Na Lu HOME

Homework 1

In this homework, I did the Excise 3.a-3.d in Getting to know ArcGIS . These exercises mainly teach you how to display map data, navigate a map, use basic tools and look at feature attributes.
Exercise 3a step 17	This map shows the World Population Layer. The darker the color of orange, the higher the population of a country. The two countries with darkest color are China and India. We can identify them by using the Identify tool. When we open several layers simultaneously, it is important to place the layers in the order that points and lines on top of polygons so that you can see all the layers at a time.
Exercise 3a step 18	This map shows the Air Pollution by Country Layer. Color red represents countries with worst air quality, followed by orange, yellow and green. Compared to the map above, we can see some countries with high population are also have higher air pollution level, like China and India. However, some African countries with low population also suffer high air pollution level. While countries like USA, though with relatively high population, has very clean air. So it is not necessary that high population always correlate with high population.
Exercise 3b step 8	This exercise talks about zoom in/out, pan and previous/ next extent. For some small countries, we have to zoom in to see it more clearly. This map shows the Middle East area with a lot of small countries. We can hardly tell them or use MapTip in the original scale. But now, after zooming in and using Pan tool, we can see a map with clearer view of this countries.
Exercise 3b step 9	We are able to see the country information by clicking Identify Tool and click the country of interest. For example, the map on the left has the identify window for Iran. It shows the ISO numbers and so on.
Exercise 3c step 12	I learned how to turn on the feature labels only at a specified map scale and see the viewer windows simultaneously. We can change the settings of Display and Labels in the Layer Properties. By clicking the Scale Range button, I can make the labels only shown when zoomed to certain scale. By using the Create Viewer Window tool, we can create another view window with different scale. When magnifier is selected, the viewer window will show the same area as the main map at the bottom.
Exercise 3c step 19	If we want to search a city we are not familiar with, we can use the Find tool. The map on the left is shown after we type Shanghai in the Find tool and select zoom to. In order to simplify the distance measure process, this exercise teaches us how to use the bookmark. For example, I created bookmark from the bookmark menu bar and name it Shanghai. After that, when I dragged the map to New York, I used the measure tool to measure the distance in two cities. I only need to click New York and click bookmark-Shanghai and the map will show the map of Shanghai. After double clicking the Shanghai in the map, the measure showed up.
Exercise 3d step 15	This exercise is all about attribute table. The attribute table can be adjusted easily and you can also hide a column by dragging. By clicking the tab to the left of a row, we can select a record which also highlights in the map. For example, I would like to see cities with population above 10 million. First, we sorted the population from high to low. Then, we selected all the rows with population higher than 10 million. These 12 cities highlighted in the map. By clicking the Show selected records button, the attribute only contains the records we selected.
Exercise 3d step 16	Simple statistics can be seen by right clicking the filed name and statistics. The table on the left shows some basic statistics of the 12 cities population I selected.