Category Archives: UDFs

Complex Numbers and Solving Quartic Polynomial Equations

Posted on 19/09/2010 by dougaj4

It was recently pointed out to me that the User Defined Function (UDF) for solving quartic polynomial equations presented in this post returned an error for some input values.  In tracking down the source of the error I decided that it … Continue reading →

Posted in AlgLib, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , | 3 Comments

Eval.xls and the ALGLIB integration functions.

Posted on 11/09/2010 by dougaj4

In a comment on a previous post on numerical integration I mentioned that I might implement the ALGLIB integration functions using the same technique, that is using the VBA Evaluate function to evaluate functions entered as text in the spreadsheet.  Well … Continue reading →

Posted in AlgLib, Excel, Maths, Newton, Numerical integration, UDFs, VBA | Tagged , , , , | 4 Comments

2D Spline Interpolation with ALGLIB

Posted on 20/08/2010 by dougaj4

I have updated the ALGLIB Spline and Matrix Function spreadsheet to include 2D interpolation of tabular data, including both linear and cubic spline interpolation.  The spreadsheet including the new functions with full open source code may be downloaded from AL-Spline-Matrix03.zip … Continue reading →

Posted in AlgLib, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , | 6 Comments

ALGLIB Statistics Functions

Posted on 16/08/2010 by dougaj4

I have recently imported all the ALGLIB statistics functions into VBA, and written interface functions where required, so that all the functions may now be used as User Defined Functions (UDFs) on the spreadsheet.  A spreadsheet including full open source code … Continue reading →

Posted in AlgLib, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , | 4 Comments

The hole through the middle of the Earth – filled with air

Posted on 13/08/2010 by dougaj4

Three air molecules go into a hole,  Well, I say three; could have been four or five.  Could have been nine or ten, doesn’t matter. Could have been fifteen, twenty – fifty. Round it up. Hundred. Let’s go mad, eh … Continue reading →

Posted in AlgLib, Differential Equations, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , | 4 Comments