# polarToRectangular(_:) Returns double-precision rectangular coordinates converted from polar coordinates. ``` static func polarToRectangular(_ polarCoordinates: U) -> [Double] where U : AccelerateBuffer, U.Element == Double ``` ## Parameters `polarCoordinates` The source polar coordinates. ## Discussion The function calls the underlying [`vDSP_rectD`](/documentation/Accelerate/vDSP_rectD) function to convert the input angle-radius pairs to Cartesian x-y pairs. The following code shows how to convert an angle-radius pair (with the angle specified in degress) to its rectangular equivalent: ```swift let angle = Measurement(value: 45, unit: UnitAngle.degrees) .converted(to: UnitAngle.radians) .value let radius = sqrt(25.0 + 25.0) let polarCoordinates = [radius, angle] let rectangularCoordinates = vDSP.polarToRectangular(polarCoordinates) // Prints "[5.0, 5.0]". print(rectangularCoordinates) ``` --- 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)