# Add incoming data to a DataFrame

**URL:** <https://discourse.julialang.org/t/add-incoming-data-to-a-dataframe/27543>\
**Category:** New to Julia\
**Created:** [August 14, 2019, 3:44pm UTC](https://discourse.julialang.org/t/add-incoming-data-to-a-dataframe/27543 "2019-08-14T15:44:17Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![uwbanjoman](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/uwbanjoman/32/9998_2.png) [@uwbanjoman](https://discourse.julialang.org/u/uwbanjoman)\
**Post date:** [August 14, 2019, 3:44pm UTC](https://discourse.julialang.org/t/add-incoming-data-to-a-dataframe/27543/1 "2019-08-14T15:44:17Z")

</div>

Hi,

I made a DataFrame ab and i want to fill it with incoming data from aa[13].  
aa[13] is incoming data which is refreshed every some time period.  
if I want to push! the current row I’d do this:

julia\> push!(ab,aa[13])  
3×8 DataFrame  
│ Row │ count │ time │ open │ close │ high │ low │ wap │ volume │  
│ │ Int64 │ String │ Float64 │ Float64 │ Float64 │ Float64 │ Float64 │ Int64 │  
├─────┼───────┼────────────────────┼─────────┼─────────┼─────────┼─────────┼─────────┼────────┤  
│ 1 │ 0 │ 20190814 16:45:00 │ 11.8 │ 11.8 │ 11.8 │ 11.8 │ 11.8 │ 0 │  
│ 2 │ 0 │ 20190814 16:48:00 │ 11.86 │ 11.86 │ 11.86 │ 11.86 │ 11.86 │ 0 │  
│ 3 │ 0 │ 20190814 17:31:00 │ 11.9 │ 11.9 │ 11.9 │ 11.9 │ 11.9 │ 0 │

How do i push! the rows that are incoming after that to the df?

---

<div class="post-metadata">

**Author:** ![ElOceanografo](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/eloceanografo/32/624_2.png) [@ElOceanografo](https://discourse.julialang.org/u/ElOceanografo)\
**Post date:** [August 14, 2019, 5:29pm UTC](https://discourse.julialang.org/t/add-incoming-data-to-a-dataframe/27543/2 "2019-08-14T17:29:04Z")

</div>

Welcome @uwbanjoman! Please [make sure to quote your code and and provide a minimum working example](https://discourse.julialang.org/t/psa-make-it-easier-to-help-you/14757)–as is, we can’t tell what `aa[13]` is. What isn’t working for you?

You should be able to `push!` as many new rows as you want:

```julia
using DataFrames
df = DataFrame(a=1, b=2.0)
push!(df, (a=2, b=1.5)) # pushing a NamedTuple
push!(df, [5, 10.0]) # pushing a Vector

```

---

<div class="post-metadata">

**Author:** ![uwbanjoman](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/uwbanjoman/32/9998_2.png) [@uwbanjoman](https://discourse.julialang.org/u/uwbanjoman)\
**Post date:** [August 14, 2019, 5:52pm UTC](https://discourse.julialang.org/t/add-incoming-data-to-a-dataframe/27543/3 "2019-08-14T17:52:42Z")

</div>

Thank you @ElOceanografo

typeof(aa[13]) is  
NamedTuple{(:count, :time, :open, :close, :high, :low, :wap, :volume),Tuple{Int64,String,Float64,Float64,Float64,Float64,Float64,Int64}}  
is coming in let’s say every minute. so if i push this once it gets stored in DataFrame ab.  
works perfectly.

The push! however stores only one NamedTuple: the last one  
but how do i push the next minute NamedTuple, and the next etc.?

I’m thinking something like this. as long NamedTuples keep coming in: store them to the DataFrame,  
unfortunately i do not know how to do that

Jan

---

<div class="post-metadata">

**Author:** ![ElOceanografo](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/eloceanografo/32/624_2.png) [@ElOceanografo](https://discourse.julialang.org/u/ElOceanografo)\
**Post date:** [August 14, 2019, 8:15pm UTC](https://discourse.julialang.org/t/add-incoming-data-to-a-dataframe/27543/4 "2019-08-14T20:15:25Z")

</div>

You will need to `push!` each new `NamedTuple` as it comes in. Where are they coming from/how are you getting the new data?

Note you can surround your code in triple backticks (` ` ```) to make it appear in fixed-width format, which makes it much easier to read.

---

<div class="post-metadata">

**Author:** ![uwbanjoman](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/uwbanjoman/32/9998_2.png) [@uwbanjoman](https://discourse.julialang.org/u/uwbanjoman)\
**Post date:** [August 21, 2019, 4:04pm UTC](https://discourse.julialang.org/t/add-incoming-data-to-a-dataframe/27543/5 "2019-08-21T16:04:39Z")

</div>

```nohighlight
d = Dict{Symbol,Any}()
w = Wrapper(
historicalData= function(reqId::Int, bar::DataFrame)
                      d[:history] = bar
                      println("HistoricalData: $reqId $(size(bar))")
                    end,

historicalDataUpdate= function(reqId::Int, bar::NamedTuple)
                     d[:historyupdate] = bar
                     println("HistoricalDataUpdate: $reqId $bar")
                    end,
)
d, w
end

```

So now i’m trying to get the returned bars from d[:historyupdate] into d[:history]  
by opening a channel.

```julia
historicalDataUpdate= function(reqId::Int, bar::NamedTuple)
                    chnl = Channel(c->println("HistoricalDataUpdate: $reqId $bar"))
                    cc = take!(chnl)
                    push!(d[:history], cc)
                    println("HistoricalDataUpdate: $bar")
                  end,

```

but above method gives me a method error at the take!() function.  
is this a correct solution direction or am i thinking the wrong way, do not understand the matter?

please help

---

<div class="post-metadata">

**Author:** ![ElOceanografo](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/eloceanografo/32/624_2.png) [@ElOceanografo](https://discourse.julialang.org/u/ElOceanografo)\
**Post date:** [August 21, 2019, 7:38pm UTC](https://discourse.julialang.org/t/add-incoming-data-to-a-dataframe/27543/6 "2019-08-21T19:38:51Z")

</div>

I’m still not sure exactly what the data update process is here–can you provide a self-contained example (i.e., one that we can paste into a REPL and have it run, including any `using` statements)? What error are you getting from the `take!` call?

Just reading the code above, it seems likely there’s a simpler way to do what you want. Maybe you could describe more generally what you’re trying to accomplish? Where do the data come from, how often do they update, what do want to do with the `DataFrame` once it’s been updated, etc.?