Wednesday, November 24, 2010

Lab 10

I. Read Bolstad Chapter 4 and answer the following questions based on the reading and lecture.

1. Would you have more problems with feature generalization and omission in large or small scale maps? Why?
You would have more problems with feature generalization and omission on a small scale map. This is because there are fewer details on a small scale map (it is zoomed out more). A large scale map, on the other hand, is zoomed in more and due to this there are more details. In addition, on large scale maps less generalization is needed.

2. What is snapping in the context of digitizing? Why is snapping important (i.e. what does it help avoid)?
Snapping is a process of automatically setting nearby points to have the same coordinates. This helps to reduce the number of undershoots and overshoots while digitizing.

3. What is COGO and how does it relate to coordinate surveying?
COGO stands for coordinate geometry, and it is spatial data that consist of a starting point with a list of directions and distances to subsequent stations.

II. AFTER completing Ormsby Chapters 14 -17, complete the following exercises.
EXERCISE A

Q: What is the feature class type (point, line or poly) for Springs?
Point




Wednesday, November 3, 2010

Lab 9b

1. How many counties does the State of Iowa contain? (1 pt)
 There are 99 counties in Iowa.

2. Which county in Georgia contains the largest number of people, as of the year 2001? (1 pt)
Fulton contains the largest number of people in 2001.

3. How many cities, with populations between 10,000 and 49,000, are located within the State of Washington? (1 pt)
There are 39 cities in Washington that have a population between 10,000 and 49,000.

4. How many miles long are all of the interstates in Los Angeles County? (1 pt)
The interstates in Los Angeles County are 4,105.56 miles long.

5. Simplify the UrbanBoundaries feature class so that only the urban areas of Los Angeles County are visible (Hint: you must use one of the overlay functions). Create a new feature class and save it into the LosAngeles dataset using the name LA_Urban. Include a screenshot of this new layer with your assignment. (2 pts)























6. How many acres of urban area lie within Los Angeles County, based upon your results from question #5? ( 1 pt)
There are 1,441,652.796875 acres of urban area within Los Angeles County.

7. How many zip codes have their centroid in Los Angeles County? (1 pt)
There are 522 zip codes that have their centroid in Los Angeles County.

8. Create a layer displaying the provinces of Canada using the data provided to you in the Canada feature dataset. Save this new layer under the Canada feature dataset using the name Provinces. Include a screenshot of this new layer with your assignment. (2 pts)



9. Which Native American Indian Reservations lie within 75 miles of the City of Thurso in Canada? (1 pt)
Both Kitigan Zibi Indian Reservation and Akwesasne Indian Reservation lie within 75 miles of the city Thurso.

10. Open your final and complete geodatabase in ArcCatalog. Make sure all of the feature datasets and feature classes are viewable. Capture a screenshot of the geodatabase and include this screenshot with your assignment. (1 pt)

Lab 9a

I. Read Bolstad Chapter 9 and answer the following questions based on reading and lecture.

1. What is spatial scope and what are the three types?
Spatial scope is the extent or area of the input data that are used in determining the values at output locations. There are three different spatial operations that act upon the input of the geographic or attribute data: local, neighborhood, and global operations. Local operations only use data at one input location to determine the value of the corresponding output location. Neighborhood operations use data from both an input location and the adjacent locations to determine the output value. Global operations use data values from the entire input layer to determine each output value.

2. What are the two types of Algebra used in queries? Give an example of each.
Set algebra and boolean algebra are the two types of algebra used in queries. Set algebra uses operations that include less than (<), greater than (>), equal (=), and not equal (<>). Some examples include State = California. Boolean algebra uses the conditions AND, OR, and NOT. Some examples include State = California AND City Population > 1,000,000. This will give you all the cities in California that have a population greater than 1,000,000.

3. What are the different types of spatial selection operations?
There are two types of spatial selection: adjacency and containment. Adjacency is used to identify features that "touch" other features. They can "touch" in raster when one cell is next to another one, and in vector they "touch" when two polygons share a line or a node. Containment is used to identify features that contain or surround other features. An example of this is when all the states are selected that contain a portion of the Mississippi River.

II. AFTER completing Ormsby Chapters 10 & 11, complete the following exercise.

4. Is there a feature dataset in the geodatabase?
Yes, LosAngeles is a feature dataset.

5. What features classes are present?
PtDumeQuad, Vegetation, Wetlands, and Wetland_Project are all feature classes.

III. Exercise 1: Prepare (simplify) a vegetation layer for the Los Angeles region for further spatial analysis.

6. How many features (records) exist in the Vegetation feature class in the Lab9aData.mdb geodatabase?
There are 10,896 features in the Vegetation feature class.

7. How many features (records) exist in the new VegCov feature class after running the dissolve operation?
Now there are only 9 features in the feature class.

8. How many features (records) exist in the new “VegCov_Clip” feature class?
Now there are only 8 features in the feature class.

IV. Exercise 2: Generate a layer of Riverine wetlands that fall in the Point Dume quad. 

9. How many wetland features (records) were selected?
There are 404 wetland features selected.

10. How many features (records) were selected?
There are 123 features selected.

§ Capture a screenshot (Alt PrtScr) of your final Riverine layer and paste it into this document.


Wednesday, October 27, 2010

Lab 8

I. Read Bolstad Chapter 8 and answer the following questions.

1. What are the primary functions of a database management system?
A DBMS is a computer program that organizes and manipulates data.

2. What is a one-to-one relationship between tables? A many-to-one?
In a one-to-one relationship for every record on the first table there is only one matching record on the second table.  For example, one table may include a student ID number and their name, and the other table may include the same student ID number and that students GPA. In a many-to-one relationship for every record on one table there are many matching records on the other table. For example one table may contain the different forests and the states they are located in, and the second table may contain the different trails that exist in the forests. Here the trails are the many and the forests are the one.

3. Why are relational databases so popular (i.e. what are the benefits)?
Relational databases are popular because they allow ad hoc requests. Also, if they are in normal form they can improve correctness and consistency, remove redundancy, and ease updates.

II. AFTER completing Ormsby Chapters 8 & 9, complete the following exercise.

1. You are going to join a table of landuse info to a feature class for Santa Barbara Landuse so that you can access additional information.

2. Navigate to your named folder inside the “STUDENT_DATA” folder on your C-drive. Inside of that folder, create a new folder named “Lab8”.

3. Go to the Y:\courses_rmaas\Geog206\data and copy the Lab8 folder down to your working directory.

4. Open and explore the Lab8Data geodatabase.
a. What is the Data Type of the LAND_USE field in the Landuse feature class?
String

b. What is the Data Type of the LAND_USE field in the LanduseInfo.dbf table?
String

5. Perform the following steps in ArcMap:
a. Join the LanduseInfo.dbf file TO the Landuse feature class. Explore the table. What are the new fields that have been joined (appended)? 
All of the fields from the LanduseInfo table have been join to the Landuse feature class. This includes the land use description, general, type, square miles, and acres.

b. Export the Landuse feature class to a new feature class called Landuse_all to preserve the join. (hint: make sure your 'save as type' option is set correctly.)

c. Query the new feature class to select both ‘Open Lands’ and ‘Open Land Uses’ from the LU_GENERAL field.

d. Save the selection as a new feature class and place it into YOUR Lab8Data geodatabase with the name Landuse_open.

e. How many total acres of Open Lands (including Open Land Uses) exist in this new feature class?
There is a total of 92,236.77 acres of open land

f. Open your Lab8Data geodatabase inside ArcCatalog so that all feature classes are visible. Capture a screenshot of the geodatabase contents and post with your answers.


g. Create an area qualitative map of the Landuse_all layer using the LU_GENERAL field. Include all of your map elements (north arrow, etc.) and make sure to practice your basic map design skills. In addition, create an overview inset map on your page that provides reference for the location of this county in Southern California. Use the CountyBoundary and Highways layers for your inset. Post this map to your blog.


Monday, October 11, 2010

Lab 7

Part 1: Complete Ormsby Chapters 7, 18 & 19 and answer the following questions.
I. Chapter 7
1. The information used for dynamic labels comes from where?
The information comes from the attribute table. You can control which labels are displayed by clicking the on the Labels tab in the Layer Properties dialog box. Next click on the Label Field drop-down list and select the field from the attribute table that you want to use as the labels.

2. You are making a map of Los Angeles and have a point layer that shows all the cities in the region. However, you want to show city names for only 3 cities. What is the most efficient way to achieve this?
One way to do this is to click the drop down arrow next to the New Text tool on the Draw toolbar. Then click Label tool. You can select the options that you want on the Label Tool Options dialog box, then close it. Finally click the cities that you want labels. Another way to do this is to click on the Label tab in the Properties dialog box for the layer you want to label. Check the box next to 'Label features in this layer', and change the Method to 'Define classes of features and label each class differently'. Then click the Add button, type in the new class name that you want to create, and then click OK. In the Class dropdown make sure the 'Label features in this class' box is unchecked for the Default option, and checked for the new class that you created. Next click the SQL Query button to create an expression for what you want. Type in the expression that you want to use for your query, and then click OK.

3. Can you manually adjust the position of dynamic labels?
No, you can only tell the program where to place the labels. If you want to manually move them you need to change the labels to annotations.

4. Which tool needs to be selected to adjust graphics?
The Select Elements tool on the Tools toolbar needs to be selected to adjust graphics.

5. What are the two annotation types?
Two types of annotations are geodatabase annotations and map document annotations.

II. Chapter 18
1. You can create your own ArcMap templates.
a. True
b. False
a. True

2. If you create a map based on an ArcMap template file (.mxt), can you save it as an .mxd file?
Yes, you save maps as a map document (.mxd file extension).

3. Describe two different ways you can access map templates.
One way to access map templates is when you first start ArcMap click the option to use a new template, select the template you wish to use, and then click OK. The other way to access map templates is when AcrMap is already open. Go to the File menu and click New.  In the create new section of the dialog box click template, select the template you wish to use, and then click OK.

4. You are adding five point graphics to your map. Instead of having to change the properties for each one after you add it, you want to set the default point symbol to a size 12 purple star. How do you do this?
In the TOC click on the symbol for the point graphics that you want to change. This opens the Symbol Selector dialog box. Here you can change the symbol, color, size, etc. of the point graphics. In this example you would click on the star symbol, change the size to 12 point, and change the color to purple. Once you do this click OK, and the point graphics will change to show the new properties you selected.

5. Describe two different ways you can change the color of a graphic circle.
If you right click the graphic circle and select properties, or double click, the Properties dialog box will open. Here you can change the size, color, and symbol of the graphic circle. Once you have made the changes that you want click OK and they will be applied. The other way to change the color is to first select the graphic circle. Next on the Draw toolbar click the drop-down arrow next to the line color and select the color you want to change the line to. If you also what the change the fill color click the drop next to fill color and select the color you wish to fill the circle with.

III. Chapter 19
1. What is the first thing you should always do before setting up your map layout?
The first thing you should do is setup your page size and orientation.

2. Why is the scale different in the data view versus the layout view?
The size of the data frame is different in the two different views. In data view the size of the data frame is the whole screen, but in layout view you need to adjust it so it fits on your page. In addition, you may have multiple data frames in layout view requiring even smaller data frames. Since the data frames are smaller the scale must also become smaller to accommodate this.

3. What are three customization options available for the scale bar?
There are several customizations that you can do to a scale bar. Three of these are the number of divisions and subdivisions, the division units used, and when the scale bar is resized what is adjusted (width, division values, and number of divisions).

4. Why is it important to use the 1:1(Zoom to 100%) button?
When you zoom to 100% you are able to see what the view would see when the map is printed.

5. Explain how a graphic added to your data view would respond differently compared to a graphic added to the layout view when navigating around your map.
If you add a graphic in data view it has a dynamic relationship to the map. If you pan around or resize the map the graphic is automatically adjusted to maintain its relationship with the map. If you add a graphic in layout view this relationship does not exist. The graphic will stay in the same place and keep the same size regardless to what you do to the map.

Part 2: More about Mapping in ArcGIS
Creating Thematic Maps
Q1: Choropleth maps are a type of thematic map. Define what we mean by a choropleth map.
Looking at the origin of the word choros means place and plethos means magnitude. In other words a choropleth map is used to show the magnitude of different places.

Q2: Read about layer files in the ArcGIS Desktop Help. Describe their benefits.
Display properties for labeling and symbolization are included in a layer file. However, they only reference a data source instead of including the actual datasets.

Q3: How do layer files differ from layer packages?
A layer package includes the layer file, the dataset, and an XML file. It is used to share the information with other users.

Map Tips and Dynamic Hyperlinks
Q4: What is the population of City of Long Beach for the year 2000?
461,522

Q5: What is the population for the City of Los Angeles in 2000?
3,694,820

Q6: Using the ArcGIS Desktop Help, describe the three types of hyperlinks that can be created.
Document, uniform resource locator (URL) and macro are the three types of hyperlinks that can be created. A document type of hyperlink launches a document or file when a feature is clicked with the Hyperlink tool. A URL launches a web page when a feature is clicked with the Hyperlink tool. The macro type allows you to create customized hyperlink behavior.

Monday, October 4, 2010

Lab 6

Answers are from Ormsby Chapters 5 & 6
1. In your own words, describe how symbology can be influenced by scale.
When displaying quantitative data the scale that you use to display the information can show what is going on with the data, or mislead the reader to thinking something else is going on. This is especially true if graduated colors or symbols are used. If the scale is too small (too few symbols/colors) then it may hide what is really going on, and if it is too large (too many symbols/colors) the map may become confusing and hard to read.

2. What are two ways (one direct and one indirect) to access a layers symbol colors so that they can be changed?
One direct way to change the symbol color of a layer is to right click the symbol next to the layer, or double click the symbol. This opens the color palette/symbol selector and allows you to select the color that you want. The indirect way of changing a layers symbol color is to double click the layer. This opens the properties panel for the layer. Once in the properties panel click on the "Symbology" tab. Make sure "Features" is selected in the show box. Here you can click on the color to access the color palette/symbol selector and change your symbol color to what you want.

3. How would you access the graduated symbols classification option?
To access the graduated symbols classification option first double click the layer. This opens the properties panel for the layer. Once in the properties panel click on the "Symbology" tab. Make sure "Quantities" is selected in the show box, and click on graduated symbols. Next click on the classify button. This brings up the classification dialog box, and in here you can change the type of classification.

4. What are 5 other symbology styles (in addition to ‘Conservation’) that are available to customize your features?
Hazmat, environmental, weather, real estate, and transportation are five other symbology styles.

5. How could you permanently save layer symbology for use later on?
Right click the layer with the symbols that you want to save, and click "save as layer file." Then choose where you want to save the file to and what you want to call it, and then click save.

6. How can pyramids help raster data display faster?
Pyramids are a version of raster data, and are used to help improve the drawing speed of raster layers when you zoom in and out.

7. How could you quickly and temporarily change a layer name to aid display in the Table of Contents?
In the Table of Contents select the layer that you want to rename. The click it once more (not a double click) to be able to change the name in the Table of Contents. Another way to change the name of a layer is to double click the layer. This brings up the Layers Properties dialog box. Under the General tab you can rename the layer in the Layer Name text box.

8. What is normalization? Give an example of when it would be used.
Normalization is when you find a ration between two attributes by divide one by another. Displaying population density is one example of when you would want to do this.

9. How could dot density maps be misleading?
Dot density maps can be confusing because the dots are randomly placed on the map. If a reader is not familiar with reading dot density maps they may assume that the location of the dot has meaning when it really doesn't.


Tuesday, September 28, 2010

Lab 5

I. Answer the following questions based on Bolstad Chapter 7 and lecture.

1. What are some advantages and disadvantages of using digital spatial data?
Many spatial data exist at low or no cost, it is the easiest, quickest and least expensive source of spatial information, and data is collected more frequently in digital formats to provide efficient processing are some of the advantages to using digital spatial data. Some disadvantages include the need to analyze the data before using it to make sure it is appropriate for your needs, it may not be up-to-date, and depending on the area you are looking at it may be a lower resolution.

2. What are the most important questions you must ask before using already-developed spatial data?
Does the data provide the necessary information, detail, and accuracy for the given area?

3. How do DOQs differ from regular photographs?
DOQs are georeferenced.

4. Choose three existing data sets and describe who produces them, what the source materials are and what they contain.
1) http://seamless.usgs.gov – This is provided by the USGS, and they offer national land cover data and digital elevation models.
2) http://ec2.usgs.gov/geodata/index.php - This is provided by the USGS, and they offer digital line graphs.
3) www.fws.gov/nwi - This is provided by the U.S. Fish and Wildlife Service, and provides a national wetland inventory.

5. What is the difference between DEMs and NEDs?
NEDs are a combination of DEMs for the United States. The used the highest-resolution DEMs and are combined seamlessly.

II. Step through the following instructions and answer any associated questions.

1. Launch ArcCatalog and navigate to the T drive. Copy the following GIS data down to your Lab5 folder on the C drive (or U, Z, I, etc.).

a. USGS 1:24,000 Topographic Quads: T:\\gis_data\usgs\quad_grids\topoq24.shp

b. LA County Landuse: T:\\gis_data\miscellaneous\socal_landuse_2000\Los_Angeleslu_2k\lacounty_lu01.shp

2. Go to my folder for Geog206 on the Y drive and copy the Lab5Data.mdb geodatabase down to your Lab5 folder. Explore the geodatabase.

a. What are the names of the feature datasets in the geodatabase?
Basemap and Hydrology are the two feature datasets.

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

c. For each one of the feature classes you just listed, describe whether it is a polygon, line or point layer.
NHDFlowline - line layer
NHDPoint – point layer
NHDWaterbody – polygon layer
Watersheds – polygon layer

3. Using ArcCatalog, answer the following questions.

a. Is topoq24.shp a raster or vector layer?
Vector layer

b. What is the GIS data format of topoq24.shp?
It is a shapefile.

c. Is there metadata associated with topoq24.shp?
Yes

d. What is the GIS data format of the NHDFlowline layer?
It is a geodatabase format.

e. Is there metadata associated with NHDFlowline?
Yes

f. What are 3 keywords used to describe the NHDFlowline layer?
Hydrology, Stream/River, Lake/Pond are all keywords used to describe the NHDFlowline layer.

g. Who created the NHDFlowline layer?
Earth Science Information Center, U.S. Geological Survey created this layer.

4. Export the NHDFlowline feature class to a shapefile format, name it NHDFlowline.shp and place in the Lab_5 folder on your C-drive.

a. Is there still metadata associated with the layer?
Yes

5. Open ArcMap and load the following layers. topoq24.shp, CountyBoundaries, Highways and lacounty_lu01.shp. Save the ArcMap document in your Lab5 folder and name it Lab5.mxd.

6. In the next step, you will use the topo layer to figure out which DOQQ to download from the CASIL website so that you can view the CSUN campus.

a. In ArcMap, open the attribute table for topoq24.shp.

b. In the USGS_QD_ID field, find the value that corresponds to the Canoga Park QUAD_NAME. What is it?
34118-B5

c. Click on the following link:

d. Use the first 5 digits of the USGS_QD_ID value to figure out which folder to go into.

e. Once in the folder, you want to download the canoga_park_ne DOQQ.
Note: You can sort the quad names by clicking on the Description field.
Note 2: For each DOQQ you download, you will need the .tif, .tfw AND .tif.xml files.

f. To download: Right-click on each file separately and choose Save Target As. Make sure you save to the Lab5 folder on your C-drive.
7. Load the DOQQ tiff into your Lab5 ArcMap document. Is the DOQQ black and white or CIR (color infrared)?
Black and White

8. Use the DOQQ and Highways layer to find the CSUN campus. Zoom to that location. Capture a screenshot (Alt+PrintScreen) and paste into a Word document with your other answers for this assignment.


9. Save your Lab5.mxd document and close ArcMap.

10. In ArcCatalog, navigate to your Lab5 folder. Capture a screenshot (Alt+PrintScreen) of the expanded folder/file structure and paste into a Word document.


11. In ArcCatalog, navigate to the Lab5 folder and rename lacounty_lu01.shp to La_Landuse.shp. Note: You will not be able to do this if ArcMap is still open.

12. Open the Lab5.mxd document again.

a. What happened to the lacounty_lu01.shp layer?
It now has a red exclamation mark next to it.

b. Fix the problem by redirecting the layer to the new data source name.
Right click the layer and go to properties. Under the Source tab click set data source, and redirect it to the new data source name.

13. Save the ArcMap document and exit.