This is a beta version of the Excel 2010 XLL Software Development Kit (SDK). The SDK exposes all relevant Excel 2010 functionality to XLL add-in developers, and introduces two new "power UDF" capabilities - Asynchronous user-defined functions (UDF), and HPC function remoting. The purpose of the SDK is twofold: 1. To make sure that all relevant Excel 2010 functionality is available to XLL add-in developers. This includes all new worksheet functions, and the ability to create 64-bit versions of XLL add-ins. 2. To introduce two exciting new "power UDF" capabilities: Asynchronous UDFs; and remoting function calls to HPC (High-Performance Computing) clusters.
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