<meta http-equiv="Content-Type" content="text/html; charset=utf-8"><div dir="ltr">I am in favor of retraining a unique yt colormap but making it work better than algae for the reasons already mentioned. I'd like to point out that about a year ago I added the capacity in yt to create custom colormaps that could easily be used for this purpose.<div><br></div><div><a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__yt-2Dproject.org_docs_dev_visualizing_colormaps_index.html-3Fhighlight-3Dcolormaps-23making-2Dand-2Dviewing-2Dcustom-2Dcolormaps&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=IbjL4oi_d927aVp0WUg1u9h7LiI6yB5XUFXBVweFya0&s=6vYzYM66RUk3i-bvqCVnSObV-YK0eTKBL9hy6Hzvn8E&e=">http://yt-project.org/docs/dev/visualizing/colormaps/index.html?highlight=colormaps#making-and-viewing-custom-colormaps</a><br></div><div><br></div><div>Cameron</div></div><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Jan 6, 2016 at 1:48 PM, Levy, Stuart A <span dir="ltr"><<a href="mailto:salevy@illinois.edu" target="_blank">salevy@illinois.edu</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div>
<div style="direction:ltr;font-family:Tahoma;color:#000000;font-size:10pt">There was a fair bit of discussion about colormaps - terrible, useful, beautiful - at IEEE Vis last October. The viridis colormap was a featured one. So was the traditional
rainbow, which lots of info-vis and perceptual people piled on to criticize.<br>
<br>
Among design criteria for a continuous-valued colormap is whether it's "sequential" (like the typical yt colormap, or viridis) or "diverging". You'd want a diverging colormap to show signed deviations from a norm - where the eye should be caught by places
where a value is either much less than, or much more than, something in the middle. Is it worth offering a typical divergent colormap, as well as a new typical sequential one, in yt?<br>
<br>
Note that among the Stefan van der Walt & Nathaniel Smith writeup ( <a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__bids.github.io_colormap_&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=IbjL4oi_d927aVp0WUg1u9h7LiI6yB5XUFXBVweFya0&s=sJvvZYZl8pJRPFOQgiRutpXNiSsYRH5COXczNCgPmjM&e=" target="_blank">
http://bids.github.io/colormap/</a> ) on their development of better cmaps, they use Nathan Goldbaum's galaxy evolution as a test case for six (sequential) examples! =>
<a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__vorpus.org_-7Enjs_goldbaum-2Dgalaxies-2Dall-2Dcolormaps.mkv&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=IbjL4oi_d927aVp0WUg1u9h7LiI6yB5XUFXBVweFya0&s=A9tB_qZjzX9JBcj-GqtidnzzomrFILaMhIJ4Zn0IqSE&e=" target="_blank">
http://vorpus.org/~njs/goldbaum-galaxies-all-colormaps.mkv</a> <br>
<br>
A neat web site with sample colormaps - aimed at mapping discrete values on geographic maps, so not directly applicable but cool - is this, by Cynthia Brewer and Mark Harrower at PSU:<br>
<a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__colorbrewer2.org_&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=IbjL4oi_d927aVp0WUg1u9h7LiI6yB5XUFXBVweFya0&s=Qz0tgWpFV3570ChbIBPI7-DfajilGbautNVwtsKxLDw&e=" target="_blank">http://colorbrewer2.org/</a><br>
It has a library of predesigned cmaps, and lets you sift them by being colorblind-safe, photocopy safe, etc.<br>
<div style="font-family:Times New Roman;color:#000000;font-size:16px">
<hr>
<div style="direction:ltr"><font color="#000000" face="Tahoma" size="2"><b>From:</b> yt-dev [<a href="mailto:yt-dev-bounces@lists.spacepope.org" target="_blank">yt-dev-bounces@lists.spacepope.org</a>] on behalf of B.W. Keller [<a href="mailto:kellerbw@mcmaster.ca" target="_blank">kellerbw@mcmaster.ca</a>]<br>
<b>Sent:</b> Wednesday, January 06, 2016 12:13<br>
<b>To:</b> <a href="mailto:yt-dev@lists.spacepope.org" target="_blank">yt-dev@lists.spacepope.org</a><br>
<b>Subject:</b> Re: [yt-dev] Default colormap<br>
</font><br>
</div><div><div class="h5">
<div></div>
<div>
<div dir="ltr">There is a really excellent paper on designing color maps called "Color Sequences for Univariate Maps: Theory, Experiments, and Principles" that you can get here: <a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__ccom.unh.edu_sites_default_files_publications_Ware-5F1988-5FCGA-5FColor-5Fsequences-5Funivariate-5Fmaps.pdf&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=FMHeB3pNOAeqOzZIyPgy5-uxuN2ghGC9-8XQuthPiIU&s=5Yg0N-A3hbVCKwltZjUQBJOQZK6OFbo4G3VWKT9uVZ0&e=" target="_blank">http://ccom.unh.edu/sites/default/files/publications/Ware_1988_CGA_Color_sequences_univariate_maps.pdf</a>
<div><br>
</div>
<div>If we design a new colormap, this would be a good reference along with those scipy resources. I personally would love to have an accessible, yt-custom colormap.<br>
<div class="gmail_extra"><br>
<div class="gmail_quote">On Wed, Jan 6, 2016 at 11:50 AM, Erik Schnetter <span dir="ltr">
<<a href="mailto:schnetter@gmail.com" target="_blank">schnetter@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">
I think there are several colourmaps that were created when Viridis<br>
was invented. I personally like Inferno.<br>
<br>
-erik<br>
<div>
<div><br>
On Wed, Jan 6, 2016 at 11:34 AM, Nathan Goldbaum <<a href="mailto:nathan12343@gmail.com" target="_blank">nathan12343@gmail.com</a>> wrote:<br>
> I would also be for coming up with our own colormap. That said, I think<br>
> simply modifying algae won't be enough, since it is too perceptually<br>
> nonlinear.<br>
><br>
> On Wed, Jan 6, 2016 at 10:32 AM, John ZuHone <<a href="mailto:jzuhone@gmail.com" target="_blank">jzuhone@gmail.com</a>> wrote:<br>
>><br>
>> I would go for modifying algae.<br>
>><br>
>> > On Jan 6, 2016, at 11:30 AM, Matthew Turk <<a href="mailto:matthewturk@gmail.com" target="_blank">matthewturk@gmail.com</a>> wrote:<br>
>> ><br>
>> > Hi folks,<br>
>> ><br>
>> > For a long time we've used "algae," which was designed by Britton<br>
>> > about eight years ago, as the default colormap. This has been really<br>
>> > nice for "branding" yt -- if you see an algae plot, it's probably (not<br>
>> > definitely) made with yt. But it's also not accessible from a<br>
>> > colorblindness perspective. Stefan van der Walt has been giving some<br>
>> > really great talks lately about building a better colormap for<br>
>> > matplotlib (e.g., <a href="https://urldefense.proofpoint.com/v2/url?u=https-3A__www.youtube.com_watch-3Fv-3DxAoljeRJ3lU&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=FMHeB3pNOAeqOzZIyPgy5-uxuN2ghGC9-8XQuthPiIU&s=fpeIMGnkAI5_PfL699BNCowLgIQr4xXy-oK90Bub2MU&e=" rel="noreferrer" target="_blank">
https://www.youtube.com/watch?v=xAoljeRJ3lU</a> ) which<br>
>> > culminated in viridis, which is shipping in recent versions of<br>
>> > matplotlib and will become the default.<br>
>> ><br>
>> > In support of this, he built a tool called viscm which can generate<br>
>> > reduced versions of colormaps to show what they would be like with<br>
>> > varying degrees of insensitivity to color. I've generated outputs<br>
>> > from viscm of three of the custom colormaps we ship with yt:<br>
>> ><br>
>> > Algae: <a href="https://urldefense.proofpoint.com/v2/url?u=https-3A__images.hub.yt_u_fido_m_d275d5e1-2Dpng_&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=FMHeB3pNOAeqOzZIyPgy5-uxuN2ghGC9-8XQuthPiIU&s=5En_z8QNwijy3Ou9Ah6_Fzfdp8gSXcs4bphf-SZBGuE&e=" rel="noreferrer" target="_blank">
https://images.hub.yt/u/fido/m/d275d5e1-png/</a><br>
>> > Cubehelix: <a href="https://urldefense.proofpoint.com/v2/url?u=https-3A__images.hub.yt_u_fido_m_8e698928-2Dpng_&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=FMHeB3pNOAeqOzZIyPgy5-uxuN2ghGC9-8XQuthPiIU&s=y4k79vB300hkxSOvNBPaMYSeMSdgWY3yJP2TJ1e61YA&e=" rel="noreferrer" target="_blank">
https://images.hub.yt/u/fido/m/8e698928-png/</a> (I believe<br>
>> > this is now also shipped with MPL)<br>
>> > Kamae: <a href="https://urldefense.proofpoint.com/v2/url?u=https-3A__images.hub.yt_u_fido_m_e0e40efa-2Dpng_&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=FMHeB3pNOAeqOzZIyPgy5-uxuN2ghGC9-8XQuthPiIU&s=xvnX_JDGJFjLaPam1gf5BwfAS4lF7qjJ5CLmd6ExJzQ&e=" rel="noreferrer" target="_blank">
https://images.hub.yt/u/fido/m/e0e40efa-png/</a><br>
>> ><br>
>> > I love algae, but it's not the best from an accessibility perspective.<br>
>> ><br>
>> > I'd like to propose that we use a new default colormap. If we do<br>
>> > this, I see two options:<br>
>> ><br>
>> > * Retain a "branding" by developing a new one either by using the<br>
>> > techniques used by matplotlib (or one of the maps they opted not to<br>
>> > use) or by modifying algae to be more accessible; looking at the<br>
>> > response functions, I suspect it would be reasonably possible to<br>
>> > modify it. (Modifying algae is my preference.)<br>
>> > * Use viridis (which we may then have to ship if we have older<br>
>> > versions of matplotlib to support)<br>
>> ><br>
>> > -Matt<br>
>> > _______________________________________________<br>
>> > yt-dev mailing list<br>
>> > <a href="mailto:yt-dev@lists.spacepope.org" target="_blank">yt-dev@lists.spacepope.org</a><br>
>> > <a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.spacepope.org_listinfo.cgi_yt-2Ddev-2Dspacepope.org&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=FMHeB3pNOAeqOzZIyPgy5-uxuN2ghGC9-8XQuthPiIU&s=BaeHL9R3SqrWDRh-sTc8pLPmBg83iPA2WHUwC8XJkdM&e=" rel="noreferrer" target="_blank">
http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org</a><br>
>><br>
>> _______________________________________________<br>
>> yt-dev mailing list<br>
>> <a href="mailto:yt-dev@lists.spacepope.org" target="_blank">yt-dev@lists.spacepope.org</a><br>
>> <a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.spacepope.org_listinfo.cgi_yt-2Ddev-2Dspacepope.org&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=FMHeB3pNOAeqOzZIyPgy5-uxuN2ghGC9-8XQuthPiIU&s=BaeHL9R3SqrWDRh-sTc8pLPmBg83iPA2WHUwC8XJkdM&e=" rel="noreferrer" target="_blank">
http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org</a><br>
><br>
><br>
><br>
> _______________________________________________<br>
> yt-dev mailing list<br>
> <a href="mailto:yt-dev@lists.spacepope.org" target="_blank">yt-dev@lists.spacepope.org</a><br>
> <a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.spacepope.org_listinfo.cgi_yt-2Ddev-2Dspacepope.org&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=FMHeB3pNOAeqOzZIyPgy5-uxuN2ghGC9-8XQuthPiIU&s=BaeHL9R3SqrWDRh-sTc8pLPmBg83iPA2WHUwC8XJkdM&e=" rel="noreferrer" target="_blank">
http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org</a><br>
><br>
<br>
<br>
<br>
</div>
</div>
<span><font color="#888888">--<br>
Erik Schnetter <<a href="mailto:schnetter@gmail.com" target="_blank">schnetter@gmail.com</a>><br>
<a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__www.perimeterinstitute.ca_personal_eschnetter_&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=FMHeB3pNOAeqOzZIyPgy5-uxuN2ghGC9-8XQuthPiIU&s=7jImD2ypg2lTI_MTSODmVdgQnwBMJvGou2W8_PSAADg&e=" rel="noreferrer" target="_blank">http://www.perimeterinstitute.ca/personal/eschnetter/</a><br>
</font></span>
<div>
<div>_______________________________________________<br>
yt-dev mailing list<br>
<a href="mailto:yt-dev@lists.spacepope.org" target="_blank">yt-dev@lists.spacepope.org</a><br>
<a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.spacepope.org_listinfo.cgi_yt-2Ddev-2Dspacepope.org&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=FMHeB3pNOAeqOzZIyPgy5-uxuN2ghGC9-8XQuthPiIU&s=BaeHL9R3SqrWDRh-sTc8pLPmBg83iPA2WHUwC8XJkdM&e=" rel="noreferrer" target="_blank">http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org</a><br>
</div>
</div>
</blockquote>
</div>
<br>
</div>
</div>
</div>
</div>
</div></div></div>
</div>
</div>
<br>_______________________________________________<br>
yt-dev mailing list<br>
<a href="mailto:yt-dev@lists.spacepope.org">yt-dev@lists.spacepope.org</a><br>
<a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.spacepope.org_listinfo.cgi_yt-2Ddev-2Dspacepope.org&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=IbjL4oi_d927aVp0WUg1u9h7LiI6yB5XUFXBVweFya0&s=qNLs7tKLpNxjZ9lfT7CXuLZ5voQYQ4kCEHXZiGSgrPc&e=" rel="noreferrer" target="_blank">http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org</a><br>
<br></blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature"><div dir="ltr"><div>Cameron Hummels<div><span style="font-size:12.8000001907349px">NSF Postdoctoral Fellow</span></div><div><span style="font-size:12.8000001907349px">Department of Astronomy</span></div><div><span style="font-size:12.8000001907349px">California Institute of Technology</span><br></div><div><a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__chummels.org&d=BQMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=hgcBC3x6dKFoTrmFmMYYbKNfiHZlGLKliIidd1LwmHI&m=IbjL4oi_d927aVp0WUg1u9h7LiI6yB5XUFXBVweFya0&s=s0sEeFQ4LSVD8iLdYy49VR07htOejoAVz3j85roZByA&e=" style="font-size:12.8000001907349px" target="_blank">http://chummels.org</a><br></div></div></div></div>
</div>