[e2] Drawing Library :: Horizontal Ray

█ OVERVIEW
Library "e2hray"
A drawing library that contains the hray() function, which draws a horizontal ray/s with an initial point determined by a specified condition. It plots a ray until it reached the price. The function let you control the visibility of historical levels and setup the alerts.

█ HORIZONTAL RAY FUNCTION
hray(condition, level, color, extend, hist_lines, alert_message, alert_delay, style, hist_style, width, hist_width)
  Parameters:
    condition: Boolean condition that defines the initial point of a ray
    level: Ray price level.
    color: Ray color.
    extend: (optional) Default value true, current ray levels extend to the right, if false - up to the current bar.
    hist_lines: (optional) Default value true, shows historical ray levels that were revisited, default is dashed lines. To avoid alert problems set to 'false' before creating alerts.
    alert_message: (optional) Default value string(na), if declared, enables alerts that fire when price revisits a line, using the text specified
    alert_delay: (optional) Default value int(0), number of bars to validate the level. Alerts won't trigger if the ray is broken during the 'delay'.
    style: (optional) Default value 'line.style_solid'. Ray line style.
    hist_style: (optional) Default value 'line.style_dashed'. Historical ray line style.
    width: (optional) Default value int(1), ray width in pixels.
    hist_width: (optional) Default value int(1), historical ray width in pixels.
  Returns: void

█ EXAMPLES
 • Example 1. Single horizontal ray from the dynamic input.

//@version=5
indicator("hray() example :: Dynamic input ray", overlay = true)
import e2e4mfck/e2hray/1 as e2draw
inputTime = input.time(timestamp("20 Jul 2021 00:00 +0300"), "Date", confirm = true)
inputPrice = input.price(54, 'Price Level', confirm = true)
e2draw.hray(time == inputTime, inputPrice, color.blue, alert_message = 'Ray level re-test!') 
var label mark = label.new(inputTime, inputPrice, 'Selected point to start the ray', xloc.bar_time)

 • Example 2. Multiple horizontal rays on the moving averages cross.

//@version=5
indicator("hray() example :: MA Cross", overlay = true)
import e2e4mfck/e2hray/1 as e2draw
float sma1 = ta.​sma​(close, 20)
float sma2 = ta.​sma​(close, 50)
bullishCross = ta.crossover( sma1, sma2)
bearishCross = ta.crossunder(sma1, sma2)
plot(sma1, 'sma1', color.purple)
plot(sma2, 'sma2', color.blue)

// 1a. We can use 2 function calls to distinguish long and short sides.
e2draw.hray(bullishCross, sma1, color.green, alert_message = 'Bullish Cross Level Broken!', alert_delay = 10)
e2draw.hray(bearishCross, sma2, color.red,   alert_message = 'Bearish Cross Level Broken!', alert_delay = 10)  

// 1b. Or a single call for both.
// e2draw.hray(bullishCross or bearishCross, sma1, bullishCross ? color.green : color.red) 

 • Example 3. Horizontal ray at the all time highs with an alert.

//@version=5
indicator("hray() example :: ATH", overlay = true)
import e2e4mfck/e2hray/1 as e2draw
var float ​ath​ = 0, ​ath​ := math.max(high, ​ath​)
bool newAth = ta.change(​ath​)
e2draw.hray(​nz​(newAth[1]), high[1], color.orange, alert_message = 'All Time Highs Tested!', alert_delay = 10)

Nota Keluaran:

v2
- xloc context switched from 'bar_index' to 'time'.
- alert_delay should be declared in minutes instead of bars.
- deep history reference bug fixed.