FileMaker Pro Custom Functions

Can you find it.I hop you cn find it in a good.

william royster, ohio
March 26, 2009 7:45am

Just one little addition to the leap year factor that might be easily forgotten...
The year 2000 is not a leap year, because it's divisible by 400.

Let ( leapFactor = If ( Mod ( Year ( theDate ) ; 4 ) = 0 AND Mod ( Year ( theDate ) ; 400 ) ≠ 0 ; 1 ; 0 );

Alexis Gehrt, Laax / Switzerland
November 30, 2009 8:35am

Sorry, Alexis, but check your calendar again. 2000 WAS a leap year, because it's divisible by 400. The 'century' years are normally not leap years (1800, 1900), except when divisible by 400. So the calc for leapFactor should really be:

leapFactor = Case ( Mod ( Year ( theDate ) ; 400 ) = 0 ; 1 ;
// 'century' years divisible by 400 are leap years
Mod ( Year ( theDate ) ; 100 ) = 0 ; 0 ;
// 'century' years not divisible by 400 are not leap years
Mod ( Year ( theDate ) ; 4 ) = 0 ; 1 ;
// years divisible by 4 are leap years
0 )

Rob Woof, Sydney/Australia
August 08, 2010 7:13pm

There's another way that bypasses the Case statement.

leapFactor = If ( Mod ( Year ( theDate ) ; 400 ) = 0 ; 1 ; 0 ) // 'century' years divisible by 400 are leap years
- If ( Mod ( Year ( theDate ) ; 100 ) = 0 ; 1 ; 0 ) // 'century' years not divisible by 400 are not leap years
+ If ( Mod ( Year ( theDate ) ; 4 ) = 0 ; 1 ; 0 ) // years divisible by 4 are leap years

A year that is divisible by 400 (e.g. 1600, 2000) will evaluate to 1 - 1 + 1 = 1.
A year that is divisible by 100 but not by 400 (e.g. 1300, 1900) will evaluate to 1 - 1 + 0 = 0.
A year that is divisible by 4 but not by 100 (e.g. 1972, 1988) will evaluate to 1 - 0 + 0 = 1.
Any other year (i.e. not a leap year) will evaluate to 0 - 0 + 0 = 0.

Just another way to skin this particular cat.

Rob Woof, Sydney/Australia
August 11, 2010 8:48pm