# vvfmod(_:_:_:_:) Calculates the modulus after dividing each element in an array by the corresponding element in a second array of double-precision values. ``` func vvfmod(_: UnsafeMutablePointer, _: UnsafePointer, _: UnsafePointer, _: UnsafePointer) ``` ## Discussion ### Parameters: - parameter 1: The output array, *z*. - parameter 2: The numerators input array, *y*. - parameter 3: The denominators input array, *x*. - parameter 4: The number of elements in the arrays. This function calculates *z=y-k*x*, for an integer k such that if x is nonzero, the result has the same sign as y and magnitude less than that of x. The following code shows an example of using [`vvfmod(_:_:_:_:)`](/documentation/Accelerate/vvfmod(_:_:_:_:)): ```swift var x: [Double] = [7, 4, 3, 4] var y: [Double] = [2, 5, 10, 30] var z = [Double](repeating: 0, count: x.count) var n = Int32(x.count) vvfmod(&z, &y, &x, &n) print(z) // [2.0, 1.0, 1.0, 2.0] ``` --- 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)