# \`filter\` with \`eachrow\`
**URL:** https://discourse.julialang.org/t/filter-with-eachrow/72466
**Category:** General Usage
**Tags:** iterators
**Created:** [December 2, 2021, 3:51pm UTC](https://discourse.julialang.org/t/filter-with-eachrow/72466 "2021-12-02T15:51:50Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@austinbean](https://discourse.julialang.org/u/austinbean)
#### Post date: [December 2, 2021, 3:51pm UTC](https://discourse.julialang.org/t/filter-with-eachrow/72466/1 "2021-12-02T15:51:50Z")
Suppose I have an array with two columns. I want to `filter` the array based on the values of the first column, but would like what is returned by `filter` to include the second column. This method seems to be missing from `filter`.
Example:
```julia
A = rand(100,2)
filter( x-> x[1]>0.5, eachrow(A))
ERROR: MethodError: no method matching filter(::var"#78#79", ::Base.Generator{Base.OneTo{Int64}, Base.var"#191#192"{Matrix{Float64}}})
```
I can do
```julia
map( x->x[1] > 0.5, eachrow(A))
```
But to do
```julia
A[map( x->x[1] > 0.5, eachrow(A)), :]
```
seems cumbersome. Is there something I’m missing about `filter` or `eachrow` that would make the option directly using `filter` work? Or was this method excluded for a reason I’m not seeing?
---
### Author:  [@josuagrw](https://discourse.julialang.org/u/josuagrw)
#### Post date: [December 2, 2021, 3:53pm UTC](https://discourse.julialang.org/t/filter-with-eachrow/72466/2 "2021-12-02T15:53:21Z")
I believe this is possible with [Iteration utilities · The Julia Language](https://docs.julialang.org/en/v1/base/iterators/#Base.Iterators.filter)
```julia
using Base.Iterators
Iterators.filter( x-> x[1]>0.5, eachrow(A)) |> collect
```
or
```julia
Iterators.filter( x-> x[1]>0.5, eachrow(A)) |>
xs -> mapreduce(transpose, vcat, xs)
```
---
### Author:  [@rafael.guerra](https://discourse.julialang.org/u/rafael.guerra)
#### Post date: [December 2, 2021, 5:04pm UTC](https://discourse.julialang.org/t/filter-with-eachrow/72466/3 "2021-12-02T17:04:43Z")
> [@austinbean](#):
>
> `filter( x-> x[1]>0.5, eachrow(A))`
The following seems to get the job done too:
```julia
filter.(x-> x[1]>0.5, Ref(collect(eachrow(A))))
```
---
### Author:  [@Seif\_Shebl](https://discourse.julialang.org/u/Seif_Shebl)
#### Post date: [December 2, 2021, 7:51pm UTC](https://discourse.julialang.org/t/filter-with-eachrow/72466/4 "2021-12-02T19:51:56Z")
There are other options, but this seems short and is twice as fast:
```julia
A[view(A,:,1).>0.5, :]
```
---
### Author:  [@austinbean](https://discourse.julialang.org/u/austinbean)
#### Post date: [December 2, 2021, 8:43pm UTC](https://discourse.julialang.org/t/filter-with-eachrow/72466/5 "2021-12-02T20:43:16Z")
Great answers. Thanks. The first one seems closest to what I needed.
---
### Author:  [@aplavin](https://discourse.julialang.org/u/aplavin)
#### Post date: [December 2, 2021, 11:28pm UTC](https://discourse.julialang.org/t/filter-with-eachrow/72466/6 "2021-12-02T23:28:02Z")
Just use `splitdims` instead of `eachrow`: it returns a vector and supports `filter`.
```julia
using SplitApplyCombine
filter(x->x[1]>0.5, splitdims(A, 1))
```
or `splitdimsview` to get views instead of copies.