# init(operation:alpha:beta:iA_desc:iB_desc:o_desc:) Returns a new tensor-contraction parameters structure. ``` init(operation: UnsafePointer, alpha: Float, beta: Float, iA_desc: BNNSNDArrayDescriptor, iB_desc: BNNSNDArrayDescriptor, o_desc: BNNSNDArrayDescriptor) ``` ## Parameters `operation` The string that describes the operation. `alpha` Scaling that the operation applies to the result. `beta` A value, that must be either 0.0 or 1.0, you use to scale the existing output before the operation adds it to the result. `iA_desc` The descriptor of input matrix *A*. `iB_desc` The descriptor of input matrix *B*. `o_desc` The descriptor of the output. --- 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)