# Subtract time to date

**URL:** <https://forum.inductiveautomation.com/t/subtract-time-to-date/11384>\
**Category:** Ignition\
**Created:** [March 18, 2016, 11:31am UTC](https://forum.inductiveautomation.com/t/subtract-time-to-date/11384 "2016-03-18T11:31:17Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![flavien](https://avatars.discourse-cdn.com/v4/letter/f/f475e1/32.png) [@flavien](https://forum.inductiveautomation.com/u/flavien)\
**Post date:** [March 18, 2016, 11:31am UTC](https://forum.inductiveautomation.com/t/subtract-time-to-date/11384/1 "2016-03-18T11:31:17Z")

</div>

Hi,

I wrote this python script :

```auto
from java.util import Date
now=Date()
now=system.db.dateFormat(now, "yyyy-MM-dd H:mm:ss")
yesterday='now - 1 day'
```

I would like to calculate variable “yesterday”. I tried a lot of method but it’s not working.

Can you help me please ?

---

<div class="post-metadata">

**Author:** ![JordanCClark](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/jordancclark/32/83362_2.png) [@JordanCClark](https://forum.inductiveautomation.com/u/JordanCClark)\
**Post date:** [March 18, 2016, 12:01pm UTC](https://forum.inductiveautomation.com/t/subtract-time-to-date/11384/2 "2016-03-18T12:01:31Z")

</div>

Hi flavien,

You an do this with Java’s Calendar object:

`from java.util import Date, Calendar
now = Calendar.getInstance()
now.add(Calendar.DATE, -1)
yesterday = Date(now.getTimeInMillis())
print yesterday
print system.db.dateFormat(yesterday,"yyyy-MM-dd H:mm:ss")`

---

<div class="post-metadata">

**Author:** ![jim\_lapratt](https://avatars.discourse-cdn.com/v4/letter/j/cc9497/32.png) [@jim\_lapratt](https://forum.inductiveautomation.com/u/jim_lapratt)\
**Post date:** [March 18, 2016, 12:13pm UTC](https://forum.inductiveautomation.com/t/subtract-time-to-date/11384/3 "2016-03-18T12:13:52Z")

</div>

`import time
import datetime
yesterday = datetime.datetime.now() - datetime.timedelta(days=1)
print yesterday`

---

<div class="post-metadata">

**Author:** ![KathyApplebaum](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kathyapplebaum/32/7261_2.png) [@KathyApplebaum](https://forum.inductiveautomation.com/u/KathyApplebaum)\
**Post date:** [March 18, 2016, 1:36pm UTC](https://forum.inductiveautomation.com/t/subtract-time-to-date/11384/4 "2016-03-18T13:36:49Z")

</div>

In 7.8.0 and later, you can also do this:

```auto
print system.date.addDays(system.date.now(), -1)
```

Not sure why the new system.date.\* script functions aren’t in the docs yet… I’ll ping our training dept and see what’s up with that.