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All 4 books by Edward Tufte now in
paperback editions, $100 for all 4
Visual Display of Quantitative Information
Envisioning Information
Visual Explanations
Beautiful Evidence
Paper/printing = original clothbound books.
Only available through ET's Graphics Press:
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Edward Tufte e-books
Immediate download to any computer
connected to the internet:
La Representación Visual de Información
Cuantitativa, (200 páginas) $12
Visual and Statistical Thinking, $2
The Cognitive Style of Powerpoint, $2
Seeing Around + Feynman Diagrams, $2
Data Analysis for Politics and Policy, $2
catalog + shopping cart
Edward Tufte one-day course,
Presenting Data and Information
Portland, August 4
Seattle, August 5, 6, 7
Denver, August 11
San Jose, December 15
San Francisco, December 18, 19
Response to Sparklines: computer code implementation

Here is a simple R implementation of sparklines. Running sparkline() will generate a random sparkline; running sparkline(yourdata) will generate a sparkline using the data in yourdata. As an example, here is Google's stock price for the last year.

#R sparklines
sparkline<-function(ydata=rnorm(100,500,50),width=1.5,height=0.5,sigfigs=4) {

# ydata = vector of data to be plotted
# width = width of sparlkline in inches, including text
# height = height of sparkline in inches
# sigfigs = number of significant figures to round min, max, and last values to

	temppar<-par(no.readonly = TRUE) # store default graphics parameters
	par(mai=c(0.10,0.05,0.10,0.05),fin=c(width,height)) # adjust graphics parameters for sparklines
	len<-length(ydata) # determine the length of the data set
	ymin<-min(ydata) # determine the minimum
	tmin<-which.min(ydata) # and its index
	ymax<-max(ydata) # determine the maximum
	tmax<-which.max(ydata) # and its index
	yfin<-signif(ydata[len],sigfigs) #determine most recent data point
	plotrange=c(ymin-0.3*(ymax-ymin),ymax+0.3*(ymax-ymin)) # define plot range to leave enough room for min and max circles and text
	plot(x=1:len,y=ydata,type="l",xlim=c(1,len*1.5),ylim=plotrange,col="gray",lwd=0.5,ann=FALSE,axes=FALSE) # plot sparkline
	points(x=c(tmin,tmax),y=c(ymin,ymax),pch=19,col=c("red","blue"),cex=0.5) # plot min and max points
	text(x=len,y=ymin,labels=signif(ymin,sigfigs),cex=0.5,pos=4,col="red") # show minimum value
	text(x=len,y=ymax,labels=signif(ymax,sigfigs),cex=0.5,pos=4,col="blue") # show maximum value
	text(x=len,y=(ymin+ymax)/2,labels=yfin,cex=0.5,pos=4) # show most recent value
	par(temppar) # restore graphics defaults
}

-- Jason Dieterle (email)