1. Setup Everyone: Mount the /geobase/geo5215 drive and add a new Lab4 folder in you Labs directory.

Transcription

1 L A B 4 E X C E L For this lab, you will practice importing datasets into an Excel worksheet using different types of formatting. First, you will import data that is nicely organized at the source. Then you will import data that needs some work at the import stage ( comma delimited ). You will also practice formatting your data, plotting it, and performing some simple calculations on it, which in turn will allow you to add new information to your table. 1. Setup Everyone: Mount the /geobase/geo5215 drive and add a new Lab4 folder in you Labs directory. PC users: Familiarize yourself with where your computer keeps Microsoft Excel and NotePad (Programs Accessories Notepad). Mac users: In your Applications folder, drag both the TextEdit and Microsoft Office Excel icons to your dock. You will be using both of these for this lab. 2. Collecting data: Global Earthquakes In a web browser, navigate to the USGS earthquake website: - Along the left column menu, click on Search EQ Database. - Then click on Rectangular Area for your Search Area. - Select Screen File Format (80 columns) as your Output File Type;. - Under Data Base, select the USGS/NEIC (PDE) 1973-Present Data Base. - Enter the following coordinates under Input Rectangular Area Search Parameters: 3 (bottom latitude), 5 (top latitude), 96 (right longitude) 91 (left longitude); - Under Optional Search Parameters, enter the date range of 01/01/1980 to 01/01/2008 and enter as your minimum and maximum magnitudes. Leave the rest of the boxes blank. - Click the Submit Search button. 1

2 Your data should appear on the next screen. Select and copy all of the column data. Then paste the data into a simple text editor: PCs: Use the Notepad application. Notepad will save as a *.txt file. Macs: Use the TextEdit application. When you save the file, select the Rich Text Format (RTF). Save the file (give it a good name) to your Lab4 folder. You have now saved your data as a text file. Leave the webpage open so that you can later compare your Excel dataset with the one you just copied. 3. Importing nice (formatted) data Open Excel and a new blank spreadsheet should appear. To open the new file you just created, click on File Open. In your Open window, change the file type option to all files/documents : PCs: Files of type select All Files (*.*) select your text file Open Macs: Office 2008: File Import Text File Import Enable: All Files select your text file Get Data or Office 2004: Enable select All (Readable) Documents select your text file Open 2

3 You will next be greeted by the Text Import Wizard screen. Follow the instructions on the wizard s screen to import your data in the Excel format. Inspect all of the options presented to you in each Step of the Wizard, making sure you understand how each operates. You may see some garbage text in the Preview panel of the screen this is okay for now, and you ll get rid of it later, however scroll down to check that the rest of you data is in column format. When you encounter the select field breaks (column width) window (Step 2), create breaks at every obvious column, however group the date (year/month/day) columns into one break, and select the appropriate format for the date (Step 3). You can also skip importing the last few columns on the right that appear useless (symbols, etc.) After completion of the Wizard steps, you should have a series of columns with nicely organized data. If you have any garbage text remaining in your worksheet, simply remove it by highlighting the text and then go to Edit Clear All. 4. Saving the file File Save As On the Save As screen, look for the Save as type or Format option and select MS Excel Workbook or Excel Workbook (v ). The default suffix should be (*.xls or *.xlsx). Give your file a name and click Save. 5. Importing not-so-nice (formatted) data Now return to the USGS Earthquake website (hit your back button from the data screen) and import events from the same location, but now with a magnitude range of Also change the output type to Spreadsheet Format (comma delimited). Try to import your data in the same manner as you did for the previous exercise, entering the new data into a new worksheet. Save this new file as you did in the above section. Note: you ll probably have to try a few different ways of importing this data set, paying particular attention to date format.. 6. Clean up 3

4 Clean up both of your data tables by first rearranging your columns (copy/paste) so that they appear in the following order: Date (year/mo/day) Latitude Longitude Magnitude Depth Delete the UTM (UTC) column entirely, and any other remaining columns. Also give title labels to each of your columns (with proper units!). If you forget what each column represents, refer back to the USGS website. Make sure that the format of each cell is correct. If the data needs formatting, select the necessary cells and use Format Cells (specifiy fixes here). (Shortcut: highlight the data you want to format and right-click on your mouse Format Cells). If the cells are not properly formatted, you may loose decimal places, or your values may not display as expected. Also add borders (of your choice) to your table. Align all text, except title labels, to the right side in each column. Also add your name and the date to the worksheet. DON T FORGET TO SAVE! 4

5 7. Plotting the data Using the earthquake data that you collected, you will now practice a few simple Excel plotting techniques. As a trial run, first generate an x-y scatter plot of earthquake magnitudes vs. depths for your magnitude data set. - Using your mouse, highlight the data you want to plot (depths and magnitudes columns). - Select Insert from the menu bar, then select Chart from the pull down menu. If you re running Office 2003/04, a Chart Wizard Popup window to create a plot. The 2008 Office version does not have a Wizard. - Click on XY (Scatter), then click on the graph type labeled Scatter or Marked Scatter (the one without the lines). - PCs: follow the Wizard steps to edit the contents of the chart. - Macs: Use the Formatting Pallet to edit the contents of the chart. - Give your plot a title and also fill in names for the (x) horizontal axis and the (y) vertical axis. - Try moving/saving your entire chart to a new file. Now, try formatting with the chart/graph. In most cases, you can change some aspect of the graph by double-clicking on that part. You can also use the right-click shortcut on your chart, or use the chart Formatting Pallet (Macs). Try to do the following: - Get rid of the little legend box on the right. - Stretch the graph to fill the whole window. - Change the color of your data. - Change the color of the background. 8. Using Formulas One of the most powerful tools of Excel is formula editing. To practice using Excel s formula function, you will make two new columns in your table, where you will calculate normalized magnitudes and normalized depths. For this exercise, you will need to calculate the mean magnitudes and the mean depths of all of your earthquakes, and divide your respective magnitudes and depths by these means values. - Click on the cell below the last entry of your magnitude column (this is where you will have your mean depth entered). To calculate the mean (or average) magnitudes, select Insert Function Select AVERAGE. Click Okay. Then enter the cell numbers of the 5

6 magnitude column, for example D10:D20 would calculate the average of the cells defined by the range D10 through D20. - Click Okay. Repeat for the depth data. - Now you will make a new column to the right of you data table. Click on the first row of your new column, enter = and click on the first row in your magnitude column. Back in the cell you just typed in, type /, click on the AVERAGE value that you previously calculated, and finally enter a $ between the letter and number designation for the AVERAGE cell. - To fill the rest of the column, align your hand cursor with the bottom right corner of the cell you just filled, and wait until the hand turns into a cross. Click and drag your cross cursor down to the extent of your data table, then release. The rest of your new column should automatically fill. Hit enter/return. - Repeat this step to calculate normalized depths. 9. Sorting Data Just like you practiced in UNIX, Excel will also sort data. - Highlight the data you want to sort, then select Data Sort. - Follow the Sort menu options to list your data according to the date. 10. Done. - Save your completed document as a PDF file. PCs: If your computer has Adobe Distiller installed (some do): Print Printer Name box, select Adobe Distiller Okay nameoffile.pdf If no Adobe Distiller option is listed, I d opt for getting on a Mac to make the PDF. Macs: Print PDF button Save as PDF nameoffile.pdf. - Copy your file to your Web/Computer_Class folder on /geobase/geo5215, add a link to it on your index.html file in your Computer_Class directory, and ftp these over to to post on the web. 6