3.1 Plotting a Satellite Image File

To plot a satellite swath file, select File with the left mouse button in the control area. A small window will appear with its upper left corner at the cursor (see Fig. 2). This new window (Data File Name) will permit you to specify the name of the file you wish to plot. It also allows you to browse through your directories until you find the file that you want.

Figure 2: The Data File Name Window

At the top are three buttons labelled OK, Cancel, and Rescan. When you click the OK button, SatView will plot (or perform the appropriate action on) the file whose name is in the file text field. If you change your mind about loading a file, click Cancel, and the operation will be aborted. Click Rescan to update the list in case files have been added to or deleted from the current directory.

Below the buttons, there is the text field labeled File. It is waiting for you to type in a filename, a directory name, or a pattern. To activate, hit return.

Below the File text field is a scrolling list. The label immediately above the scrolling list displays the current directory and the current pattern. The scrolling list itself contains all files in the current directory that match the pattern. For instance, if the label is/u/users/jones/*.c, the scrolling list contains all files in directory/u/users/jones that have a `.c' extension. Clicking the left mouse button on any filename in the list will display that filename in the File: text field at the top of the window. To scroll the list, move the scrollbar slider up or down with the mouse.

A shorthand way to select and load a file in the list is to double-click on the file name. Double clicking on a directory name moves to that directory. The item at the bottom of the window labeled Include All Directories provides the option of including all subdirectories of the current directory in the list, regardless of whether they match a pattern.

Example 1.

If the file you want to plot is in the current directory:

  1. Scroll the list until your file name is visible. Click on it.
  2. Click OK.

Example 2.

If you want to browse a different directory for the file:

  1. Click the left mouse button in the empty field to the right of the word File at the top of the window.
  2. Type in the path name (relative or absolute) of the directory you want to change to and hit return.
  3. See Example 1.

Here are some things you'll want to try:

  1. What happens if you click on a directory name in the scrolling list?
  2. What happens if you type in a nonexistent file or directory name?
  3. What happens if you type in a wildcard expression like file[1-3]*.o?

Large satellite files can take a long time to draw, especially at full resolution. Sometimes, a user may decide he doesn't want to wait for the drawing to finish. To interrupt plotting of a file, choose Stop Plotting from the File menu. This form of interruption is only possible if the Time Slicing option (found in the Properties window) is enabled.