# vvlogb(_:_:_:) Calculates the unbiased exponent of each element in an array of double-precision values. ``` func vvlogb(_: UnsafeMutablePointer, _: UnsafePointer, _: UnsafePointer) ``` ## Discussion ### Parameters: - parameter 1: The output array, *y*. - parameter 2: The input array, *x*. - parameter 3: The number of elements in the arrays. For a nonzero finite floating-point number `f`, `logb` is defined to be the integer that satisfies `abs(f) = significand * 2**logb(f)`, with `significand` in `[1,2)`. If `x` is `+/-0`, `y` is set to `-inf`. If `x` is `+/-inf`, `y` is set to `+inf`. If `x` is NaN, `y` is set to `NaN`. --- 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)