Tag Archives: Cubic spline

Update to AL-Spline-Matrix

The AL-Spline-Matrix spreadsheet contains a large number of VBA user defined functions (UDFs) performing spline fitting and matrix operations, using the free and open source ALGLIB library. It was recently pointed out that the Excel interface code for the CSplineFitCW1da … Continue reading

Posted in AlgLib, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , | 1 Comment

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

Posted in AlgLib, Beam Bending, Charts, Charts, Coordinate Geometry, Excel, Newton, Numerical integration, UDFs, VBA | Tagged , , , , , , , , | 7 Comments

Alglib Spline Functions 1.32

Following a comment to AlgLib Spline Functions, the AL-Spline-Matrix spreadsheets have been updated, and may be downloaded from AL-Spline-Matrix03 for Excel 2003 and earlier and AL-Spline-Matrix07 for Excel 2007 and 2010.

Posted in AlgLib, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , , , , , | Leave a comment

Revision to CSpline2.xls

It was recently reported to me that the cubic spline spreadsheet CSpline2.xls (posted here) was crashing on loading in Excel 2003.  It seems that the problem was with the ChartSpline function, and that there are no problems if this function is … Continue reading

Posted in Drawing, Excel, Maths, UDFs, VBA | Tagged , , | 6 Comments

SplineBeam update

Previous SplineBeam post I have modified the SplineBeam spreadsheet to allow input of a single span (simply supported or with end constraints), and to optionally allow input of the position of intermediate nodes, rather than dividing each span into equal segment lengths.  This … Continue reading

Posted in Arrays, Beam Bending, Excel, Frame Analysis, Newton, UDFs, VBA | Tagged , , , , | 1 Comment