The DRAWARROWUP function in ProBuilder language is used to visually annotate specific points on a trading chart by drawing an upward-pointing arrow. This function is typically used to highlight significant events or conditions, such as potential buy signals in technical analysis.

Syntax:

DRAWARROWUP(x1, y1) COLOURED(R, G, B, a)

The DRAWARROWUP function requires two parameters, x1 and y1, which specify the chart coordinates where the arrow should be drawn. The COLOURED function is optional and allows the user to specify the color of the arrow using RGB color codes and an alpha (transparency) value.

Example:

sto = Stochastic[10,3](close)
signal = average[5](sto)
rge = averagetruerange[10](close)
if sto[1] < 20 and sto crosses over signal then
    DRAWARROWUP(barindex[1], low[1] - rge/2) COLOURED(10, 255, 10)
endif
RETURN

In this example, the DRAWARROWUP function is used to draw an upward arrow when the Stochastic indicator crosses over its signal line, suggesting a potential buying opportunity. The arrow is drawn below the low price of the bar, adjusted by half the average true range (ATR), and is colored green.

Additional Information:

• Stochastic Indicator: A momentum indicator comparing a particular closing price of a security to a range of its prices over a certain period of time. The sensitivity of the oscillator to market movements is reducible by adjusting that time period or by taking a moving average of the result.
• Average True Range (ATR): An indicator that measures market volatility by decomposing the entire range of an asset price for that period.
• The COLOURED function's parameters (R, G, B, a) represent the red, green, blue color values and the alpha transparency, respectively. Alpha values range from 0 (completely transparent) to 255 (completely opaque).

This function is useful for traders who use visual cues to quickly assess trading opportunities based on technical analysis indicators.