Creating accessible tables and graphs with R

########################################
#Load libraries.
library(xtable) #for tables
library(R2HTML) #for graphs
library(datasets) #for data
########################################
#Initiate a HTML file to export results.
#The file can be named with a DOC extension to facilitate opening it with Word.
name.file.htm <- "Accessible Tables and Graphs.doc"
HTML.title(
"Add alternative titles and descriptions to tables and graphs in a HTML-based DOC file",
file = name.file.htm, HR = 1, append = F)
########################################
#Accessible table example
#Assign alternative title and description to a single object.
html.table.attributes <- paste('border=1',
'title="Table of days of frost and years of life expectancy"',
'summary="Table of days of frost and years of life expectancy"')
#The xtable(caption) argument places the title in the first row of the table, making it
#more difficult to designate table headers to repeat across multiple pages in a document.
#Produce the table title with HTML.title() instead.
HTML.title("Days of frost and years of life expectancy", file = name.file.htm, HR = 3)
#Create table and write to file.
data.frost.exp <- as.data.frame(state.x77[, c("Frost", "Life Exp")])
names(data.frost.exp)[2] <- "Life"
table.xtable <- xtable(data.frost.exp, digits = c(NA, 0, 2))
print(table.xtable, type = "html", html.table.attributes = html.table.attributes,
file = name.file.htm, border = 1, append = T)
HTML("<br>", file = name.file.htm)
########################################
#Accessible graph example
#Modify HTMLInsertGraph() by adding Title and Alt arguments.
HTMLInsertGraph <- function (GraphFileName = "", Caption = "",
Title = "untitled graph", Alt = "a graph",
GraphBorder = 1, Align = "center",
WidthHTML = 500, HeightHTML = NULL,
file = get(".HTML.file"), append = TRUE, ...) {
cat("n", file = file, append = append, ...)
cat(paste("<p align=", Align, "><img src='", GraphFileName,
"' title='", Title, "' alt='", Alt, "' border=", GraphBorder,
if (!is.null(WidthHTML))
paste(" width=", WidthHTML, sep = "")
else "",
if (!is.null(HeightHTML))
paste(" height=", HeightHTML, sep = "")
else "", ">", sep = "", collapse = ""),
file = file, append = TRUE, sep = "")
if (Caption != "")
cat(paste("<br><i class=caption>", Caption, "</i>"),
file = file, append = TRUE, sep = "")
invisible(return(TRUE))
}
#Assign alternative title and description to objects.
Title <- "Graph of days of frost and years of life expectancy"
Alt <- "Graph of days of frost and years of life expectancy"
name.file.plot <- "Days of frost and years of life expectancy.png"
png(name.file.plot, width = 350, height = 350)
plot(data.frost.exp, main = "Days of frost and years of life expectancy", family = "serif")
abline(lm(Life ~ Frost, data.frost.exp), col = "red")
dev.off()
HTMLInsertGraph(GraphFileName = name.file.plot, file = name.file.htm, Align = "left",
WidthHTML = 350, HeightHTML = 350, append = T, Title = Title, Alt = Alt)
HTML("<br>", file = name.file.htm)