Re: [matplotlib-devel] Plot or Not: voting to create better matplotlibrc

[Tony Yu <ts...@gm...>]

On Sat, Jul 20, 2013 at 4:47 PM, Chris Beaumont <bea...@ha...> wrote:

> Hi,
>
> I thought I'd chime in on this discussion -- Adrian Price-Whelan and I put
> together plotornot during the SciPy sprints.
>
> I wouldn't advocate for linking to plotornot from matplotlib -- the idea
> is semi tongue-in-cheek, and meant to gauge to what extent there is
> consensus about plot styles. It's not set up to teach about rcParams, nor
> does it systematically explore all possible styles. The votes (>10K, last I
> checked) are saved, and eventually Adrian or I will look over the feedback
> and report back to you all. I haven't had time for that yet. I hope the
> name didn't *actually* offend anyone.
>
> At the risk of sounding unappreciative of MPL (which I love, and rely upon
> daily), I must admit I was disheartened after hearing the MPL devs at SciPy
> discuss styles and defaults. I understand that you don't want to change the
> default styles without a clearly better alternative. I also understand
> that, to some extent, style preferences are subjective. However, there
> seemed to be quite a bit of resistance to the idea that MPL defaults should
> change *at all.*
>
> Even if you ignore the subjective component of this (which I think is a
> mistake, since in my experience there is broad consensus that projects like
> ggplot2, d3, tableau, and spotfire do a "better" job than MPL at styling),
> there are some well-established visual principles that matplotlib violates.
> Some of my biggest pet peeves are:
>
> 1) The default 'axes.color_cycle' values should be equally visible, with
> similar luminance values. The current defaults (bgrcmyk) do not have this
> property -- c and y are harder to see, and thus carry less visual emphasis.
> A color table like the "Dark2" color brewer table (
> http://learnr.files.wordpress.com/2009/04/colours-dark2.png,
> colorbrewer2.org) is more uniform, and carefully designed for visibility
> and contrast. 'rgbcmyk' is clearly an arbitrary choice -- why not use a
> smarter default?
>
> 2) The default 'jet' colormap for images has a lot of poor properties
> (which is even mentioned on the MPL docs at
> http://matplotlib.org/api/pyplot_summary.html#id1). The brain is bad at
> ordering changes in hue (which is bigger -- purple or yellow?), and better
> at ordering changes in intensity or saturation. A colleague of mine
> designed a visualization tool for doctors, and found that the rainbow color
> table had a dramatic negative effect on the effectiveness of the tool (you
> can watch her TED talk about this at
> https://www.youtube.com/watch?v=kU7veyGGps4&t=440s). The jet default is
> especially frustrating, since it *cannot* be modified via rcParams
>

Jet is terrible for so many reasons, but it can be modified (unless I
misunderstand):

image.cmap : gray

I'm all for changing the current defaults.

Cheers,
-Tony