# Error message for not inputting an ordered pair

**URL:** https://cl.desmos.com/t/error-message-for-not-inputting-an-ordered-pair/4972
**Category:** Questions
**Created:** [July 1, 2023, 4:52pm UTC](https://cl.desmos.com/t/error-message-for-not-inputting-an-ordered-pair/4972 "2023-07-01T16:52:31Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![Andy\_Malbouef](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/andy_malbouef/32/3345_2.png) [@Andy\_Malbouef](https://cl.desmos.com/u/Andy_Malbouef)
#### Post date: [July 1, 2023, 4:52pm UTC](https://cl.desmos.com/t/error-message-for-not-inputting-an-ordered-pair/4972/1 "2023-07-01T16:52:31Z")

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Can anyone help with giving an error message to students when they do **not** enter an ordered pair into a table cell? In other words, force them to enter an ordered pair?

> **[Error message : not ordered pair • Activity Builder by Desmos](https://teacher.desmos.com/activitybuilder/custom/64a058057d97bd0f5679e3dc)**
>
> by Andy Malbouef

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### Author: ![sergeballif](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/sergeballif/32/231_2.png) [@sergeballif](https://cl.desmos.com/u/sergeballif)
#### Post date: [July 3, 2023, 1:35am UTC](https://cl.desmos.com/t/error-message-for-not-inputting-an-ordered-pair/4972/2 "2023-07-03T01:35:42Z")

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I messed around with it for a while. I overcomplicated it by adding a randomization piece that you didn’t ask for, but here it is anyway so you can see some options. [[Copy of] Error message : not ordered pair • Activity Builder by Desmos](https://teacher.desmos.com/activitybuilder/custom/64a21a30117843ee64e16479)

I don’t know where you got the submitButtonText sink because I don’t see it in the documentation. Perhaps I just missed it. I added a separate button. I passed the table input to a hidden graph and then parsed the point and passed it to the calculator to check whether the values matched and whether a point was entered. I disabled the button when the table input is not a point.

I would caution that you should be careful when checking against the exact string of the input in general because a student might enter “(+3,+4)” instead of “(3,4)” and get marked wrong. That’s why it is recommended to check the actual value of the coordinates for correctness.

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### Author: ![Daniel\_Wekselgreene](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/daniel_wekselgreene/32/1819_2.png) [@Daniel\_Wekselgreene](https://cl.desmos.com/u/Daniel_Wekselgreene)
#### Post date: [July 3, 2023, 2:56am UTC](https://cl.desmos.com/t/error-message-for-not-inputting-an-ordered-pair/4972/3 "2023-07-03T02:56:45Z")

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You can use parseOrderedPair to do this most easily. Here’s an example: [[Copy of] Error message : not ordered pair • Activity Builder by Desmos](https://teacher.desmos.com/activitybuilder/custom/64a238310420555644f6e424)

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### Author: ![Andy\_Malbouef](https://yyz1.discourse-cdn.com/flex031/user_avatar/cl.desmos.com/andy_malbouef/32/3345_2.png) [@Andy\_Malbouef](https://cl.desmos.com/u/Andy_Malbouef)
#### Post date: [July 3, 2023, 4:47pm UTC](https://cl.desmos.com/t/error-message-for-not-inputting-an-ordered-pair/4972/4 "2023-07-03T16:47:32Z")

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Thanks, Serge and Daniel!