Adds data curve fitting, interpolation and data smoothing functions to Excel. Functions include polynomial fits, several types of splines, and local regressions. Filters include moving average, Gaussian smoothing and median filtering.

Version: 2.80Data Curve Fit Creator Add-in is an easy-to-use data analysis add-in for Microsoft Excel. It adds curve fitting, interpolation, and data smoothing functions to Excel.
License: Free To Try $79.95
Operating System: Windows
Homepage: www.srs1software.com
Developed by:
Curve fitting functions include polynomial fits and a versatile local regression (loess) function. Interpolations include linear, cubic spline, bessel and monotonic 'constrained' splines, as well as a 'flexible spline' that allows you to specify the slope at each data point.
Cubic spline function coefficients and slope can also be returned. Data smoothing functions include moving average, median filter, and a Gaussian smoothing filter.
Data Curve Fit Creator Add-in also includes automatic sorting and data repair functions.
Version 2.80: Added new separate utility for updating or repairing function links in multiple Excel Workbooks.
Version 2.71: Minor fixes and improvements
Version 2.70: Added new 'Cubic Spline Extra Val' function which returns cubic spline function coefficients and slope at any point. Also added new calculation options to Cubic Spline function. Custom ribbon menu and Excel formula category added as well.
Version 2.62: Added two new spline interpolation functions: bessel and oneway (monotonic) splines. Also added support for date-time data interpolation. Fixed problems with 64 bit Excel 2013.
Version 2.3: Added support for 64 bit version of Microsoft Excel
Version 2.12: Added video demos, and improved performance with Windows 7
Version 2.10: Improved ease of use