Here is an opinionated version. Feel free to criticize:

Subsections for Plots

Brief overview of the JuliaPlots ecosystem

• JuliaPlots Organization
• Plots.jl (what is it good for and what are its limitations)
• Makie.jl (what is it good for and what are its limitations)
• AlgebraOfGraphics.jl (what is it good for and what are its limitations) (version 2.0)

1. What is Plots.jl?

   • plot vs plot!
   • input data
   • Series Types and functions(e.g. line, line!, heatmap, heatmap!)
   • How to save a plot

2. Attributes

   • Overview (What are attributes, and the whole symbol e.g. :xticks system)
   • Series attributes
   • Plot Attributes
   • Footnote about the extra_kwargs stuff
   • Examples using the most common things that you want to do in a visualization. This could be inserted right after you introduce a specific attribute.

3. Color and Palettes I think we should cover colorbrewer and the ones from matplotlib (inferno, viridis, magma). We should cover some stuff from the Claus Wilke Fundamentals of Data Visualization book (Chapters 4 and 19). Also we should cover the three types of color usage:

   1. sequential: continuous stuff, e.g. :blues (only blue)
   2. diverging: continuous stuff, e.g. :RdBu (from red to blue)
   3. distinguishable: discrete stuff, e.g. :Set1_5

   I have a very strong positive bias towards colorbrewer Sets (e.g. palette=:Set1_5).

   We should also mention that the reader should use a colorblinded-friendly palette or colors. Maybe we should include an official statistics regarding the prevalence of any sort of colorblindness or color difficulties in the population. I remember seeing somewhere that it was around 5% of people.

4. Layouts

   • Overview on several ways to do layouts
   • the layout argument, also cover the grid
   • the @layout macro
   • specific measures with the Plots.PlotMeasures submodule
   • adding subplots incremententally. Define p1, p2, p3; then do a plot(p1, p2, p3; layout=l)

This PR add code to generate the full cover. See https://github.com/JuliaDataScience/JuliaDataScience/issues/17#issuecomment-927185934 for more information about the dimensions.

I don't consider the cover done and perfect now. It is meant as a place where we can start discussing the appearance.

Preview

EDIT: This wasn't working in Amazon. It was turned into

So, instead using the Amazon cover editor:

which is turned into

Hi,

I get an

ERROR: LoadError: UndefVarError: Downloads not defined
Stacktrace:
 [1] top-level scope
   @ o:\Julia\makie.jl:604
in expression starting at o:\Julia\makie.jl:604

Commented out.

And on execution for all demo functions:

ERROR: UndefVarError: Options not defined
Stacktrace:
 [1] custom_plot()
   @ Main o:\Julia\makie.jl:16
 [2] top-level scope
   @ REPL[12]:1

Commented out.

On execution,

custom_plot()

no error, no plot appears.

There is a link broken in Chapter 7 datavisMakie.md:

In the "See Makie’s documentation for more." It redirects to http://makie.juliaplots.org/stable/backends_and_output.html#Backends-and-Output which is broken.

cc @lazarusA

Notation discussion points from #20:

1. Always using : before the start of a code block.
2. Mentioning functions like DataFrame as DataFrame() or DataFrame(...).
3. My suggestion: only Julia objects between backticks and filenames and extension names between quotation marks (like Julia's strings).

The lines

https://github.com/JuliaDataScience/JuliaDataScience/blob/b5582d29a9afa300e0a124ad2820389c386c04cc/contents/dataframes_select.md#L48-L56

don't give the same result as the previous example ... (where :id is not shown)

I think you need to rephrase the text.

this should fix some alignment issues regarding the pipes. Additionally, I did a print for the previous one and the lack of grid lines makes the whole cover a little bit dull.

I have put an issue on Stack Overflow about an example of this book. Could you please explain? https://stackoverflow.com/questions/70321085/julia-cannot-reproduce-the-rand

Many thanks.

Shixiang

For a discussion see issue #221 that it is beneficial to have unnumbered sections when there are no other sections on that level, i.e. that there is no other "section x.2".

There is only the instance

https://github.com/JuliaDataScience/JuliaDataScience/blob/2c750e092b7aa932cf10d7fc12f1d0f7ba7ae909/contents/julia_basics.md#L671

which cannot be made unnumbered, because it is referenced at

https://github.com/JuliaDataScience/JuliaDataScience/blob/2c750e092b7aa932cf10d7fc12f1d0f7ba7ae909/contents/dataframes_performance.md#L9

My suggestion is to bring this one level up, i.e.

- #### Functions with a bang `!` {#sec:function_bang}
+ ### Functions with a bang `!` {#sec:function_bang}

I think that also fits to the previous section header where I (with my current n00bie understanding) don't see the "bang operator" fitting in.

Do you agree? If yes, I would prepare another commit. Otherwise you can merge the PR directly.

We need a logo I will talk to someone who can do that for me at UNINOVE. Any thoughts @rikhuijzer ? We should move anything stats/Bayesian so to not confuse with future endeavors.

Maybe something with Tabular Data or Line Plots. We should definitely use Julia colors.

• [x] Update JuliaDataScience GitHub Organization Logo
• [x] Update JuliaDataScience Book favicon site icon

As I already stated in e.g. https://github.com/JuliaDataScience/JuliaDataScience/pull/215/commits/e8e1d11ed6386f8bcd552abbfd9ab058c3176b51 it would nice to make some sections unnumbered when there is no second section on that level.

When I have seen this correct, this should be possible by appending the section entry by {-} as e.g. can be seen in

https://github.com/JuliaDataScience/JuliaDataScience/blob/56151f0f6d69ad4c62945aa1deb3169af90ef9ad/contents/index.md#L1

So if you consider it would be nice to have that I'll redo the suggestions in a new PR. Especially if it is that easily doable.

PS:
I am not sure if my newest comments in #217 have been noticed by one of you, since I have added them after the PR was merged. Thank you for your comments!

Some suggested changes to the CairoMakie cheatsheet, some for consistency and some to make it easier to understand what the function actually does (I think that is the main use of this figure: once the purpose of a plotting function is clear, the user can always check the documentation for the different ways to call the function). The biggest change is for linesegments: it now uses the linesegments(x, y) signature with the same data as the previous plots, to help understanding what's going on.

Full list of changes:

• change range of first plots to have even number of points (for linesegments)
• change linesegments to use same data as previous plots
• uniformize parameter names in plot titles
• use variable heights in crossbar
• fix title of violin plot
• more explicit title for mesh

Hi,

Using Julia 1.8.1, VS Code notebooks

Entering the code from 4.1.2 Excel, I tried running: path = write_grades_xlsx() xf = readxlsx(path)

which gave: MethodError: objects of type Vector{String} are not callable Use square brackets [] for indexing an Array.

Stacktrace: [1] write_xlsx(name::String, df::DataFrame) @ Main ~/julia-test/juliadatascience-dataframes.ipynb:4 [2] write_grades_xlsx() @ Main ~/julia-test/juliadatascience-dataframes.ipynb:3 [3] top-level scope @ ~/julia-test/juliadatascience-dataframes.ipynb:1

Here's the function: function write_xlsx(name, df::DataFrame) path = "$name.xlsx" data = collect(eachcol(df)) cols = names(df) writetable(path, data, cols) end

I found that because you had defined a "names" variable earlier in the chapter, this clobbered the "names()" function. When I changed this to use Base.names(), everything worked properly. (Somewhat ironically, you mentioned the global variable problem just after defining "names". ;-))

I'd recommend just renaming "names" to something less ambiguous, and then it won't break the code below.

Thanks for the great work! Ari

After this first experience of doing and printing the book I still feel that the margins [text at the edges] and overall book size is not an appropriate layout. Thoughts?