googleVis (version 0.7.1)

gvisBarChart: Google Bar Chart with R googleChartName <- "barchart" gvisChartName <- "gvisBarChart"

Description

The gvisBarChart 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 using SVG or VML.

Usage

gvisBarChart(data, xvar = "", yvar = "", options = list(), chartid)

Value

paste(gvisChartName) returns list of class

paste(readLines(file.path(".", "inst", "mansections", "gvisOutputStructure.txt")))

Arguments

data

a data.frame to be displayed as a bar chart

xvar

name of the character column which contains the category labels for the x-axes.

yvar

a vector of column names of the numerical variables to be plotted. Each column is displayed as a separate bar/column.

options

list of configuration options, see:

gsub("CHARTNAME", googleChartName, readLines(file.path(".", "inst", "mansections", "GoogleChartToolsURLConfigOptions.txt")))

paste(readLines(file.path(".", "inst", "mansections", "gvisOptions.txt")))

chartid

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

Author

Markus Gesmann ,

Diego de Castillo

References

Google Chart Tools API: gsub("CHARTNAME", googleChartName, readLines(file.path(".", "inst", "mansections", "GoogleChartToolsURL.txt")))

See Also

See also print.gvis, plot.gvis for printing and plotting methods

Examples

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

df <- data.frame(country=c("US", "GB", "BR"), 
                           val1=c(1,3,4), 
                           val2=c(23,12,32))

## Bar chart
Bar1 <- gvisBarChart(df, xvar="country", yvar=c("val1", "val2"))
plot(Bar1)

## Stacked bar chart
Bar2 <- gvisBarChart(df, xvar="country", yvar=c("val1", "val2"),
     options=list(isStacked=TRUE))
plot(Bar2)


## Add a customised title and change width of bars
Bar3 <- gvisBarChart(df, xvar="country", yvar=c("val1", "val2"),
             options=list(title="Hello World",
                          titleTextStyle="{color:'red',fontName:'Courier',fontSize:16}",
                          bar="{groupWidth:'100%'}"))
plot(Bar3)

if (FALSE) {
## Change x-axis to percentages
Bar4 <- gvisBarChart(df, xvar="country", yvar=c("val1", "val2"),
                       options=list(hAxis="{format:'#,###%'}"))
plot(Bar4)

## The following example reads data from a Wikipedia table and displays
## the information in a bar chart.
## We use the readHMLTable function of the XML package to get the data
library(XML)
## Get the data of the biggest ISO container companies from Wikipedia
##(table 3):
df=readHTMLTable(readLines("https://en.wikipedia.org/wiki/Intermodal_freight_transport"))[[3]][,1:2]
## Rename the second column
names(df)[2]="TEU capacity"
## The numbers are displayed with commas to separate thousands, so let's
## get rid of them:
df[,2]=as.numeric(gsub(",", "", as.character(df[,2])))

## Finally we can create a nice bar chart:
Bar5 <- gvisBarChart(df, options=list(
                    chartArea="{left:250,top:50,width:\"50%\",height:\"75%\"}",
                    legend="bottom", 
                    title="Top 20 container shipping companies in order of TEU capacity"))

plot(Bar5)

}