Date Calculation

[dena_5624]

I have looked at dozens of posts on calculating dates and have not been able to find one that fits my scenario.  I have a date field (EDD)  that I want to use to populate another date field (ECD) 280 days prior. I would also like to be able to calculate (GA) into weeks and days.  I have uploaded a pdf of what I have done in excel  but I need to be able to do this in Adobe.  I do have DC Pro.  Please help, I am still in the learning stages of javascript.

[PDF Automation Station]

Enter the following custom calculation script in the ECD field:

var EDD=this.getField("EDD").value;
if(!EDD)
{event.value=""}
else
{
var date=util.scand("mm/dd/yyyy", EDD);
date.setDate(date.getDate()-280);
event.value=util.printd("mm/dd/yyyy",date);
}

What is GA?  Weeks and days of what?

[dena_5624]

GA is gestational Age based off today date and the EDD.  Is it possible in pdf?

[PDF Automation Station]

The difference between EDD and today's date in weeks and days?

[PDF Automation Station]

var ECD=this.getField("ECD").value;
if(!ECD)
{event.value=""}
else
{
var today=new Date().getTime();
var start=util.scand("mm/dd/yyyy", ECD).getTime();
var days=Math.floor((today-start)/1000/60/60/24);
var weeks=Math.floor(days/7);
var days=days%7;
event.value=weeks +" weeks, "+days+" days";
}

This is dynamic, changing with the current date.  If you want it static based on the today's date field change

var today=new Date().getTime(); to

var today=util.scand("mm/dd/yyyy", this.getField("TodaysDate").value).getTime();

[dena_5624]

Thank you, you are a true blessing.  This works perfect. 

[dena_5624]

How could I change the script to reflect years, months, & days?

[PDF Automation Station]

Are you assuming all months are 30 days?

[dena_5624]

Would it be possible to be more accurate?  If not, 30 would be fine (it would be a close estimate).

[PDF Automation Station]

I used 365/12 for the number of days in a month.  Still not completely accurate due to different numbers of days per month, leap years, etc. but pretty close:

var ECD=this.getField("ECD").value;
var tdy=this.getField("TodaysDate").value;
if(!ECD || !tdy)
{event.value=""}
else
{
var today=util.scand("mm/dd/yyyy", tdy).getTime();
var start=util.scand("mm/dd/yyyy", ECD).getTime();
var totaldays=Math.floor((today-start)/1000/60/60/24);
var years=Math.floor(totaldays/365);
var daysLeft=totaldays-365*years;
var months=Math.floor(daysLeft/30.417);
var days=Math.round(daysLeft-months*30.417);
event.value=years+" years, "+months+" months, "+days+" days";
}

[dena_5624]

Thank you for taking the time for creating this.  It also worked perfect.  

[dena_5624]

And thank you so much it worked beautifully.