inst/apps/power_calculator/server.R

In Auburngrads/teachingApps: Apps for Teaching Statistics, R Programming, and Shiny App Development

server = function(input, output, session) {
  
output$nor.nor <- renderPlot({
  
 param1 <- c(input$norm1.1,input$norm1.2)
 param2 <- c(input$norm2.1,input$norm2.2)
 probs <- seq(.00001,.99999, length = 500)
 x.span1 <- qnorm(probs, param1[1], param1[2])
 x.span2 <- qnorm(probs, param2[1], param2[2])
 x.range <- seq(min(x.span1, x.span2),max(x.span1, x.span2), length = 500)
 y.span1 <- dnorm(x.range, param1[1], param1[2])
 y.span2 <- dnorm(x.range, param2[1], param2[2])
 plot(x = x.range,
      y = y.span1, 
      col = 1, type = 'l', lwd = 3, yaxs = 'i',
      xlim = c(min(x.span1, x.span2),max(x.span1, x.span2)),
      ylim = c(min(y.span1, y.span2),max(y.span1, y.span2)*1.04),
      las = 1, xlab = 'Time (t)', ylab = 'f(t)')
 par(new = TRUE)
 plot(x = x.range,
      y = y.span2, 
      col = 2, type = 'l', lwd = 3, yaxs = 'i',
      xlim = c(min(x.span1, x.span2),max(x.span1, x.span2)),
      ylim = c(min(y.span1, y.span2),max(y.span1, y.span2)*1.04),
      las = 1, xlab = '', ylab = '',
      axes = FALSE)
             
dats <- data.frame(x.range, 
                  (log(y.span1)*as.numeric(y.span1>.001))/(log(y.span2)*as.numeric(y.span2>.001)))
             
pts <- which(rank(abs(1-(dats[,2])))==1)

if (min(x.span2) < min(x.span1)) {
  
  pts <- which(rank(round(abs(1-(dats[,2])), digits = 4))==2)
  
}

if(min(rank(round(abs(1-(dats[,2])), digits = 4))) <= 2) {
  
polygon(x = x.range,
        y = c(y.span2[1:pts],y.span1[(pts+1):length(y.span1)]), 
        col = alpha('purple', .4))
}
})

}