Subtract Dates from each other

Questions and Help
1

Hi,

Not sure if this has been brought up before, but looking to create a snippet where I am able to subtract days from each other. I found this topic but it's not quiet what I'm looking for. (Subtracting months)

Here is the full idea for reference:
My team calculates how much to spend per day on Ad Campaigns. They usually apply a formula: Budget / (End Date - Start Date)

The idea would be to use 2 Form Inputs, enter the days, and then receive the difference in number of days. Then also have a Form Input to enter the budget, and return out the Spend Per Day. However, I am struggling to get the dates to subtract from each other.

2 Likes
2

Hi, and welcome to the forum! :slight_smile:

You can do this using the "X" format option for the {time} command. It converts the time/date to a timestamp which is the number of seconds since 1970 (this is a standard unit of time for computer systems). You can then use that to calculate the time between two dates.

For example:

Budget: ${formtext: name=budget; default=10000}
Start Date: {formtext: name=start; default=2020-01-01} (YYYY-MM-DD format)
End Date: {formtext: name=end; default=2020-01-31}

{days=({time: X; at={=end}} - {time: X; at={=start}}) / 24 / 60 / 60} (calculate difference in seconds and then convert to days)

Per day rate {=budget / days; format=$,.2f}

As an aside, we're planning on launching a date selector in the coming months that will make entering a date simpler. You can take an early look at it here:

3 Likes
3

This is so cool! Thank you so much! Super helpful! I see the part of my snippet that I was struggling with so thank you. Going to be a huge improvement to productivity!

1 Like
4

Quick update to this popular old thread. This use case is now much easier to do, like in the example below:

Start Date: {formdate: YYYY-MM-DD; name=start}
End Date: {formdate: YYYY-MM-DD; name=end}
{days=datetimediff(start, end, "D");trim=right}
Difference is {=days} days

I have used the datetimediff function and formdate command.

1 Like
5

(({formdate: MM/DD/YYYY; start=2024-01-01; end=2036-12-20; name=TODAY})) POST-OP VISIT today.
..... DATE OF SURGERY: {formdate: MM/DD/YYYY; start=2024-01-01; end=2036-12-20; name=SURGERY}
{days=datetimediff(TODAY, SURGERY, "D"); trim=right}

SIMILAR to the above thread but trying to use the formdate for date entry and calculation. and ideas? Just want to subtract the two dates and yield the number of days between them.
{days=datetimediff(TODAY, SURGERY, "D"); trim=right} my output snippet unerrored
Thanks

update: figured the problem out. you can't use the MM/DD/YYYY date format. The original and what works is the YYYY-DD-MM format of date.

6

Hi @Brian_Haley
If you want to use the MM/DD/YYYY format, you can convert it using the datetimeparse command:

(({formdate: MM/DD/YYYY; start=2024-01-01; end=2036-12-20; name=TODAY})) POST-OP VISIT today.
..... DATE OF SURGERY: {formdate: MM/DD/YYYY; start=2024-01-01; end=2036-12-20; name=SURGERY}
{days=datetimediff(datetimeparse(TODAY,"MM/DD/YYYY"), datetimeparse(SURGERY,"MM/DD/YYYY"), "D"); trim=right}
{=days}

7

perfect!