Category Archives: AlgLib

Daily Download 22: Splines and Curves

Since it was first published in 2009 my CSpline function has been the most popular download from this site.  CSpline (and various associated functions) is used to fit a series of cubic curves through specified points, allowing interpolation along a smooth … Continue reading

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Daily Download 21: Assorted Solvers

Today’s download starts with some simple linear interpolation methods used to solve polynomial equations, leading on to more sophisticated methods using quadratic or inverse quadratic interpolation. Also included is a solver for differential equations using the Cash-Karp Method, which is … Continue reading

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Daily Download 18: Simultaneous Equations and Matrix Arithmetic Functions

Today’s downloads collect several spreadsheets related to solution of simultaneous equations and matrix arithmetic, some of which were presented previously as part of the ALGLIB library (Daily Download 13). Solving simultaneous equations described how to solve simultaneous equations using the Excel … Continue reading

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Daily Download 17: Numerical Integration

Some simple numerical integration functions (using the trapezoidal rule and Simpson’s Rule) were included in the Eval2 spreadsheet, presented on Daily Download Day 15, but for purposes were better accuracy and/or higher speed are required more sophisticated methods will do a … Continue reading

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Daily Download 14: Curve Fitting 1

Today’s download topic covers fitting a straight line or curve to scattered data, using the “least squares” method.  Fitting a spline curve to pass exactly through a series of points will be covered in a few days. Use of the … Continue reading

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