Category Archives: Arrays

Brent’s Method; Update and Examples

Posted on 06/12/2017 by dougaj4

Brent’s Method is a refinement of Newton’s Method for the numerical solution of any equation with one variable.  The User Defined Function (UDF) QuadBrent was described in:  The Inverse Quadratic Method 3 – Brent’s Method Following a recent question, I have … Continue reading →

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

Tables and VBA

Posted on 25/10/2017 by dougaj4

I don’t use Excel Tables much, and not at all from VBA (where they are known as ListObjects), but that should probably change, so here are four links with comprehensive help on using Tables from VBA: The Spreadsheet Guru- VBA … Continue reading →

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

Setting up UDF Applications

Posted on 09/09/2017 by dougaj4

Following a recent comment, this post looks at setting up a user defined function (UDF) on a blank worksheet, using the ConBeamU function as an example. To use a UDF, the VBA code for the function must either be included … Continue reading →

Posted in Arrays, Beam Bending, Excel, Finite Element Analysis, 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

Indexing NumPy arrays with floats …

Posted on 01/04/2017 by dougaj4

… now you can’t. I recently updated to the latest version of NumPy (1.12.1), and today I discovered that some of my spreadsheets using NumPy arrays (via xlwings) were returning errors like: IndexError: only integers, slices (`:`), ellipsis (`…`), numpy.newaxis … Continue reading →

Posted in Arrays, Excel, Link to Python, NumPy and SciPy, UDFs, VBA | Tagged , , , , , | 2 Comments