Python's Visualization Landscape (PyCon 2017)

Transcript

1. @jakevdp
   Jake VanderPlas
   Jake VanderPlas
   @jakevdp #PyCon2017
   Python’s Visualization
   Landscape
   

   View Slide

2. @jakevdp
   Jake VanderPlas
   [Python’s Visualization Landscape]
   From the abstract:
   “In this talk I’ll give an overview of the
   landscape of dataviz tools in Python . . .”
   

   View Slide

3. @jakevdp
   Jake VanderPlas
   [Python’s Visualization Landscape]
   From the abstract:
   “In this talk I’ll give an overview of the
   landscape of dataviz tools in Python . . .”
   

   View Slide

4. @jakevdp
   Jake VanderPlas
   From the abstract:
   “In this talk I’ll give an overview of the
   landscape of dataviz tools in Python . . .”
   [Python’s Visualization Landscape]
   

   View Slide

5. @jakevdp
   Jake VanderPlas
   From the abstract:
   “In this talk I’ll give an overview of the
   landscape of dataviz tools in Python . . .”
   [Python’s Visualization Landscape]
   

   View Slide

6. @jakevdp
   Jake VanderPlas
   From the abstract:
   “In this talk I’ll give an overview of the
   landscape of dataviz tools in Python . . .”
   [Python’s Visualization Landscape]
   

   View Slide

7. @jakevdp
   Jake VanderPlas
   From the abstract:
   “In this talk I’ll give an overview of the
   landscape of dataviz tools in Python . . .”
   [Python’s Visualization Landscape]
   

   View Slide

8. @jakevdp
   Jake VanderPlas
   From the abstract:
   “In this talk I’ll give an overview of the
   landscape of dataviz tools in Python . . .”
   [Python’s Visualization Landscape]
   

   View Slide

9. @jakevdp
   Jake VanderPlas
   From the abstract:
   “In this talk I’ll give an overview of the
   landscape of dataviz tools in Python . . .”
   [Python’s Visualization Landscape]
   From the abstract:
   “In this talk I’ll give an overview of the
   landscape of dataviz tools in Python . . .”
   

   View Slide

10. @jakevdp
    Jake VanderPlas
    [Python’s Visualization Landscape]
    From the abstract:
    “In this talk I’ll give an overview of the
    landscape of dataviz tools in Python . . .”
    

    View Slide

11. @jakevdp
    Jake VanderPlas
    [Making Sense of the Deluge]
    

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12. @jakevdp
    Jake VanderPlas
    matplotlib
    

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13. @jakevdp
    Jake VanderPlas
    matplotlib
    basemap/
    cartopy
    

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14. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    basemap/
    cartopy
    

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15. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    networkx
    basemap/
    cartopy
    

    View Slide

16. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap/
    cartopy
    

    View Slide

17. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    

    View Slide

18. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    

    View Slide

19. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    

    View Slide

20. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    bokeh
    plotly
    

    View Slide

21. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    bqplot
    bokeh
    toyplot
    plotly
    

    View Slide

22. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    ipyleaflet
    

    View Slide

23. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    ipyleaflet
    

    View Slide

24. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    ipyleaflet
    

    View Slide

25. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    d3js
    mpld3
    ipyleaflet
    

    View Slide

26. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    d3js
    mpld3
    ipyleaflet
    Vega-Lite
    Vega
    

    View Slide

27. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    d3js
    mpld3
    Altair
    Vincent
    ipyleaflet
    d3po
    Vega-Lite
    Vega
    

    View Slide

28. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    d3js
    mpld3
    Altair
    Vincent
    ipyleaflet
    d3po
    Vega-Lite
    Vega
    

    View Slide

29. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    datashader
    d3js
    mpld3
    Altair
    Vincent
    ipyleaflet
    d3po
    Vega-Lite
    Vega
    

    View Slide

30. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    datashader
    d3js
    mpld3
    Altair
    Vincent
    ipyleaflet
    d3po
    Vega-Lite
    Vega
    Vaex
    

    View Slide

31. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    holoviews
    datashader
    d3js
    mpld3
    Altair
    Vincent
    ipyleaflet
    d3po
    Vega-Lite
    Vega
    Vaex
    

    View Slide

32. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    holoviews
    datashader
    d3js
    mpld3
    Altair
    Vincent
    OpenGL
    ipyleaflet
    d3po
    Vega-Lite
    Vega
    Vaex
    

    View Slide

33. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    holoviews
    datashader
    d3js
    mpld3
    Altair
    Vincent
    OpenGL
    Glumpy
    Vispy
    ipyleaflet
    d3po
    Vega-Lite
    Vega
    Vaex
    

    View Slide

34. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    holoviews
    datashader
    d3js
    mpld3
    Altair
    Vincent
    OpenGL
    Glumpy
    Vispy
    ipyleaflet
    d3po
    Vega-Lite
    Vega
    graphviz
    Vaex
    graph-tool
    

    View Slide

35. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    holoviews
    datashader
    d3js
    mpld3
    Altair
    Vincent
    OpenGL
    Glumpy
    Vispy
    ipyleaflet
    Lightning
    GlueViz
    YT
    d3po
    Vega-Lite
    Vega
    MayaVi
    graphviz
    GR
    framework
    PyQTgraph
    pygal chaco
    Vaex
    graph-tool
    

    View Slide

36. @jakevdp
    Jake VanderPlas
    Python’s Visualization
    Landscape
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    holoviews
    datashader
    d3js
    mpld3
    Altair
    Vincent
    OpenGL
    Glumpy
    Vispy
    ipyleaflet
    Lightning
    GlueViz
    YT
    d3po
    Vega-Lite
    Vega
    MayaVi
    graphviz
    GR
    framework
    PyQTgraph
    pygal chaco
    Vaex
    graph-tool
    

    View Slide

37. @jakevdp
    Jake VanderPlas
    

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38. @jakevdp
    Jake VanderPlas
    How did we get here?
    

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39. @jakevdp
    Jake VanderPlas
    In the beginning was matplotlib*
    * well, actually… Python visualization
    existed before matplotlib, but was not
    very mature.
    

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40. @jakevdp
    Jake VanderPlas
    Plotting with Matplotlib
    Strengths:
    - Designed like MatLab: switching was easy
    

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41. @jakevdp
    Jake VanderPlas
    Plotting with Matplotlib
    Strengths:
    - Designed like MatLab: switching was easy
    - Many rendering backends
    

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42. @jakevdp
    Jake VanderPlas
    Plotting with Matplotlib
    Strengths:
    - Designed like MatLab: switching was easy
    - Many rendering backends
    - Can reproduce just about any plot (with a bit of effort)
    

    View Slide

43. @jakevdp
    Jake VanderPlas
    Plotting with Matplotlib
    Strengths:
    - Designed like MatLab: switching was easy
    - Many rendering backends
    - Can reproduce just about any plot (with a bit of effort)
    - Well-tested, standard tool for over a decade
    

    View Slide

44. @jakevdp
    Jake VanderPlas
    Matplotlib Gallery
    

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45. @jakevdp
    Jake VanderPlas
    import pandas as pd
    iris = pd.read_csv('iris.csv')
    iris.head()
    Tidy data: i.e. rows are samples, columns are features
    Example: Statistical Data
    

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46. @jakevdp
    Jake VanderPlas
    “I want to scatter petal length vs.
    sepal length, and color by species”
    Just a simple visualization . . .
    

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47. @jakevdp
    Jake VanderPlas
    color_map = dict(zip(iris.species.unique(),
    ['blue', 'green', 'red']))
    for species, group in iris.groupby('species'):
    plt.scatter(group['petalLength'], group['sepalLength'],
    color=color_map[species],
    alpha=0.3, edgecolor=None,
    label=species)
    plt.legend(frameon=True, title='species')
    plt.xlabel('petalLength')
    plt.ylabel('sepalLength')
    Just a simple visualization . . .
    

    View Slide

48. @jakevdp
    Jake VanderPlas
    Plotting with Matplotlib
    Strengths:
    - Designed like MatLab: switching was easy
    - Many rendering backends
    - Can reproduce just about any plot with a bit of
    effort
    - Well-tested, standard tool for over a decade
    Weaknesses:
    - API is imperative & often overly verbose
    - Sometimes poor stylistic defaults
    - Poor support for web/interactive graphs
    - Often slow for large & complicated data
    

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49. @jakevdp
    Jake VanderPlas
    Everyone’s Goal:
    Improve on the weaknesses of matplotlib
    (without sacrificing the strengths!)
    

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50. @jakevdp
    Jake VanderPlas
    Building on Matplotlib. . .
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    

    View Slide

51. @jakevdp
    Jake VanderPlas
    Building on Matplotlib. . .
    Common Idea: Keep matplotlib as a versatile,
    well-tested backend, and provide a new
    domain-specific API.
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    

    View Slide

52. @jakevdp
    Jake VanderPlas
    Building on Matplotlib. . .
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    

    View Slide

53. @jakevdp
    Jake VanderPlas
    Pandas plotting API
    Key Features:
    - Pandas provides a DataFrame object
    - Also provides a simple API for plotting DataFrames
    

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54. @jakevdp
    Jake VanderPlas
    iris.plot.scatter('petalLength', 'petalWidth')
    

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55. @jakevdp
    Jake VanderPlas
    from pandas.tools.plotting import andrews_curves
    andrews_curves(iris, 'species')
    - More sophisticated statistical visualization tools have
    recently been added
    

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56. @jakevdp
    Jake VanderPlas
    http://seaborn.pydata.org
    Key Features:
    - Like Pandas, wraps matplotlib
    - Nice set of color palettes & plot styles
    - Focus on statistical visualization & modeling
    Seaborn: statistical data visualization
    

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57. @jakevdp
    Jake VanderPlas
    import seaborn as sns
    sns.lmplot('petalLength', 'sepalWidth', iris,
    hue='species', fit_reg=False)
    Seaborn examples
    

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58. @jakevdp
    Jake VanderPlas
    sns.pairplot(iris, hue='species')
    Seaborn examples
    

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59. @jakevdp
    Jake VanderPlas
    Javascript-based Viz:
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    ipyleaflet
    

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60. @jakevdp
    Jake VanderPlas
    Javascript-based Viz:
    Common Idea: build a new API that produces a plot
    serialization (often JSON) that can be displayed in the
    browser (often in Jupyter notebooks)
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    ipyleaflet
    

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61. @jakevdp
    Jake VanderPlas
    Javascript-based Viz:
    javascript
    pythreejs
    bqplot
    toyplot
    ipyvolume
    cufflinks
    ipyleaflet
    bokeh
    plotly
    

    View Slide

62. @jakevdp
    Jake VanderPlas
    Plotting with Bokeh
    

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63. @jakevdp
    Jake VanderPlas
    Bokeh Gallery
    

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64. @jakevdp
    Jake VanderPlas
    Plotting with Bokeh
    Advantages:
    - Web view/interactivity
    - Imperative and Declarative layer
    - Handles large and/or streaming datasets
    - Geographical visualization
    - Fully open source
    Disadvantages:
    - No vector output (need PDF/EPS? Sorry)
    - Newer tool with a smaller user-base than
    matplotlib
    

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65. @jakevdp
    Jake VanderPlas
    Basic Plotting with Plotly
    

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66. @jakevdp
    Jake VanderPlas
    Plotly Gallery
    

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67. @jakevdp
    Jake VanderPlas
    Plotting with Plotly
    Advantages:
    - Web view/interactivity
    - Multi-language support
    - 3D plotting capability
    - Animation capability
    - Geographical visualization
    Disadvantages:
    - Some features require a paid plan
    

    View Slide

68. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    holoviews
    datashader
    d3js
    mpld3
    Altair
    Vincent
    OpenGL
    Glumpy
    Vispy
    ipyleaflet
    Lightning
    GlueViz
    YT
    d3po
    Vega-Lite
    Vega
    MayaVi
    graphviz
    GR
    framework
    PyQTgraph
    pygal chaco
    Vaex
    graph-tool
    Visualization for Larger Data . . .
    

    View Slide

69. @jakevdp
    Jake VanderPlas
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    holoviews
    d3js
    mpld3
    Altair
    Vincent
    OpenGL
    Glumpy
    Vispy
    ipyleaflet
    Lightning
    GlueViz
    YT
    d3po
    Vega-Lite
    Vega
    MayaVi
    graphviz
    GR
    framework
    PyQTgraph
    pygal chaco
    Vaex
    graph-tool
    Visualization for Larger Data . . .
    datashader
    

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70. @jakevdp
    Jake VanderPlas
    Datashader
    Fast server-side engine for dynamic data aggregation
    

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71. @jakevdp
    Jake VanderPlas
    Datashader
    - Compute layer that works with Bokeh
    - Rather than sending data to the client, it aggregates
    data and sends pixels.
    - Can handle interactive visualization of billions of rows.
    

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72. @jakevdp
    Jake VanderPlas
    Datashader
    - Compute layer that works with Bokeh
    - Rather than sending data to the client, it aggregates
    data and sends pixels.
    - Can handle interactive visualization of billions of rows.
    

    View Slide

73. @jakevdp
    Jake VanderPlas
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    pythreejs
    bqplot
    toyplot
    plotly
    ipyvolume
    cufflinks
    holoviews
    datashader
    mpld3
    Vincent
    OpenGL
    Glumpy
    Vispy
    ipyleaflet
    Lightning
    GlueViz
    YT
    d3po
    Vega-Lite
    Vega
    MayaVi
    graphviz
    GR
    framework
    PyQTgraph
    pygal chaco
    Vaex
    graph-tool
    Toward Declarative Visualization . . .
    d3js
    javascript
    bokeh
    matplotlib
    Altair
    

    View Slide

74. @jakevdp
    Jake VanderPlas
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    pythreejs
    bqplot
    toyplot
    plotly
    ipyvolume
    cufflinks
    holoviews
    mpld3
    Vincent
    OpenGL
    Glumpy
    Vispy
    ipyleaflet
    Lightning
    GlueViz
    YT
    d3po
    Vega-Lite
    Vega
    MayaVi
    graphviz
    GR
    framework
    PyQTgraph
    pygal chaco
    Vaex
    graph-tool
    Toward Declarative Visualization . . .
    d3js
    javascript
    bokeh
    matplotlib
    Altair
    datashader
    

    View Slide

75. @jakevdp
    Jake VanderPlas
    Holoviews
    - Datasets themselves stored in objects that
    automatically produce intelligent visualizations
    - Composition & Interactivity via operator overloading
    - Renders to Bokeh, DataShader, and Matplotlib
    

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76. @jakevdp
    Jake VanderPlas
    Holoviews
    - Also can handle geographic data & time-series
    

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77. @jakevdp
    Jake VanderPlas
    What if instead of passing
    around pixels, we pass around
    visualization specifications plus data?
    Altair
    

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78. @jakevdp
    Jake VanderPlas
    What if instead of passing
    around pixels, we pass around
    visualization specifications plus data?
    “Declarative Visualization”
    Altair
    

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79. @jakevdp
    Jake VanderPlas
    What if instead of passing
    around pixels, we pass around
    visualization specifications plus data?
    “Declarative Visualization”
    Altair
    

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80. @jakevdp
    Jake VanderPlas
    Declarative Visualization:
    Viz for data science
    Declarative
    - Specify What should be
    done
    - Details determined
    automatically
    - Separates Specification
    from Execution
    Imperative
    - Specify How something
    should be done.
    - Must manually specify
    plotting steps
    - Specification &
    Execution intertwined.
    Declarative visualization lets you think about data
    and relationships, rather than incidental details.
    

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81. #JSM2016
    Jake VanderPlas
    From D3 to Altair . . .
    (link to live version)
    

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82. #JSM2016
    Jake VanderPlas
    But working in D3 can
    be challenging . . .
    

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83. #JSM2016
    Jake VanderPlas
    Bar Chart: d3
    var margin = {top: 20, right: 20, bottom: 30, left: 40},
    width = 960 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;
    var x = d3.scale.ordinal()
    .rangeRoundBands([0, width], .1);
    var y = d3.scale.linear()
    .range([height, 0]);
    var xAxis = d3.svg.axis()
    .scale(x)
    .orient("bottom");
    var yAxis = d3.svg.axis()
    .scale(y)
    .orient("left")
    .ticks(10, "%");
    var svg = d3.select("body").append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
    .append("g")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")");
    d3.tsv("data.tsv", type, function(error, data) {
    if (error) throw error;
    x.domain(data.map(function(d) { return d.letter; }));
    y.domain([0, d3.max(data, function(d) { return d.frequency; })]);
    svg.append("g")
    .attr("class", "x axis")
    .attr("transform", "translate(0," + height + ")")
    .call(xAxis);
    svg.append("g")
    .attr("class", "y axis")
    .call(yAxis)
    .append("text")
    .attr("transform", "rotate(-90)")
    .attr("y", 6)
    .attr("dy", ".71em")
    .style("text-anchor", "end")
    .text("Frequency");
    svg.selectAll(".bar")
    .data(data)
    .enter().append("rect")
    .attr("class", "bar")
    .attr("x", function(d) { return x(d.letter); })
    .attr("width", x.rangeBand())
    .attr("y", function(d) { return y(d.frequency); })
    .attr("height", function(d) { return height - y(d.frequency); });
    });
    function type(d) {
    d.frequency = +d.frequency;
    return d;
    }
    D3 is a Javascript package that
    streamlines manipulation of
    objects on a webpage.
    

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84. #JSM2016
    Jake VanderPlas
    Bar Chart: Vega
    {
    "width": 400,
    "height": 200,
    "padding": {"top": 10, "left": 30, "bottom": 30, "right": 10},
    "data": [
    {
    "name": "table",
    "values": [
    {"x": 1, "y": 28}, {"x": 2, "y": 55},
    {"x": 3, "y": 43}, {"x": 4, "y": 91},
    {"x": 5, "y": 81}, {"x": 6, "y": 53},
    {"x": 7, "y": 19}, {"x": 8, "y": 87},
    {"x": 9, "y": 52}, {"x": 10, "y": 48},
    {"x": 11, "y": 24}, {"x": 12, "y": 49},
    {"x": 13, "y": 87}, {"x": 14, "y": 66},
    {"x": 15, "y": 17}, {"x": 16, "y": 27},
    {"x": 17, "y": 68}, {"x": 18, "y": 16},
    {"x": 19, "y": 49}, {"x": 20, "y": 15}
    ]
    }
    ],
    "scales": [
    {
    "name": "x",
    "type": "ordinal",
    "range": "width",
    "domain": {"data": "table", "field": "x"}
    },
    {
    "name": "y",
    "type": "linear",
    "range": "height",
    "domain": {"data": "table", "field": "y"},
    "nice": true
    }
    ],
    "axes": [
    {"type": "x", "scale": "x"},
    {"type": "y", "scale": "y"}
    ],
    "marks": [
    {
    "type": "rect",
    "from": {"data": "table"},
    "properties": {
    "enter": {
    "x": {"scale": "x", "field": "x"},
    "width": {"scale": "x", "band": true, "offset": -1},
    "y": {"scale": "y", "field": "y"},
    "y2": {"scale": "y", "value": 0}
    },
    "update": {
    "fill": {"value": "steelblue"}
    Vega is a detailed declarative
    specification for visualizations,
    built on D3.
    

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85. #JSM2016
    Jake VanderPlas
    Bar Chart: Vega-Lite
    {
    "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"}
    }
    }
    Vega-Lite is a simpler
    declarative specification aimed
    at statistical visualization.
    

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86. #JSM2016
    Jake VanderPlas
    Bar Chart: Altair
    Altair is a Python API for creating
    Vega-Lite specifications.
    

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87. @jakevdp
    Jake VanderPlas
    From Declarative API
    to declarative Grammar
    chart = Chart(data).mark_circle(
    opacity=0.3
    ).encode(
    x='petalLength:Q',
    y='sepalWidth:Q',
    color='species:N',
    )
    chart.display()
    

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88. @jakevdp
    Jake VanderPlas
    From Declarative API
    to declarative Grammar
    >>> chart.to_dict()
    {'config': {'mark': {'opacity': 0.3}},
    'data':
    {'url': 'https://vega.github.io/vega-datasets/data/iris.json'},
    'encoding': {'color': {'field': 'species', 'type': 'nominal'},
    'x': {'field': 'petalLength', 'type': 'quantitative'},
    'y': {'field': 'sepalWidth', 'type': 'quantitative'}},
    'mark': 'circle'}
    

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89. #JSM2016
    Jake VanderPlas
    (Visualizations from
    jakevdp/altair-examples).
    

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90. #JSM2016
    Jake VanderPlas
    Coming Very Soon: Altair 2.0
    - Includes a Grammar of Interaction
    

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91. @jakevdp
    Jake VanderPlas
    or
    $ conda install altair --channel conda-forge
    $ pip install altair
    $ jupyter nbextension install --sys-prefix --py vega
    Try Altair:
    http://github.com/ellisonbg/altair/
    For a Jupyter notebook tutorial, type
    import altair
    altair.tutorial()
    

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92. @jakevdp
    Jake VanderPlas
    Python’s Visualization
    Landscape
    matplotlib
    seaborn
    pandas
    ggpy
    scikit-
    plot
    Yellow
    brick
    networkx
    basemap
    /cartopy
    javascript
    pythreejs
    bqplot
    bokeh
    toyplot
    plotly
    ipyvolume
    cufflinks
    holoviews
    datashader
    d3js
    mpld3
    Altair
    Vincent
    OpenGL
    Glumpy
    Vispy
    ipyleaflet
    Lightning
    GlueViz
    YT
    d3po
    Vega-Lite
    Vega
    MayaVi
    graphviz
    GR
    framework
    PyQTgraph
    pygal chaco
    Vaex
    graph-tool
    

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93. @jakevdp
    Jake VanderPlas
    Email: [email protected]
    Twitter: @jakevdp
    Github: jakevdp
    Web: http://vanderplas.com/
    Blog: http://jakevdp.github.io/
    Thank You!
    

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