R/Acceptance.R

In Dodge: Acceptance Sampling Ideas Originated by H.F. Dodge

#' print methods for the Dodge package
#' 
#' Adds to the base functionality for the print() command. The accompanying
#' \code{plot} methods are more sophisticated.
#' 
#' These methods print the most necessary elements of the corresponding
#' objects.
#' 
#' @aliases print.AccSampPlan print.CurtSampPlan print.SeqSampPlan
#' @param x an object of class AccSampPlan, CurtSampPlan, or SeqSampPlan
#' @param ... further arguments passed to or from other methods.
#' @author Jonathan Godfrey
#' @seealso The corresponding plot method is far more interesting. See
#' \code{\link{plot.AccSampPlan}} for example.
#' @export
print.AccSampPlan = function(x,...){
print.default(x,...)
}

#' @export
print.CurtSampPlan = function(x,...){
print.default(x,...)
}


#' @export
print.SeqSampPlan=function(x,...){
print(data.frame(h1=x$h1, h2=x$h2, s=x$s))
}



#' plot methods for the Dodge package
#' 
#' Creates plots for analysing the design of an acceptance sampling procedure.
#' 
#' At this stage the \code{plot.AccSampPlan} method only plots the Operating
#' Characteristic (OC) curve, the Average (AOQ) and (ATI) against the
#' proportion (p) of product that is nonconforming. It also plots the curtailed
#' sample size or the average sample number (ASN) against p. Further
#' development is still required.
#' 
#' @aliases plot.AccSampPlan plot.CurtSampPlan plot.SeqSampPlan
#' @param x an object of class AccSampPlan, CurtSampPlan, or SeqSampPlan
#' @param y ignored
#' @param ... further arguments passed to or from other methods.
#' @author Jonathan Godfrey with some assistance from Raj Govindaraju
#' @examples
#' 
#' Plan1 = SSPlanBinomial(1000, 20,1, Plots=FALSE)
#' plot(Plan1)
#' 
#' @export
plot.AccSampPlan = function(x, y=NULL, ...){
    one.fig <- prod(par("mfcol")) == 1
plot(x$p, x$OC, type="l", 
ylab="Probability of Acceptance", 
xlab="Fraction Nonconforming p")

if(!is.null(x$ASN)){
if(one.fig){dev.new()}
plot(x$p, x$ASN, type="l", 
ylab="Uncurtailed average sample size", 
xlab="Fraction Nonconforming p")
}
if(!is.null(x$n)){
if(one.fig){dev.new()}
plot(x$p, x$n, type="l", 
ylab="Uncurtailed sample size", 
xlab="Fraction Nonconforming p")
}

if(one.fig){dev.new()}
plot(x$p, x$AOQ, type="l", 
ylab="AOQ", 
xlab="Fraction Nonconforming p")
title(paste("AOQL = ", formatC(max(x$AOQ))))

if(one.fig){dev.new()}
plot(x$p, x$ATI, type="l", 
ylab="ATI", 
xlab="Fraction Nonconforming p")
}



#' @export
plot.CurtSampPlan=function(x,y=NULL,...){
plot(x$p, x$ASN.full, type="l", ylim=c(1, x$n), ylab="ASN", col="red", lty=2)
par(new=TRUE)
plot(x$p, x$ASN.semi, type="l", ylim=c(1, x$n), ylab="", col="blue", lty=1)
legend("topright", legend =c("Fully Curtailed ASN","Semi-curtailed ASN"), lty=2:1, col = c("red", "blue"))
}


#' @export
plot.SeqSampPlan=function(x,y=NULL,...){
plot(x$k, x$accept, type="l", ylab=expression(d[k]), xlab="k", ylim=c(min(x$accept), max(x$reject)))
par(new=TRUE)
plot(x$k, x$reject, type="l", ylab="", xlab="", ylim=c(min(x$accept), max(x$reject)))
title("Sequential Acceptance Chart")
axis(1, tck = 1, col = "grey", lty = "dotted")
axis(2, tck = 1, col = "grey", lty = "dotted")
text(median(x$k), min(x$accept), "ACCEPT")
text(median(x$k), max(x$reject), "REJECT")
text(median(x$k), max(x$accept), "CONTINUE")
}