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2.5. Projects

A project is a collectiion of satellite images, maps, etc. and the parameters used to display them. It allows you to assemble under the same menu various information about a given subject.

The parameters used to display this information are organized into an ASCII text file and accessed through a dialog box located on the left side of the main window. You can see in the example at the left the various kinds of information that can be included in a project: images, maps and statistics. From the project dialog box, you can check off the layers that you wish to see, and display them in the active window or in a new window.

In this example, the user chose to display a dekad (ten day) satellite image using predefined variables (described in a later section), and superimpose national boundaries and the rivers of the country. The result obtained by clicking on the Draw button is shown below.

 

2.5.1. Creating a project

To create a new project, use the command File New Project from the menu. You will be able to select layers from the menu and put them in a file. To add a layer from the Draw menu, you will have to furnish the coordinates using the dialog box.

You will be asked to give a key-word, or descriptor, to identify each layer you add to the project file. A check box will appear in the project window with the new descriptor and a box to select the next layer. If the active window is the display window, the new layer will be drawn. Otherwise you can select the layer and click the Draw command to see the new layer. Values and descriptors can be deleted from the list by selecting them and pressing the Delete key. You must then confirm if you want to delete that item from the list.

After all the desired layers have been added, save the project using File Save Project. The contents of the project will be saved in the form of an ASCII text file.

2.5.2. Using variables

When adding or editing a project layer, you may want to allow the selection of a parameter, or part of parameter, from a list of possible choices. To do this you can include a variable in the parameter. The name of the variable must be delimited by % signs before and after. For example, the user can specify the precise date of the image desired with the command:
c:\images\%Type_image%\%Type_image%d%year%%month%%dekad%.af

When you select a layer that contains variables, a dialog box appears. This window contains a scroll list permitting you to select the descriptor for each variable.

The window at the left shows a layer of the project 'Satellite Image Dekad' illustrated on the previous page. The values chosen for the variable are displayed in the spaces just below the descriptor of the layer.

In the project file (in ASCII text format) the command line written above, contains all the variables to start a project. In the section [Variables] is the list of values for each variable and its corresponding descriptor.

In the example reproduced in section 2.5.7, on the next page, `Cultivation' is a variable, `Fonio' is a descriptor, and `011' is a value. If a variable is written several times in a chain of parameters, it will appear only once in the selection window.

2.5.3. Displaying a project

After a project has been created and saved, it can be opened with the File Open Project command. Select the layers to be displayed by clicking on the descriptor for each layer. A check mark will appear to the left of the descriptors chosen. If a parameter of a layer contains a variable, a dialog box appears in which you enter the values for the variable.

When all the desired layers have been selected, click on the Draw button. If several windows are open at the time, you can select the display window in several ways:

- you can click on the desired window before selecting the layers, and then display the layers in this active window

2.5.4. Editing a project

Projects can be edited in two ways. A knowledgeable user can open a project as an ASCII text file with the Windows Notepad or with File Open Text within WinDisp3.5, and make changes in the ASCII text file.

An open project can be edited directly. To change the parameters in a layer, double-click on the layer graphic in the project box. The dialog box of that layer will appear, and you can make the necessary changes there. To delete a layer, simply click on that layer and press the Delete key. To add a layer, open the project window and perform the desired functions from the menu or the button bar. Do not forget to save the project if you make changes.

2.5.5. Saving a project

When a project has been created, it can be saved with the File Save Project menu option. You will be asked to supply a name for the file, preferably with a (.prj) extension.

The layer descriptors, functions and parameters will be saved in the Parameters section of the ASCII text file. The variables, descriptors and values will be stored in the Variables section, and the types of information and the variables chosen for each layer in each window will be stored in the Settings section.

2.5.6. Sample project

The execution of a project is based on the storage of menu commands necessary to open a database and run the program when a user chooses to display the information. In the project there is a line, or a group of lines if there are variables, with the available information structured exactly in the same way as if the commands were executed manually.


"Parameters" are separated by commas, in the order in which they appear in the corresponding dialog box. In order to write a title on the display, use the following line of commands:

Note in the following example, the variables are delimited by % signs; this gives the user access to the file where the desired information can be found. The variables are replaced automatically by the values selected. When a variable (example %type%) appears several times in a file it is replaced successively by the different indicated values in the project following the selected descriptor.

To illustrate this, the example presented at the beginning of this chapter will be used to view the dekad satellite image for the duration of cold cloud summits (CCD - Cold Cloud Duration) during the third dekad of July 1997. The part of the project used to find the file you want is the following:

2.5.7. Sample project file

A project file as described above follows:

The [Parameters] section is the 'body' of the project, and is always required. The [Variables] section is required when a minimum of one variable is present in the [Parameters] section, and the [Settings] section is optional.


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This manual was prepared by the Global Information and Early Warning System of the United Nations Food and Agriculture Organization
© FAO/GIEWS - 1999
E-mail: Giews1@fao.org