rendering vega-lite specs

[keesterbrugge]

Hi,

Thanks for your work on this kernel.

Currently I mostly use ggplot in R for visualisations. I would love to have vega-lite available to me in a notebook environment with clojure.

In the ipython kernel a vega-lite spec can be rendered inline as follows

from IPython.display import display

display({
    "application/vnd.vegalite.v2+json": {
        "$schema": "https://vega.github.io/schema/vega-lite/v2.json",
        "description": "A simple bar chart with embedded data.",
        "data": {
            "values": [
                {"a": "A", "b": 28}, {"a": "B", "b": 55}, {"a": "C", "b": 43},
                {"a": "D", "b": 91}, {"a": "E", "b": 81}, {"a": "F", "b": 53},
                {"a": "G", "b": 19}, {"a": "H", "b": 87}, {"a": "I", "b": 52}
            ]
        },
        "mark": "bar",
        "encoding": {
            "x": {"field": "a", "type": "ordinal"},
            "y": {"field": "b", "type": "quantitative"}
        }
    }
}, raw=True)

Does similar functionality exist in iClojure?

[cgrand]

#unrepl/mime {:content-type "application/vnd.vegalite.v2+json" :content {
        "$schema" "https://vega.github.io/schema/vega-lite/v2.json",
        "description" "A simple bar chart with embedded data.",
        "data" {
            "values" [
                {"a" "A", "b" 28}, {"a" "B", "b" 55}, {"a" "C", "b" 43},
                {"a" "D", "b" 91}, {"a" "E", "b" 81}, {"a" "F", "b" 53},
                {"a" "G", "b" 19}, {"a" "H", "b" 87}, {"a" "I", "b" 52}
            ]
        },
        "mark" "bar",
        "encoding" {
            "x" {"field" "a", "type" "ordinal"},
            "y" {"field" "b", "type" "quantitative"}
        }}}

should work

[keesterbrugge]

Hi Christophe,

Thanks! This indeed works, see the screenshot below.

However, if I want to use a vega-lite spec that's bound to a symbol – vl-spec in this case – I don't know how to use #unrepl/mime anymore

and if I want to plot the result of a function call it seems to turn into an infinite loop

Is this expected behaviour?

I would like to be able to create my vega-lite specs with a library like oz and/or read in json files and then plot them inline with unrepl/mime

I would appreciate suggestions on how to do that.

Thanks again for your work!

[cgrand]

Actually you are breaking grounds. Let's me explain how it works right now:

1. If the returned value is a #unrepl/mime tag literal then the payload goes through the MIME facilities of Jupyter Lab
2. tag literals are literals, not expressions, so lists (or symbols) inside them are not evaluated
3. up to earlier today there was a bug with "long" (10-ish) lists, it has been fixed on master.

The workaround for 2/ is to do (tagged-literal 'unrepl/mime (my-spec)) but I'm considering evaluating expressions inside literals.

Does it shed enough light on the matter to help you solve the issue?

[keesterbrugge]

Thank for you fast response.

I can confirm this now works

This helps a lot

[metasoarous]

@cgrand Thanks for unblocking us! Would vega work more or less the same way with s/vegalite/vega/ applied to the :content-type? Also, I'm assuming v2 is for version here; Do you know if its possible to get a RC version through this :content-type specification?

Thanks again!

[cgrand]

@metasoarous honestly I have no idea. IClojure does nothing special (except edn -> json conversion) so whatever works with IPython.display should work with unrepl/mime.

[cgrand]

@keesterbrugge with the commit above your original code should work (without explicit tagged-literal call)

[keesterbrugge]

You're right

Cheers!