Category Archives: UDFs

Converting a formula to values

Posted on 17/08/2017 by dougaj4

Excel has a built-in function (FormulaText) to display a formula as cell references, rather than the result value.  It would be useful to be able to display the value of each cell reference as well, but there is no built-in … Continue reading →

Posted in Excel, UDFs, VBA | Tagged , , , | 2 Comments

Excel to Alglib via xlwings

Posted on 11/08/2017 by dougaj4

The Alglib library provides many valuable numerical analysis routines, but the VBA version is no longer actively maintained.  The latest versions are available in C++, C#, and Python, of which the Python version (in conjunction with xlwings) provides the easiest interface … Continue reading →

Posted in AlgLib, Curve fitting, Excel, Link to Python, Maths, Newton, Numerical integration, UDFs, VBA, xlwings | Tagged , , , , , , , , , | 12 Comments

Stress increments in prestressed concrete beams

Posted on 02/07/2017 by dougaj4

The two main Australian Standards covering prestressed concrete structures (AS 3600, Concrete Structures, and AS 5100 Part 5, Concrete Bridges) put a limit on the allowable increase in stress in reinforcement and prestressing strands and tendons, when the load increases from … Continue reading →

Posted in Beam Bending, Concrete, Excel, Newton, UDFs, VBA | Tagged , , , , , , | 2 Comments

Plotting Freeze-Thaw Data …

Posted on 21/06/2017 by dougaj4

… or other irregular cyclic data. Another Eng-Tips question asked how to approximate ice area over a freeze-thaw cycle using a function based on a sine or cosine curve.  The screen-shot below shows three alternatives: Using built in Excel functions requires … Continue reading →

Posted in Arrays, Curve fitting, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , | 1 Comment

Counting non-pecked chicks

Posted on 16/06/2017 by dougaj4

Download file:  Binary Chicks.zip. This post is based on a recent discussion at Cosmic Horizons looking at numerical methods to solve the following problem: The answer to the question is straightforward: With a little thought, you should be able to realise … Continue reading →

Posted in Excel, Link to Python, Maths, Newton, UDFs, VBA, xlwings | Tagged , , , , , , , | Leave a comment