# How to avoid this code duplication?

**URL:** https://discourse.julialang.org/t/how-to-avoid-this-code-duplication/69171
**Category:** New to Julia
**Tags:** plotting, makie
**Created:** [October 4, 2021, 8:58am UTC](https://discourse.julialang.org/t/how-to-avoid-this-code-duplication/69171 "2021-10-04T08:58:46Z")
**Posts on this page:** 2
**Page:** 1

<div class="post-metadata">

### Author: ![Bardo](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/bardo/32/21601_2.png) [@Bardo](https://discourse.julialang.org/u/Bardo)
#### Post date: [October 4, 2021, 8:58am UTC](https://discourse.julialang.org/t/how-to-avoid-this-code-duplication/69171/1 "2021-10-04T08:58:46Z")

</div>

Hi,

The following Makie code appends subplots to existing plots.

 ![Capture](https://global.discourse-cdn.com/julialang/original/3X/9/b/9b415f165628bbe22d65b4ff09fd2f2f8c398f9e.png)

Working, but…

- Code duplication  
was needed for the optional parameter in the first position
- function output  
was needed because mutation of input parameter not possible
- ugly construct to be able to push!

```julia
    if !(typeof(ax) <: Vector)
        ax = [ax]
    end

```

- possibly re-inventing a wheel in Makie.

```julia
using GLMakie
GLMakie.activate!()

function makie_plot(x, y; legends = [], title = [], xlabel = [], ylabel = [])
    m = size(y, 2)
    if isempty(legends)
        legends = ["y$i" for i=1:m]
    end
    # standard colors from matplotlib
    colors = ["#1f77b4", "#ff7f0e", "#2ca02c", "#d62728", "#9467bd", "#8c564b", "#e377c2", "#7f7f7f", "#bcbd22", "#17becf"];
    fig = Figure()
    ax = []
    push!(ax, Axis(fig[1, 1]))
    pl = []
    for i = 1:m
        global pl = lines!(ax[1], x, y[:,i], label = legends[i], color = colors[(i-1)%10+1])
    end
    axislegend(ax)
    if !isempty(title)
        ax[1].title = title
    end
    if !isempty(xlabel)
        ax[1].xlabel = xlabel
    end
    if !isempty(ylabel)
        ax[1].ylabel = ylabel
    end
    display(fig)
    (fig, ax, pl)
end

function makie_append_plot(fap, x, y; legends = [], title = [], xlabel = [], ylabels = [])
    m = size(y, 2)
    if isempty(legends)
        legends = ["y$i" for i=1:m]
    end
    # standard colors from matplotlib
    colors = ["#1f77b4", "#ff7f0e", "#2ca02c", "#d62728", "#9467bd", "#8c564b", "#e377c2", "#7f7f7f", "#bcbd22", "#17becf"];
    fig, ax, pl = fap
    if !(typeof(ax) <: Vector)
        ax = [ax]
    end
    n = length(ax) + 1
    push!(ax, Axis(fig[n, 1]))
    linkxaxes!(ax[1], ax[n])
    for i = 1:m
        lines!(ax[n], x, y[:,i], label = legends[i], color = colors[(i-1)%10+1])
    end
    axislegend(ax[n])
    if !isempty(title)
        ax[1].title = title
    end
    if !isempty(xlabel)
        ax[end].xlabel = xlabel
    end
    hidexdecorations!.(ax[1:n-1], grid=false)
    rowgap!(fig.layout,0)
    display(fig)
    fap = (fig, ax, pl)
end

n = 100; m = 3
x = 1:n
y = randn(n,m)
fap = makie_plot(x,cumsum(y[:,1]), legends = ["cumsum(toto)"])
fap = makie_append_plot(fap, x, y, legends = ["toto", "titi", "tata"])
fap = makie_append_plot(fap, x, y.^2, legends = ["toto2", "titi2", "tata2"], title = "A Title", xlabel = "Time [s]")

```

---

<div class="post-metadata">

### Author: ![Bardo](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/bardo/32/21601_2.png) [@Bardo](https://discourse.julialang.org/u/Bardo)
#### Post date: [October 4, 2021, 10:54am UTC](https://discourse.julialang.org/t/how-to-avoid-this-code-duplication/69171/2 "2021-10-04T10:54:21Z")

</div>

Solved using multiple dispatch, see [makie\_addsubplot](https://discourse.julialang.org/t/makie-multiline-plots-subplots-and-attributes-examples/69113).