R/plot.alt.sample.size.R

In Auburngrads/SMRD: Statistical Methods For Reliability Data

#' @export
plot.alt.sample.size <-
function (x, 
          ALT.plan.values, 
          use.conditions, 
          quantile.of.interest = 0.1,
          xlim = c(NA, NA), 
          ylim = c(NA, NA), 
          conf.levels = c(0.8, 0.9, 0.95, 0.99), 
          grids = F, 
          my.title = NULL, 
          number.points = 100,...)
{
    if (missing(use.conditions)) {
        
        if (is.null(ALT.plan.values$use.conditions)) stop("\n Use conditions have not been specified.\n")
        use.conditions <- ALT.plan.values$use.conditions
        
    }
    accelvar.units <- ALT.plan.values$accelvar.units
    sigma <- ALT.plan.values$sigma
    distribution <- ALT.plan.values$distribution
    
    if (is.logdist(distribution)) {
        
        ylab <- "Confidence Interval Precision Factor R           "
        `if`(is.na(xlim[2]), Rupper <- 3, Rupper <- xlim[2])
        Rrange <- c(1.1, Rupper * 0.9)
        Rvec <- log.seq(Rrange[1], Rrange[2], length = number.points)
        xRvec <- logb(Rvec)
        
    } else {
        
        Rrange <- logb(c(1.1, 3)) * sigma
        ylab <- paste("Confidence Interval Half-Width D           ",
                      get.time.units(x))
        Rvec <- seq(Rrange[1], Rrange[2], length = number.points)
        xRvec <- Rvec
        
    }
    
    plan.string <- attr(x, "string.name") 
    if (is.null(plan.string)) plan.string <- deparse(substitute(x))
    plan.values.string <- attr(ALT.plan.values, "string.name")
    if (is.null(plan.values.string)) plan.values.string <- deparse(substitute(ALT.plan.values))
    
    if (is.null(my.title)) {
        
        `if`(is.logdist(distribution),
             my.title <- paste("Needed sample size giving approximately a 50% chance of having\n a confidence interval factor for the",
                               quantile.of.interest, "quantile that is less than R\n",
                               plan.string, plan.values.string, "\nuse conditions=",
                               paste(use.conditions, accelvar.units, collapse = ",")),
             my.title <- paste("Needed sample size giving approximatley a 50% chance of having\n a confidence interval half-width for the",
                               quantile.of.interest, "quantile that is less than D\n",
                               plan.string, plan.values.string, "\nuse conditions=",
                               paste(use.conditions, accelvar.units, collapse = ",")))
    }
    
    evaluate.results <- evaluate.alt.test.plan(x = x,
                                               ALT.plan.values = ALT.plan.values,
                                               use.conditions = use.conditions, 
                                               quantile.of.interest = quantile.of.interest)
    
    sample.size <- attr(evaluate.results, "sample.size")
    
    `if`(is.logdist(distribution),
         variance.factor <- sample.size * ((evaluate.results[[3]])/evaluate.results[[2]])^2,
         variance.factor <- sample.size * (evaluate.results[[3]])^2)
    
    ymatrix <- matrix(0, ncol = length(conf.levels), nrow = number.points)
    
    for (i in 1:length(conf.levels)) {
        
        zvalue <- quant(1 - (1 - conf.levels[i])/2, "normal")
        ymatrix[, i] <- ((zvalue^2) * variance.factor)/(xRvec^2)
        
    }
    
    xrna <- is.na(xlim)
    if (any(xrna)) xlim[xrna] <- range(Rvec)[xrna]
    yrna <- is.na(ylim)
    if (any(yrna)) ylim[yrna] <- range(ymatrix)[yrna]
    
    plot.paper(xlim, 
               ylim, 
               x.axis = "linear", 
               y.axis = "log",
               grids = grids, 
               cex = 1, 
               cex.labs = 1.2, 
               ylab = "Sample Size",
               xlab = ylab)
    
    abline(v = 1, lwd = 2, lty = 4)
    logymat <- logb(ymatrix)
    matlines(Rvec, logymat, col = 1, lty = 1, lwd = 2)
    
    for (i in 1:length(conf.levels)) {
        
        the.yloc <- logymat[number.points, i]
        text(x.loc(0.95), the.yloc, percent.conf.level(conf.levels[i]))
        
    }

    mtext(text = my.title, side = 3, line = 0.5, cex = 1.2)
}