# Sum function of two sensor data

**URL:** https://discourse.nodered.org/t/sum-function-of-two-sensor-data/11761
**Category:** General
**Created:** [2 June 2019 11:35 UTC](https://discourse.nodered.org/t/sum-function-of-two-sensor-data/11761 "2019-06-02T11:35:49Z")
**Posts on this page:** 1
**Showing post:** 6

<div class="post-metadata">

### Author: ![b3hzad2012](https://avatars.discourse-cdn.com/v4/letter/b/a9a28c/32.png) [@b3hzad2012](https://discourse.nodered.org/u/b3hzad2012)
#### Post date: [2 June 2019 16:45 UTC](https://discourse.nodered.org/t/sum-function-of-two-sensor-data/11761/6 "2019-06-02T16:45:46Z")

</div>

I've read this:

> [@How to do a simple sum of 2 msgs](https://discourse.nodered.org/t/how-to-do-a-simple-sum-of-2-msgs/5382):
>
> Hello, Im working in my final paper and I find myself in a situation I cant solve a simple sum of two mqtt messages. Could someone help-me?

but it doesn't work.

 ![Capture](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/2X/2/2c1ecc16f415420b923707ea2bd071da310e6d73.png)  
How can I use it?

```auto
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```

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