. One would quickly and temporarily change a layer name to aid display in the Table of Contents by clicking once the layer you want to rename, wait a moment and then click again. Now the name is highlighted and the layer is ready to be renamed.

8. Dividing one attribute by another to find the ration between them is referred to as normalization. It is mostly used to calculate density.

9. Dot density maps could be misleading because the dot placement is random within each country and hence the arrangement of dots on a map will not match the graphic exactly. This is especially confusing when focusing on small areas.  

Part2:

Lab #5 Data Source and Management

Stefanie Wieschalla

Geog 206

Part 1:

1. The advantages of using digital spatial data are that it is possible to directly transfer them to other digital devices and GIS systems, where they may be further processed. Digital formats provide a more efficient processing of data. Besides that, it is the easiest, quickest and least expensive source of spatial information. Disadvantages are that the data may not be in the format you want it to be so you need to convert it. Also, global data sets do not really exist because only few governments collect spatial data in the same way or with the same attributes. Data reduction or documentation methods may be different across national boundaries. Furthermore, digital spatial data is only partly available to the public and quality is not always good.

2. The most important question to ask before using already-developed spatial data is regarding its source. Is the data accurate? Who produced it? What are the source materials and what do they contain? Furthermore it is significant to ask if the data is free and if the data matches your theme and scale. Is it appropriate?

3. DOQs differ from regular photographs because they are actually scanned photographic images that have been corrected for distortions due to camera tilt, terrain displacement, and other factors. These corrections yield photographers that are planimetrically correct are very similar to large-scale topographic maps.

4. Digital Raster Graphics (DLGs) have been mostly produced from USGA series maps and most features on these maps have been recorded in DLGs so there is a close correspondence between DLGs and USGS series maps. Hence DLGs are vector representations of most features portrayed on USGS national series maps. They are available by map series designation, for example 1:2 million DLGs are available that contain the data included on 1:2 million scale maps. DLGs for 1:100,000 and 1:24,000 scale maps are also available. The extent of an individual DLG typically corresponds to the extent of the map series.  The materials contain boundaries, hydrography, roads and hypsography.

The U.S. Census Bureau produces and maintains database systems to support the national census. This system is known as the Census Tiger system. It links geographic entities to census statistical data on population size, age, income, health, and other factors. The units are typically polygons classified by roads, streams, political boundaries, or other features. These source material files define line, landmark and polygon features in a topologically integrated manner. Polygon features for example include census tabulation areas such as census block groups and tracts. These files contain information to identify street address labels.

The National Land Cover data has been produced by the USGS and other agencies and organizations to meet a wide variety of spatial needs. The data source materials are based on the interpretation of t1970s and early 1800s aerial photographs. Photographs were taken at a range of scales and they contain a variety of land cover features as fine grain features, including road corridors and small lakes.

5. NED can generally be seen as an improvement over previous sources, in particular the DEM because it is a high resolution, seamless data source. Previous high resolution DEM data from the USGS were provided only over small areas with fixed boundaries. It was very time consuming to assemble these titles into a mosaic, when DEMs where required for large areas. Artifacts such as gaps or discontinuities were sometimes introduced at edges, and tiles were sometimes produced using different datums, projections or units. A seamless NED data set avoids these problems. Furthermore, NED is a progress in quality of slope, aspect, shaded-relief, and drainage information that may be derived from the elevation data.

Part 2:

2.

a.) Basemap and Hydrology are the names of the feature datasets in the geodatabase.

b.) NHDFlowline, NHDPoint, NHDWaterbody and Watersheds are the names of the feature classes in the hydrology dataset.

c.) NHDFlowline is a polyline layer. NHDPoint is a point layer. NHDWaterbody and Watersheds are both polygon layers.

3.

a.) topoq24.shp is a vector layer.

b.) The GIS Data format of topoq24.shp is a shapefile.

c.) Yes, there is metadata associated with topoq24.shp.

d.) The GIS Data format of NHDFlowline is the ArcGIS Geodatabase.

e.) Yes, there is metadata associated with NHDFlowline.

f.) Three examples of the keywords used to describe the NHDFlowline are: Hydrography, Stream and Lake.

g.) The NHDFlowline layer was created by: Earth Science Information Center, U.S. Geological Survey.4.

a.) Yes, there is still metadata associated with the layer (NHDFlowline.shp).

6.

b.) The USGS_QD-ID for Canoga park is 34118-B5.

7. The DOQQ is black and white.

8. Screenshot of CSUN campus



CSUN Campus

 10. Screenshot of expanded folder/file structure in ArcCatalog



12.

a.) The lacounty_lu01.shp layer has now a red exclamation point next to the grayed-out check box.