# Zero crossing search Count and find the zero crossings in a vector. ## Topics ### Single-Vector Zero Crossing Search The functions in this group find a specified number of zero crossings, returning the last crossing found and the number of crossings found. [`static func countZeroCrossings(U) -> UInt`](/documentation/Accelerate/vDSP/countZeroCrossings(_:)-3vfmd) Returns the number of zero crossings in a double-precision vector. [`static func countZeroCrossings(U) -> UInt`](/documentation/Accelerate/vDSP/countZeroCrossings(_:)-3btsl) Returns the number of zero crossings in a single-precision vector. [`extern void vDSP_nzcros(const float *__A, vDSP_Stride __IA, vDSP_Length __B, vDSP_Length *__C, vDSP_Length *__D, vDSP_Length __N);`](/documentation/Accelerate/vDSP_nzcros) Counts and finds the zero crossings in a single-precision vector. [`extern void vDSP_nzcrosD(const double *__A, vDSP_Stride __IA, vDSP_Length __B, vDSP_Length *__C, vDSP_Length *__D, vDSP_Length __N);`](/documentation/Accelerate/vDSP_nzcrosD) Counts and finds the zero crossings in a double-precision vector. --- 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)