An implementation of the grammar of graphics: ggplot

An implementation of the grammar of graphics: ggplot

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  An implementation ofthe grammar of graphics: ggplot* An R package by Hadley Wickham Presented by Mehran Karimzadeh *By ggplot we mean ggplot2. ggplot is deprecated
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  The world withoutggplot R base graphics: ● Manual iteration for overplotting or facetting ● Manual selection of aesthetics ● Complex manual legends ● Hard to share or reuse ● ...
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  The grammar ofgraphics Introduced by Leland Wilkinson in 1999 Essentially based on object oriented graphic objects that inherit properties of each other New graphic objects can be added to an existing functional plotting object to alter aesthetics, add features, etc.
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  Graphic objects Each graphicobject must inherit or be assigned with several parameters: ● x/y-axis value ● aesthetics: colour/fill/etc. Various graphical objects exist: ● geom: adding points/lines/bars/shapes/texts ● stat: control representation of data; often transformation ● scale: manual control of aesthetics ● coord: control coordinate system ● facet: Setting multipanel representation of data ● ...
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  Advantages of usingggplot ● No iteration for facetting or overplotting ● No need for specifying aesthetic features ● Can be reused efficiently for exploratory analysis ● Easy but extensive control over details of graphics ● Portable and dynamic
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  Example
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  Example (script)
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  Syntax; Exploration ● Toexplore distribution/frequency/etc., each row of the dataframe must have one entry of the measure you are interested; ● Here, you can explore carat in relation to cut, color or clarity, but you cannot compare distribution of carat versus depth or price. ● geoms: geom_histogram(), geom_density(), geom_boxplot(), geom_violin(), etc.
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  Most useful objects Visuals:points, lines, bars, tiles, segments, polygon, text Features: multi facetting, scaling, transforming, coordinate systems, themes
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  Add ons ● Networkvisualization (geom_net, etc.) ● ggthemes package ● plotly ● ggvis
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  Interactive ggplot withplotly ● Free for public use ● Makes your R/ggplot/matlab/python plots interactive
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  And now forsomething completely different: ggplot; Brought to you in python
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  ggplot in python
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  Only with minimalfunctionality Many features not yet available: ● Positioned bar plots ● boxplot ● facet_grid ● etc. For contribution: https://github.com/yhat/ggplot/blob/master/TODO.md
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  Questions?