DayName
Purpose 
Returns a text string that is the full name of the weekday for date.
Format 
DayName(date)
Parameters 
date - any calendar date
Data type returned 
text
Examples 
DayName(Date(10;5;2010)) returns Tuesday.
DayName(ProjectDue) returns Tuesday when ProjectDue is 10/5/2010.
DayName(“10/5/2010”) returns Tuesday.
“Return your selection by ” & DayName(DueDate) displays the text Return your selection by followed by the name of the day stored in DueDate.
Important  To avoid errors when using dates, always use four-digit years. For more information about how FileMaker Pro handles two-digit dates, see Conversion of dates with two-digit years.
Related topics 
Functions reference (category list)
Functions reference (alphabetical list)
About formulas
About functions
Defining calculation fields
Using operators in formulas