Guide.shapekey

[Mattriks]

• I've updated the documentation to reflect these changes
• I've added an entry to NEWS.md
• I've added and/or updated the unit tests
• I've run the regression tests
• I've squash'ed or fixup'ed junk commits with git-rebase
• I've built the docs and confirmed these changes don't cause new errors

Guide-ageddon

This is the first step in Guide-ageddon (and closes #1133). This PR implements:

• Guide.shapekey(title=, labels=, pos=)
• which generates a colored ShapeKey if shape and color are mapped to the same variable name.
• Theme(key_swatch_color=), useful if shape and color are mapped to different variables.

srand(123)
theme1 = Theme(point_size=3mm)
coord1 = Coord.cartesian(xmin=0.0, xmax=6.0)
D = DataFrame(x=1:5, y=rand(5), V1=["A","A","B","B","D"], V2 = string.([1,2,2,3,3])  )

pa = plot(x=1:5, y=[0.77, 0.94, 0.67, 0.39, 0.31], shape=["A","A","B","B","D"], theme1, coord1,
    Guide.shapekey(title="Key",labels=["α","β","δ"]),
    Guide.title("Guide.shapekey") )

# if shape==color, and you change levels, there are possible ways to auto-update the levels in Scale.color_discrete
# but for now, you have to do it manually:
pb = plot(D, x=:x, y=:y, shape=:V1, color=:V1,
        Scale.shape_discrete(levels=["D","A","B"]),     
        Scale.color_discrete(levels=["D","A","B"]), 
        theme1, coord1, Guide.title("Shape==Color") )

pc = plot(D, x=:x, y=:y, shape=:V1, color=:V2,  coord1,
        Guide.colorkey(title="Color", pos=[0.75w,-0.25h]),
        Guide.shapekey(title="Shape "),
        Theme(point_size=3mm, key_swatch_color="slategrey"),
        Guide.title("Shape!=Color")
        )
hstack(pa,pb,pc)

To do in this PR:

• Investigate auto-updating Scale.color_discrete, if shape==color, and you change Guide.shapekey(levels=) (as in plot b above)

Future PRs (in no particular order):

• Currently, if you have two keys (e.g. shape and color) positioned outside the plot (left or right) they will stack horizontally not vertically. I leave vertical stacking of left or right keys (and horizontal stacking of top or bottom-positioned keys) to a separate PR.
• Update Guide.colorkey
• Guide.sizekey, Guide.linekey
• Update and replace Guide.manual_color_key with Guide.manual_key

[codecov-io]

Codecov Report

Merging #1156 into master will increase coverage by 0.31%.
The diff coverage is 86.92%.

@@            Coverage Diff             @@
##           master    #1156      +/-   ##
==========================================
+ Coverage   87.06%   87.37%   +0.31%     
==========================================
  Files          33       36       +3     
  Lines        3981     4063      +82     
==========================================
+ Hits         3466     3550      +84     
+ Misses        515      513       -2

Impacted Files	Coverage Δ
src/aesthetics.jl	82.35% <ø> (ø)	⬆️
src/guide.jl	100% <ø> (+14.07%)	⬆️
src/theme.jl	67.3% <ø> (ø)	⬆️
src/guide/misc.jl	100% <100%> (ø)
src/Gadfly.jl	79.42% <100%> (+1.7%)	⬆️
src/guide/plot.jl	85.02% <85.02%> (ø)
src/guide/keys.jl	86.52% <86.52%> (ø)
src/statistics.jl	93.52% <0%> (-0.02%)	⬇️
... and 25 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update f922f4d...071831f. Read the comment docs.

[bjarthur]

this will be great to have. any thoughts on legends for size_{continuous,discrete}?

[Mattriks]

See list of Future PRs above - Guide.sizekey is there. I think a sizekey should be easy, because even when the size variable is continuous, the key still contains discrete-size circles.

Note that I'm planning to make all discrete keys use render_discrete_key (new in this PR), which will contain keywords args for color, shape, size. If the keyword arg is not provided, then the relevant default from Theme is used.

[bjarthur]

@Mattriks #1116 is ready to merge. but there will be lots of conflicts with this PR regarding your splitting of guides.jl. i think it would be best to do that in a separate PR.

also, if you think you'll be ready to merge this PR soon, i could wait to merge mine until afterwards. could work on seaborn-style thumbnails in the meantime. let me know.

[Mattriks]

Rebased on master. The tests all pass locally for me.
Now that I've rebased, I can make the shapekey documentation consistent with the new "gallery format".

[bjarthur]

lgtm except reformatting the docs to the new "gallery format". let's get this merged before 0.7!

[Mattriks]

I've updated the docs now, and ran the regression tests. There are diffs in any testfile that is prefixed "point_shape" or "point_*_shape" i.e. a shape key is added as expected. Tests passed for Julia 0.6 on Travis.

[bjarthur]

thanks! looking forward to "Future PRs" you list in the OP.

[bjarthur]

if the length of the shape aesthetic is one would it make sense to not show the shape key? see http://gadflyjl.org/latest/gallery/shapes.html

[Mattriks]

Yes, I'll have to fix that, so it is consistent with the behaviour of the color aesthetic, e.g. color=[colorant"orange"]

[bjarthur]

@Mattriks what's the best way to fix the shape legend appearing when the length of shape is just one? i'm going to either have to fix it or change all my scripts, so figure i might as well tackle this.

[Mattriks]

Either:

• let me finish Fixes #1126 #1175 without the deprecation, or
• show me a way of doing a Theme field deprecation which works,
  and I'll get back to the above shape issue. 🙂

I also started working on Guide.linekey, so I'm thinking about a holistic solution when the aesthetic length is one.

[bjarthur]

great to hear about linekey!

ideally it'd be best if we could fix this regression and tag a new point release before introducing any breaking changes like that in #1175.

[tlnagy]

I agree with @bjarthur here. I think lets fix this regression first and tag a new point release, merge #1175 and company and push one last feature release before we drop support for 0.6 on master.

[bjarthur]

@Mattriks any chance you'll have time in the near future to get the shape legend to not appear when the length of the shape aesthetic is just one? would be nice to get this fixed before we drop support for julia 0.6. thanks.