bootSim.R

require(ggplot2)
require(data.table)
require(parallel)
load_all("~/gazetools")

aTan <- function(x1,y1,x2,y2) {
  y = (y2-y1)
  x = (x2-x1)
  a <- abs(atan(y/x)) * (180/pi)
  if (y>=0 && x<0) {
    a <- 180 - a
  } else if (y<0) {
    if (x<=0)
      a <- 180 + a
    else
      a <- 360 - a
  }
  a
}

#' 21-in. SVGA color monitor (42.67x32.01cm)
#' NOTE: SVGA==800x600
#' New requirements:
#'   min_dist=4.31
#'   max_dist=8.69
#' End 11saccades or no suitable new
#' view_dist=87cm
bootSim <- function(N=1, a=1.0) {
  out <- data.table()
  for (i in 1:N) {
    saccades=0
    x = runif(1,0,800)
    y = runif(1,0,600)
    repeat {
      repeat {
        x1 = runif(1,0,800)
        y1 = runif(1,0,600)
        d = subtended_angle(x,y,x1,y1,800,600,42.67,32.01,87)
        if (d>4.31 && d<8.69) break
      }
      x = c(x, x1)
      y = c(y, y1)
      saccades = saccades + 1
      if (saccades==3) break
    }
    repeat {
      repeat {
        lag = sample(1:3,1)
        xo = x[4-lag]
        yo = y[4-lag]
        if (xo!=x[4] && yo!=y[4])
          break
      }
      do = subtended_angle(x[4],y[4],xo,yo,800,600,42.67,32.01,87)
      tries = 0
      repeat {
        tries = tries + 1
        xn = runif(1,0,800)
        yn = runif(1,0,600)
        dn = subtended_angle(x[4],y[4],xn,yn,800,600,42.67,32.01,87)
        dno = subtended_angle(xn,yn,xo,yo,800,600,42.67,32.01,87)
        if (tries==1000 || (dn>4.31 && dn<8.69 && dno>4.31)) break
      }
      if (tries==1000) break
      a = aTan(x[3],y[3],x[4],y[4])
      an = aTan(x[4],y[4],xn,yn)
      ao = aTan(x[4],y[4],xo,yo)
      ans = "OLD"
      x1 = xo
      y1 = yo
      if (abs(a-an)<abs(a-ao)) {
        ans = "NEW"
        x1 = xn
        y1 = yn
      }
      out <- rbind(out, data.table(run=i,lag=lag,ans=ans))
      x = c(x[-1], x1)
      y = c(y[-1], y1)
      saccades = saccades + 1
      if (saccades==11) break
    }
  }
  out
}

#z <- mclapply(mclapply(1:16,function(x)bootSim(10000),mc.cores=16))