How it is calculated

Each bar of the window weighs exp(-(i - m)^2 / (2 s^2)), with i from 0 for the oldest bar to length minus 1 for the newest, m = offset times (length minus 1) and s = length / sigma. The weighted sum of the prices is divided by the sum of the weights. The first value comes once length bars are in.

Reference: Legoux 2009

How to read it

The offset moves the peak of the weighting: near 1 the line follows price closely, near 0 it is smooth and slow. A larger sigma narrows the bell, so fewer bars matter. Slope and the side price is on are read as with any average.

In a strategy

A responsive trend line, ctx.ind("alma", length=9, offset=0.85, sigma=6), or the cross of two ALMAs of different lengths as entry signal.

Inputs

Input	Type	Default	Range or choices
Length`length`	Whole number	`9`	min 1, max 5000
Offset`offset`	Number	`0.85`	min 0, max 1
Sigma`sigma`	Number	`6`	min 0.5, max 50
Source`source`	Price	`"close"`	close, open, high, low, hl2, hlc3, ohlc4, hlcc4

What it draws

Line	Drawn as
ALMA	Line

Used in

No strategy template reads it yet.