log() - Pine Script Function

log()

Overview

log() calculates the natural logarithm (base e) of the supplied value. It is frequently used to convert price ratios into additive log returns or to undo an exp() operation.

Syntax

log(x) → series float

Parameters

Name	Type	Description
x	series int/float	Value whose natural logarithm to compute. Must be strictly greater than 0.

Returns

series float — the natural logarithm of x.

Remarks

• log() and math.log() are equivalent aliases.
• Passing a non-positive value (x <= 0) yields na.
• Combine with exp() to reverse the transformation: exp(log(x)) == x.

Example

//@version=5
indicator("Log return volatility", overlay=false)

period = input.int(20, "Return period")

// Convert price changes to log returns.
logReturn = log(close / close[period])

plot(logReturn, "Log return", color=color.new(color.blue, 0))
plot(ta.sma(logReturn, period), "Average", color=color.orange)

// Highlight unusually large log moves.
threshold = ta.stdev(logReturn, period) * 2.0
bgcolor(math.abs(logReturn) > threshold ? color.new(color.red, 90) : na)

See Also

• exp()
• math.log()
• math.log10()
• math.pow()