# standardDeviation(deltaDegreesOfFreedom:) Returns the standard deviation of the floating-point column’s elements. ``` func standardDeviation(deltaDegreesOfFreedom: Int = 1) -> FilledColumn.Element? ``` ## Parameters `deltaDegreesOfFreedom` A nonnegative integer. The method calculates the standard deviation’s divisor by subtracting this parameter from the number of non-`nil` elements (`n - deltaDegreesOfFreedom` where `n` is the number of non-`nil` elements). ## Return Value The standard deviation; otherwise, `nil` if there are fewer than `deltaDegreesOfFreedom + 1` non-`nil` items in the column. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)