Category Archives: Maths

Compiled AlgLib Matrix Functions for Excel

Posted on 27/05/2010 by dougaj4

This post describes a series of matrix functions compiled from the AlgLib library code (covered in previous posts) as a dll that can be called from Excel VBA, and used as User Defined Functions (UDFs).  A spreadsheet containing the necessary VBA … Continue reading →

Posted in Arrays, Excel, Link to dll, Maths, Newton, UDFs, VBA | Tagged , , , , , , | 18 Comments

Linking AlgLib C++ to Excel VBA

Posted on 22/05/2010 by dougaj4

The previous post described how to install AlgLib VBA routines in Excel.  It is also possible to make AlgLib c++ routines (compiled as dll’s) available from Excel, either from VBA, or using User Defined Functions (UDFs) directly from the spreadsheet.  Using compiled dll … Continue reading →

Posted in Excel, Link to dll, Maths, Newton, UDFs, VBA | Tagged , , , , , , , | 4 Comments

Installing AlgLib with Excel VBA

Posted on 20/05/2010 by dougaj4

In a previous post I linked to the AlgLib site which has an extensive range of mathematical routines available in VBA, c/c++ and pascal.  I have recently been experimenting with these (in reponse to a thread at the Eng-Tips forum), and will … Continue reading →

Posted in Arrays, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , , | 13 Comments

Cubic Hermitic and Cardinal Splines

Posted on 14/05/2010 by dougaj4

In my previous post on splines I described a quick and dirty approach to adjusting a cubic spline to fit monotonic data, which did not meet with universal approval, so I have followed up Mike Woodhouse’s link: (http://en.wikipedia.org/wiki/Monotone_cubic_interpolation) which gives a … Continue reading →

Posted in Charts, Excel, Maths, UDFs, VBA | Tagged , , , , , , | 8 Comments

Using Cubic Splines in Practice

Posted on 06/05/2010 by dougaj4

I recently had an interesting query from Georg,  a geography student in Germany regarding the use of cubic splines to fit a smooth curve to experimental data.  The graph he sent me is shown below: The cubic spline has produced … Continue reading →

Posted in Charts, Excel, Maths, Newton, UDFs | Tagged , | 9 Comments