# How to create a new DF with only the rows that contain specific values from two different columns

**URL:** <https://discourse.julialang.org/t/how-to-create-a-new-df-with-only-the-rows-that-contain-specific-values-from-two-different-columns/119431>\
**Category:** New to Julia\
**Tags:** question\
**Created:** [September 15, 2024, 1:29pm UTC](https://discourse.julialang.org/t/how-to-create-a-new-df-with-only-the-rows-that-contain-specific-values-from-two-different-columns/119431 "2024-09-15T13:29:25Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![cocarroll1](https://avatars.discourse-cdn.com/v4/letter/c/edb3f5/32.png) [@cocarroll1](https://discourse.julialang.org/u/cocarroll1)\
**Post date:** [September 15, 2024, 1:29pm UTC](https://discourse.julialang.org/t/how-to-create-a-new-df-with-only-the-rows-that-contain-specific-values-from-two-different-columns/119431/1 "2024-09-15T13:29:25Z")

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I want to create a new DF (e.g. df\_2) based on an existing one (e.g. df\_1) which has 9 columns and multiple rows of data. In this new df\_2 I want to have all the data from each row, only when the values from 1 column (e.g. :AMT) equal 10, and the values from a second column equal “NORMAL”

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**Author:** ![drizk1](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/drizk1/32/208422_2.png) [@drizk1](https://discourse.julialang.org/u/drizk1)\
**Post date:** [September 15, 2024, 1:40pm UTC](https://discourse.julialang.org/t/how-to-create-a-new-df-with-only-the-rows-that-contain-specific-values-from-two-different-columns/119431/2 "2024-09-15T13:40:49Z")

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with TidierData.jl you could do the following

```julia
using TidierData

julia> df_1 = DataFrame(
           ID = 1:7,
           Name = ["Alice", "Bob", "Charlie", "David", "Eva", "Frank", "Grace"],
           AMT = [10, 20, 10, 15, 10, 10, 25],
           Status = ["NORMAL", "ABNORMAL", "NORMAL", "NORMAL", "NORMAL", "ABNORMAL", "NORMAL"],
           Score = [95, 85, 92, 88, 76, 89, 91],
           Date = ["2024-01-01", "2024-02-01", "2024-03-01", "2024-04-01", "2024-05-01", "2024-06-01", "2024-07-01"],
           Category = ["A", "B", "A", "C", "B", "A", "C"],
           Amount = [1000, 1500, 1000, 2000, 1000, 1500, 2000],
           Type = ["X", "Y", "X", "Y", "X", "Y", "X"]
       );

julia> df_2 = @filter(df_1, AMT == 10 && Status == "NORMAL")
3×9 DataFrame
 Row │ ID Name AMT Status Score Date Category Amount Type   
     │ Int64 String Int64 String Int64 String String Int64 String 
─────┼────────────────────────────────────────────────────────────────────────────
   1 │ 1 Alice 10 NORMAL 95 2024-01-01 A 1000 X
   2 │ 3 Charlie 10 NORMAL 92 2024-03-01 A 1000 X
   3 │ 5 Eva 10 NORMAL 76 2024-05-01 B 1000 X

```

Not shown here is TidierData a `@chain` with multiple sequential manipulations

```julia
@chain df_1 begin
     @filter( AMT == 10 && Status == "NORMAL")
# other data manipulations
end

```

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<div class="post-metadata">

**Author:** ![cocarroll1](https://avatars.discourse-cdn.com/v4/letter/c/edb3f5/32.png) [@cocarroll1](https://discourse.julialang.org/u/cocarroll1)\
**Post date:** [September 15, 2024, 2:08pm UTC](https://discourse.julialang.org/t/how-to-create-a-new-df-with-only-the-rows-that-contain-specific-values-from-two-different-columns/119431/3 "2024-09-15T14:08:53Z")

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When I tried this

```julia
julia> df_2 = @filter(df_1, AMT == 10 && Status == "NORMAL")

```

I get an error that @filter is undefined. As an aside, why no colon before AMT i.e. :AMT not AMT and the same for Status

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<div class="post-metadata">

**Author:** ![TimG](https://avatars.discourse-cdn.com/v4/letter/t/82dd89/32.png) [@TimG](https://discourse.julialang.org/u/TimG)\
**Post date:** [September 15, 2024, 2:09pm UTC](https://discourse.julialang.org/t/how-to-create-a-new-df-with-only-the-rows-that-contain-specific-values-from-two-different-columns/119431/4 "2024-09-15T14:09:28Z")

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Or just use `subset()`

```julia
using DataFrames
df_1 = DataFrame(
           ID = 1:7,
           Name = ["Alice", "Bob", "Charlie", "David", "Eva", "Frank", "Grace"],
           AMT = [10, 20, 10, 15, 10, 10, 25],
           Status = ["NORMAL", "ABNORMAL", "NORMAL", "NORMAL", "NORMAL", "ABNORMAL", "NORMAL"],
           Score = [95, 85, 92, 88, 76, 89, 91],
           Date = ["2024-01-01", "2024-02-01", "2024-03-01", "2024-04-01", "2024-05-01", "2024-06-01", "2024-07-01"],
           Category = ["A", "B", "A", "C", "B", "A", "C"],
           Amount = [1000, 1500, 1000, 2000, 1000, 1500, 2000],
           Type = ["X", "Y", "X", "Y", "X", "Y", "X"]
       )
df_2 = subset(df_1, [:AMT, :Status] => ByRow((x, y) -> x==10 && y == "NORMAL"))

```

```julia
3×9 DataFrame
 Row │ ID Name AMT Status Score Date Category Amount Type   
     │ Int64 String Int64 String Int64 String String Int64 String 
─────┼────────────────────────────────────────────────────────────────────────────
   1 │ 1 Alice 10 NORMAL 95 2024-01-01 A 1000 X
   2 │ 3 Charlie 10 NORMAL 92 2024-03-01 A 1000 X
   3 │ 5 Eva 10 NORMAL 76 2024-05-01 B 1000 X

```

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<div class="post-metadata">

**Author:** ![drizk1](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/drizk1/32/208422_2.png) [@drizk1](https://discourse.julialang.org/u/drizk1)\
**Post date:** [September 15, 2024, 2:25pm UTC](https://discourse.julialang.org/t/how-to-create-a-new-df-with-only-the-rows-that-contain-specific-values-from-two-different-columns/119431/5 "2024-09-15T14:25:09Z")

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I am not sure why you might be getting that error. If you have previously loaded another package that has `@filter` you may need to preface it as `TidierData.@filter` if there is a namespace conflict

but otherwise

```julia
using TidierData

```

should enable it.

As for the lack of `:`, TidierData enables the use of bare column names throughout all of its macros allowing for a clean interface.

This [brief explanation](https://dataframes.juliadata.org/dev/man/querying_frameworks/#TidierData.jl) talks a little bit about some of the design choices in TidierData.jl

---

<div class="post-metadata">

**Author:** ![cocarroll1](https://avatars.discourse-cdn.com/v4/letter/c/edb3f5/32.png) [@cocarroll1](https://discourse.julialang.org/u/cocarroll1)\
**Post date:** [September 15, 2024, 2:28pm UTC](https://discourse.julialang.org/t/how-to-create-a-new-df-with-only-the-rows-that-contain-specific-values-from-two-different-columns/119431/6 "2024-09-15T14:28:42Z")

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Ok, that explains it I hadn’t loaded that package. works now thanks