# Reduce and sum Value ( frequency matrix)

**URL:** https://discourse.julialang.org/t/reduce-and-sum-value-frequency-matrix/46687
**Category:** General Usage
**Tags:** question, dataframes
**Created:** [September 16, 2020, 5:55am UTC](https://discourse.julialang.org/t/reduce-and-sum-value-frequency-matrix/46687 "2020-09-16T05:55:50Z")
**Posts on this page:** 1
**Showing post:** 3

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### Author: ![xiaodai](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/xiaodai/32/15937_2.png) [@xiaodai](https://discourse.julialang.org/u/xiaodai)
#### Post date: [September 16, 2020, 6:17am UTC](https://discourse.julialang.org/t/reduce-and-sum-value-frequency-matrix/46687/3 "2020-09-16T06:17:09Z")

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An MWE would help [Please read: make it easier to help you](https://discourse.julialang.org/t/psa-make-it-easier-to-help-you/14757)

Is this what u mean?

```julia
using DataFrames
using DataConvenience: @> 

@> df begin
  groupby(:USER_ID)
  combine( 1:12 .=> sum)
end

```

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