Range Analysis

//@version=4
study("Range Analysis", overlay=true)

// find which bar is 5 days away from the current time
milliseconds_in_5days = 1000 * 60 * 60 * 24 * 5  // millisecs * secs * min * hours * days
// plot(milliseconds_in_5days, title="ms in 5d", style=circles) //debug
// subtract timestamp of the bar being examined from the current time
// if value is less than 5 days ago, set variable "leftborder" as true
// this is set true at the bar being examined as the left border of the 5 days lookback window range
leftborder = timenow - time < milliseconds_in_5days  // true or na when false
// plot(leftborder ? 1 : na, title="bar within leftborder")  //debug
// plot(time, title="bartime") //debug
// plot(timenow - time, title="timenow minus bartime")  //debug

// treat the last bar (most recent bar) as the right edge of the lookback window range
rightborder = barstate.islast

// initialize variable "max" as na
max = float(na)

// if bar being examined is not within the lookback window range (i.e., leftborder = false)
// change the variable "max" to be na
// else, test if value of "max" stored in the previous bar is na
// (bcuz first bar being examined in the lookback window will not have a previous value ),
// if it is na, use the high of the current bar,
// else, use the value of "max" stored in the previous bar
max := not leftborder ? na : na(max[1]) ? high : max[1]
// plot(max ? max : na, title="max b4 compare")  // debug

// compare high of current bar being examined with previous bar's high
// if curr bar high is higher than the max bar high in the lookback window range
if high > max  // we have a new high
    max := high  // change variable "max" to use current bar's high value
    max
// else keep the previous value of max as the high bar within this lookback window range
// plot(max ? max : na, title="max after compare")  //debug

// if examining the last bar (newest bar, rightborder is true)
// set variable "val" to the previous value of series variable "max"
// else set to na so nothing is plotted
val = rightborder ? max[1] : na

// if val is true (a number, not na)
// plot character
// since no character is specified, a "star" will be plotted
// location.absolute uses the value of val as the y axis value
// the x axis location will be the last bar (newest bar)
plotchar(val, size=size.normal, location=location.absolute)

// fill the background of the 5 days lookback window range with aqua color
bgcolor(leftborder and not rightborder ? color.aqua : na, transp=70)