gvisMotionChart: Google Motion Chart with R

Description

The gvisMotionChart function reads a data.frame and creates text output referring to the Google Visualisation API which can be included into a web page, or as a stand-alone page. The actual chart is rendered by the web browser in flash.

A Motion Chart is a dynamic chart to explore several indicators over time.

Usage

gvisMotionChart(data, idvar = "id", timevar = "time", 
		      date.format = "%Y/%m/%d", 
		      options = list(), chartid)

Arguments

data

a data.frame. The data has to have at least four columns with subject name (idvar), time (timevar) and two columns of numeric values. Further columns, numeric and character/factor are optional. The combin

idvar

column name of data with the subject to be analysed.

timevar

column name of data which shows the time dimension. The information has to be either numeric or of class Date.

date.format

if timevar is of class Date then this argument specifies how the dates are reformatted to be used by JavaScript.

options

list of configuration options for Google Motion Chart. The possible components are, taken from http://code.google.com/apis/visualization/documentation/gallery/motionchart.html#Configuration_Options: [object Object],[object Object],

chartid

character. If missing (default) a random chart id will be generated based on chart type and tempfile

Value

gvisMotionChart returns list of class "gvis" and "list". An object of class "gvis" is a list containing at least the following components:
typeGoogle visualisation type, here 'MotionChart'
chartidcharacter id of the chart object. Unique chart ids are required to place several charts on the same page.
htmla list with the building blocks for a page [object Object],[object Object],[object Object],[object Object]

References

Google Motion Chart API: http://code.google.com/apis/visualization/documentation/gallery/motionchart.html

Follow the link for Google's data policy.

In 2006 Hans Rosling gave an inspiring talk at TED http://www.ted.com/talks/hans_rosling_shows_the_best_stats_you_ve_ever_seen.html about social and economic developments in the world over the last 50 years, which challenged the views and perceptions of many listeners. Rosling had used extensive data analysis to reach his conclusions. To visualise his talk, he and his team at Gapminder http://www.gapminder.org had developed animated bubble charts, aka motion charts.

In March 2007 Google acquired Trendalyzer from the Gapminder Foundation and the Gapminder team of developers joined Google in California in April 2007. Yihui Xie, the maintainer of the animation-package showed in an early blog entry the usage of the Google Motion Chart API with R:

http://yihui.name/en/2008/11/brownian-motion-using-google-visualization-api-and-r/ Further examples of displaying data with motion charts are available via the Google Public Data Explorer: http://www.google.com/publicdata/home.

Stephen Thompson at Lloyd's developed an Excel version that mimics much of the functionality of the Google motion charts: http://www.lloyds.com/The-Market/Tools-and-Resources/Resources/Statistics-Relating-to-Lloyds/Visualisation

Examples

Run this code

## Please note that by default the googleVis plot command
## will open a browser window and requires Flash and Internet
## connection to display the visualisation.

Fruits	
## timevar Year
M1 <- gvisMotionChart(Fruits, idvar="Fruit", timevar="Year")
str(M1)
## print.gvis, will concatenate the list into a one long string
M1

plot(M1)

## Combine with another chart, e.g. table
tbl <- gvisTable(Fruits, options=list(height=220))
Mtbl <- gvisMerge(M1, tbl)
plot(Mtbl)

## Usage of date variable
M2 <- gvisMotionChart(Fruits, idvar="Fruit", timevar="Date",
                               date.format = "%Y%m%d") 
plot(M2)
## Options: no side panel on the right
M3 <- gvisMotionChart(Fruits,"Fruit","Year",
                 options=list(showSidePanel=FALSE))
plot(M3)
## Options: trails un-ticked
M4 <- gvisMotionChart(Fruits, "Fruit", "Year",
                 options=list(state='{"showTrails":false};'))

plot(M4)

## Using information from the advanced state settings
##
## In the browser window you can change some of displaying settings,
## e.g. the level of opacity of not selected items.
## Copy and paste the state string from the 'Advanced' tab into R
## and you can add it to your list of options:

myStateSettings <-'
{"xZoomedDataMax":111,"dimensions":{"iconDimensions":["dim0"]},
"colorOption":"2","xZoomedIn":false,"yZoomedDataMax":91,
"sizeOption":"5","yZoomedIn":false,"xLambda":1,"time":"2008",
"yZoomedDataMin":71,"iconType":"BUBBLE","showTrails":true,
"xAxisOption":"3","duration":{"timeUnit":"Y","multiplier":1},
"playDuration":15000,"nonSelectedAlpha":0,"iconKeySettings":[],
"orderedByY":false,"uniColorForNonSelected":false,"orderedByX":false,
"xZoomedDataMin":81,"yLambda":1,"yAxisOption":"4"}
'

M5 <- gvisMotionChart(Fruits, "Fruit", "Year", options=list(state=myStateSettings))
plot(M5)
## For more information see:
## http://code.google.com/apis/chart/interactive/docs/gallery/motionchart.html#Motion_Chart_initial_state