Std / Array Layer

Calculate the standard deviation of fixed-length numeric arrays. Similar to numpy.std() or R's sd(). Returns the sample (n-1) or population (n) standard deviation.

Mathematical form: $σ = \frac{\sum ( x - μ ) ^{2}}{n - dd o f}$

Example transformation (arrays of length 3):

arrays	std
[1, 2, 3]	1.0
[10, 10, 10]	0.0
[1, null, 3]	1.414
[2, 4, 6]	2.0

Common applications:

Measuring data spread
Analyzing variability
Detecting outliers
Quality control
Uncertainty estimation

Note: Arrays must have the same fixed length across all rows. Arrays with null values ignore nulls in calculation. Only works with numeric arrays.

Table

Select

column

The fixed-length numeric array column to analyze. Only supports numeric arrays:

Integer arrays: [1, 2, 3]
Float arrays: [1.5, 2.7, 3.2]
Mixed numeric arrays: [1, 2.5, 3] All arrays must have the same length. Non-numeric arrays will result in null values

Ddof

Delta Degrees of Freedom (ddof) for variance calculation:

1 (default): Sample variance (unbiased estimator)
0: Population variance (maximum likelihood estimator) Higher values increase the estimated variance.

Name for the new column. If not provided, the system generates a unique name. If AsColumn matches an existing column, the existing column is replaced. The name should follow valid column naming conventions.