                                BIN HOURS
		
Time binning of observational data has been added to NMAP.  The data types 
that are available for time binning are: surface (SFC), surface-forecast (SFF),
upper air observations (SND) or upper air forecast (SNF).  For all other 
data types, the time binning button is insensitive to any action on it.


The datatype table $GEMPAK/tables/config/datatype.tbl contains the BIN HOURS 
in the right most column. The entry is given as, T/B/A, where:
                        T - time binning 'ON' or 'OFF'
                        B - hours before current time
                        A - hours after current time
the left most entry for BIN HOURS is whether time binning is on or off by 
default.  The next number represents the number of hours 'before' the current 
time to include in the binning.  The right number represents the number of 
hours 'after' the current time to use in the binning. Both the before and after
bin hours are positive numbers.


The 'Data Selection Window' in NMAP has a new button 'Bin Source' and a check 
box to the left of this button.  If a data type is one of the four listed 
above, the check box is active even though the 'Bin Source' button is 
insensitive. When the check box is checked, the 'Bin Source' button is made 
sensitive.  Selecting this button pops up a new GUI, 'Source Bin' and the 
user may change the number of hours before the current time to display on a 
single frame (Hours Before) and the number of hours after the current time 
(provided data is available) to display on the current frame (Hours After). 
The default setting for the text values are retrieved from the datatype.tbl 
and the time before and time after values are displayed in their respective 
text boxes in the GUI. The user may then edit the hours displayed in the text 
boxes.  There are also 4 buttons at the bottom of this GUI. Their actions are:

    a) If there are no changes to the text boxes:
        i. 'Accept' - The current values in the before and after values are 
            not changed
       ii. 'Default' - The default values for Hours Before and Hours After are 
            read  from the datatype.tbl. 
      iii. 'Cancel' -  The Hours Before and Hours After values from when the 
            pop up first came up are used. Any changes made are ignored. 
       iv. 'Help' - The help file for Bin Source is brought up.

    b) If there are changes to the text boxes:
        i. 'Accept' - The new before and after values are used.
       ii. 'Default' - The default values for Hours Before and Hours After are
            read from the datatype.tbl. 
      iii. 'Cancel' - The previous before and after values are restored. 
       iv. 'Help' - The help file for Bin Source is brought up.


Finally, the values for the time binning on/off flag, hours to bin before and 
after the current time may be saved to an SP file.  The new SPF data 
attribute line looks like: '<loop1_source1_timbin>	T/B/A', 

where:
     T - time binning 'ON' or 'OFF'
     B - hours before current time
     A - hours after current time

