Date calculations

Sarah sarahr at genesearch.com.au
Tue Jul 15 17:44:01 EDT 2003


Hi Ubaldo,

The easiest way is to convert your dates to "the seconds" i.e. the 
number of seconds since 1/1/1970. This way they are a single number 
that can be used in all your calculations. The only tricky bit is to 
make sure that your dates are in the format that is expected: m/d/y or 
d/m/y

Try this script but check that it is giving sensible answers before 
telling people when their baby is due :-)

on mouseUp
   ask "Enter the LMP date in m/d/y format:"  -- this is Rev's standard 
format
   put it into LMP
   if LMP is empty then exit mouseUp   -- user clicked Cancel or didn't 
enter anything
   if LMP is not a date then exit mouseUp   -- best to give an error 
message here
   convert LMP from short date to seconds
   put LMP + (60 * 60 * 24 * 280) into EDD   -- add 280 days in seconds
   convert EDD to short date
   answer "EDD (m/d/y): " & EDD
end mouseUp

You might also be interested in the Calendar stack that is available on 
my web page. It allows you to select a date graphically, rather than by 
typing and so eliminates any errors in date format. You can also return 
the result in the localised format by saying "convert EDD to short 
system date".

Cheers,
Sarah
sarahr at genesearch.com.au
http://www.troz.net/Rev/

On Wednesday, July 16, 2003, at 08:14  am, Dottor Zivago wrote:

> Dear friends,
> Sorry for another basic question to the list but:
> I would like to have a field as a container for a date, then a button 
> that
> performs a calculation on that date and puts the result in another 
> field.
> For instance, for a given LMP (last menstrual period) I need to 
> calculate an
> EDD (estimated date of delivery) that is simply LMP+280 (and this is 
> what I
> do in Excel or FileMaker).
> Pleeeease, assume an IQ<=40; some lines to cut and paste between "on
> mouseup" and "end mouseup" would be very very appreciated.
> Thank you very much
> Ciao
> Ubaldo





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