FKey Menu Basics

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10.3.0 FKey Menu Basics

The F Key menu allows you to access data and execute McIDAS commands by pressing function keys on your keyboard. The F Key menu template assigns function keys to specific actions. How this is used in the Unidata Fkey menu is explained in more detail in the next lesson). Fkey menu creation is discussed in F Key Menu System of the Unidata McIDAS-X User's Guide.

A screenshot of the McIDAS-X F Key menus is shown below:

McIDAS-X:

Function Key Assignments

F1

F12

Alt

Ctrl

Shift

Screen Listing	Meaning

F1 - F12	simple function key selections
SF1 - SF12	<Shift> + function key selections
AF1 - AF12	<Alt> + function key selections
CF1 - CF12	<Ctrl> + function key selections

Function keys can access submenus, or run McIDAS commands. In the example menus above, you can access the Latest Images/Image Loops submenu by pressing the F1 key on your keyboard. To access Surface Data Plots, you would press and hold down the Shift key and then press the F1 key.

In most menu screens in the Unidata F Key menu system, the F12 key will return you to the previous menu. Pressing the escape (Esc) key will return you to the Main Menu.

Unidata Menu Concepts

Background Maps

In the Unidata F Key menu system, there is a concept of a "default background map". The default background map is the map on which all horizontal gridded data sets are plotted. You can also select the default background map from the various "regions" menus. This concept is useful if there is a particular map that you want to use most often when plotting or contouring. When you install your McIDAS distribution, the default background map is set to be a US CONFormal map. You can change the default background map at any time or reset it back to the default using the Menu Administration menu.

The default background map definition is saved in the string ?BKGMAP in the string table. The map outline is also saved in the VIRTual graphic file VIRT9300. When you run a plot or contour out of the menu and select the default background map, the McIDAS commands use the string definition to create the plot and the VIRTual graphic file is restored to the frame.

The map definitions for the default background map are created using the BATCH file BKGMAP.BAT. You can add your own map definitions to this file if you want to (more on this later).

Default background maps are not limited to simple geographic maps. There is a set of TOPOgraphic area files that are distributed with McIDAS that can be used as background maps as well.

Output Frames, Overlays and String Table Manipulation

For each type of data output (surface, upper air, imagery) there is a default output frame assigned using strings in the string table. The default frame assignments are provided in the UNIMENU.DEF file. You can change the output frame assingments through the Modify Menu System Parameters submenu in the Menu Administration menu. You can also restore the default frame assignment strings through the Menu Administration menu.

There are other strings that you can manipulate to customize your plots through the Modify Menu System Parameters submenu. For example, you can control whether or not a data bar is displayed on images and whether it is displayed vertically or horizontally ( ?BAR string). You can change the interval over which lightning data is plotted (?NLDNINT). Examples of screens for Modifying the Menu System Parameters are shown below:

McIDAS-X:

Additional strings are created when some commands are executed. Since there is a limit of 256 strings that can be defined in a string table, it is possible that the limit may be reached. At that point, you will see errors in the text and command window that the string table is full. You can remove excess strings from the string table using the option in the Menu Administration menu. This will clear out strings created by the menu system commands that have special prefixes, but will not delete any user defined strings that start with letters or numbers.

System Key Table and Use of Pseudo-Strings

The Unidata F Key menu relies on access to various bits of information in the System Key Table, SYSKEY.TAB. Many commands executed from the menu use the #SYS(n) pseudo-strings when determining what data to plot.

Prompts for input

In some instances, input is required from the user to determine the command to be run from the F Key Menu. In these cases, one of the scripting facilities is used to gather input from the user. In McIDAS-X, Tcl/Tk scripts are used to prompt for input in separate X Window screens. Examples of a screens prompting the user for input are shown above in the section on Output Frames, Overlays and String Table Manipulation.

Starting and Exiting the F Key Menu

McIDAS-X:

Users of McIDAS-X can invoke a Menu Template at any time using the MCMENU command. Users can also set up their McIDAS resource file (.mcidasrc) to invoke a menu automatically when McIDAS is started. To work correctly using the defaults assingned in UNIMENU.DEF, a McIDAS-X session is assumed to start with a minimum of 16 image frames. To start the Unidata F Key menu from the McIDAS-X command line:

Type: MCMENU UNIDATA.MNU

If you wished to use a different menu template, you would replace UNIDATA.MNU with the name of the template.

If you wish to have the Unidata (or any other) F Key menu start automatically when McIDAS starts, you could add the following line to the .mcidasrc file in your home directory:

-c 'MCMENU UNIDATA.MNU'

When McIDAS starts up, the menu template you specify will also be started in a menu window.

To exit the Unidata F Key Menu window, press F12 from the Main Menu. If you make changes to the menu template, they will not be visible until you exit menu window and restart it with the MCMENU command.

You would need to make sure that there are no conflicts between menu number assignments. See the next section for information on creating menu templates.