# Convert negative to positive and positive to negative

**URL:** <https://discourse.nodered.org/t/convert-negative-to-positive-and-positive-to-negative/70372>\
**Category:** General\
**Tags:** function-node\
**Created:** [10 November 2022 03:54 UTC](https://discourse.nodered.org/t/convert-negative-to-positive-and-positive-to-negative/70372 "2022-11-10T03:54:09Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![DaaD](https://avatars.discourse-cdn.com/v4/letter/d/edb3f5/32.png) [@DaaD](https://discourse.nodered.org/u/DaaD)\
**Post date:** [10 November 2022 03:54 UTC](https://discourse.nodered.org/t/convert-negative-to-positive-and-positive-to-negative/70372/1 "2022-11-10T03:54:09Z")

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Hello,

I have a payload number i need to convert form positive to negative or vice versa. tried to wrap my head around the math javascript but my coding skills are (non existing) are letting me down...

Any pointers will be appreciated.

Need the conversion to make my elec import/export numbers behave the right way!

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<div class="post-metadata">

**Author:** ![DaaD](https://avatars.discourse-cdn.com/v4/letter/d/edb3f5/32.png) [@DaaD](https://discourse.nodered.org/u/DaaD)\
**Post date:** [10 November 2022 04:12 UTC](https://discourse.nodered.org/t/convert-negative-to-positive-and-positive-to-negative/70372/2 "2022-11-10T04:12:00Z")

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I will answer my own question...

After a lot of struggle, this seems to be the simple solution:

```auto
var y = msg.payload;
var x = -y;
msg.payload = x;
return msg;

```

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<div class="post-metadata">

**Author:** ![hotNipi](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/hotnipi/32/383_2.png) [@hotNipi](https://discourse.nodered.org/u/hotNipi)\
**Post date:** [10 November 2022 06:40 UTC](https://discourse.nodered.org/t/convert-negative-to-positive-and-positive-to-negative/70372/3 "2022-11-10T06:40:21Z")

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No need to create extra variables

```auto
msg.payload = msg.payload * -1;
return msg;

```

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<div class="post-metadata">

**Author:** ![DaaD](https://avatars.discourse-cdn.com/v4/letter/d/edb3f5/32.png) [@DaaD](https://discourse.nodered.org/u/DaaD)\
**Post date:** [10 November 2022 13:08 UTC](https://discourse.nodered.org/t/convert-negative-to-positive-and-positive-to-negative/70372/4 "2022-11-10T13:08:10Z")

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Omg! that simple!  
Spend a morning searching to do so!

thanks!

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<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [9 January 2023 13:08 UTC](https://discourse.nodered.org/t/convert-negative-to-positive-and-positive-to-negative/70372/5 "2023-01-09T13:08:21Z")

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