# dateArithmetic function not defined?

**URL:** <https://forum.inductiveautomation.com/t/datearithmetic-function-not-defined/6877>\
**Category:** Ignition\
**Created:** [July 17, 2013, 4:06pm UTC](https://forum.inductiveautomation.com/t/datearithmetic-function-not-defined/6877 "2013-07-17T16:06:41Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![bpirtle](https://avatars.discourse-cdn.com/v4/letter/b/858c86/32.png) [@bpirtle](https://forum.inductiveautomation.com/u/bpirtle)\
**Post date:** [July 17, 2013, 4:06pm UTC](https://forum.inductiveautomation.com/t/datearithmetic-function-not-defined/6877/1 "2013-07-17T16:06:41Z")

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I am using version 7.5.5 (b1255) and I am trying to use the following date arithmetic:

import datetime

print dateArithmetic(toDate(“2010-01-04 8:00:00”), 5, “hour”)

I also tried it without the import and both versions give me the following error: “name ‘dateArithmetic’ is not defined”, and this was copied directly from the manual. Is dateArithmetic no longer supported?

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<div class="post-metadata">

**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [July 17, 2013, 4:23pm UTC](https://forum.inductiveautomation.com/t/datearithmetic-function-not-defined/6877/2 "2013-07-17T16:23:27Z")

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Sounds like you’re trying to use an expression function inside a jython script.

You should be able to do arithmetic in jython pretty easily: [docs.python.org/2/library/datetime.html](http://docs.python.org/2/library/datetime.html)