Category Archives: UDFs

Calling a function as a variable

Posted on 08/04/2010 by dougaj4

The functions described in recent posts provide iterative solutions to polynomial equations, but the same method can be used for any equations that can be evaluated numerically and have a single variable.  The question then is, how can we call a … Continue reading →

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

The Inverse Quadratic Method – 2

Posted on 04/04/2010 by dougaj4

Firstly a clarification from the previous post in this series.  The method presented in that post was a direct application of quadratic interpolation, rather than the inverse quadratic method, as implied by the post title.  The inverse quadratic method will be … Continue reading →

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

Function roots with the Inverse Quadratic Method

Posted on 31/03/2010 by dougaj4

An earlier post presented various methods for finding the roots of polynomial functions based on the use of linear interpolation.  It is sometimes advantageous to use a quadratic interpolation function, and methods using this approach will be presented in this and following … Continue reading →

Posted in Excel, Maths, UDFs, VBA | Tagged , , , , | 5 Comments

Tension Stiffening

Posted on 12/03/2010 by dougaj4

Tension Stiffening in reinforced concrete is the increase in stiffness of a cracked member due to the development of tensile stresses in the concrete between the cracks.  The main application of tension stiffening theory in design applications is in the … Continue reading →

Posted in Beam Bending, Concrete, Excel, Newton, UDFs, VBA | Tagged , , , , , | 3 Comments

Stringing more than two words together

Posted on 01/03/2010 by dougaj4

It has always seemed strange to me that the Excel function Concatenate(), which has such a long name, provides no additional functionality over using the & operator. The TextString function is a simple User Defined Function (UDF) which provides the … Continue reading →

Posted in Excel, UDFs, VBA | Tagged , , , | 5 Comments