AVS Modules						             string list
NOAA/ERL/Forecast Systems Laboratory


NAME

	string list - input a series of character strings

SUMMARY

	Name		string list

	Type		data input

	Inputs		none

	Outputs		string

	Parameters

	    Name		Type		Default		Min Max Choices

	    action		radio				step, auto, edit
	    string list file	browser		$NULL
	    list string		browser		$NULL
	    user string		typein		$NULL

DESCRIPTION

	String list is a coroutine module that can be used to input a series
	of strings from a list, a single string from the list, or a string from
	the user.  If a list of strings is supplied, the strings may be input
	"automatically" (read as fast as the network will accept them) or 
	stepped through one at a time.  The list may be editted by skipping
	over individual strings.  If the user-supplied string contains an
	asterisk, the string is used as a template -- each list string is
	substituted for the asterisk wildcard to create the actual string that
	is output.

INPUTS

	None

PARAMETERS

	action

	    The action parameter is used to specify the level of control over
	    the string generation that the user wants to exercise.  If "step"
	    is selected, a list of strings will be processed one at a time as
	    "step" is again selected for each string.  Strings manually selected
	    from the list or supplied by the user will be accepted only when
	    "step" is also selected again.  "Auto" causes string list to process
	    the list as fast as the network will receive the strings it outputs.
	    Strings manually selected from the list and those supplied by the
	    user will be accepted immediately.  "Edit" works in much the same
	    way as "auto" except that with each new string the user is asked
	    whether or not the string is to be used.

	string list file
	list string
	user string

	    The string list file parameter is used to specifiy the name of the
	    file that is the list of strings to be processed.  When a string
	    list file is specified, the file is read and its list appears in
	    the list string browser.  This allows one or more entries to be
	    manually selected from the list.  If no string list file name is
	    specified, no list strings appear and strings can only come through
	    the user string parameter.  Strings may be individually specified
	    through the user string parameter.  A user string takes precedence
	    over a list string, unless the user string contains an asterisk
	    ("*").  In this case, the user string is treated as a template and
	    the asterisk is a wildcard at whose place the list strings are
	    substituted.  To create a template that is a file path, the user
	    string widget can be changed to a browser with the module editor.

OUTPUTS

	Output String

	    The output of string list is one or more character strings.  These
	    strings may then be used by other modules in a network for file
	    names, etc.

EXAMPLE

	This example creates a pixmap animation sequence of isosurfaces made
	from a series of fields.  String list is used to create the field file
	names and the animation is performed by display pixmap.

		           STRING LIST
		                |
		           READ FIELD
		                |
		           ISOSURFACE
		                |
                         RENDER GEOMETRY
                                |
                          DISPLAY PIXMAP

LIMITATIONS

	When the "auto" option is selected, an effort is made to ensure that
	string list synchronizes with the network so that it doesn't cough up
	the next string until the network is ready for it.  This works most of
	the time, but it may not work all of time.

AUTHOR

	Phil McDonald, NOAA/ERL/Forecast Systems Laboratory


NOAA/ERL/Forecast Systems Laboratory
AVS Modules						             string list