Category Archives: UDFs

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

Extracting numbers from text – update

Posted on 11/03/2017 by dougaj4

I have previously posted a spreadsheet with user defined functions (UDFs) using regular expressions to extract numbers from a text string (see Extracting numbers from text and regular expressions). I have now modified the Extractnums function to optionally return the numbers … Continue reading →

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

The meaning of = in Python

Posted on 26/02/2017 by dougaj4

In VBA, if you have an array named a and a variant named b, then the statement “b = a” creates a new array b with the same size and values as a.  If the values of either a or b are subsequently changed, the values of the … Continue reading →

Posted in Arrays, Excel, Link to Python, NumPy and SciPy, UDFs, VBA | Tagged , , , , , , , , , | 4 Comments

ConBeamU 4.13

Posted on 22/02/2017 by dougaj4

The continuous beam analysis spreadsheet, ConBeamU, is now up to version 4.13 with some minor bug-fixes, and the addition of a non-linear option for the BeamAct functions. See ConBeamU for more details of the functions available in the spreadsheet. Download … Continue reading →

Posted in Beam Bending, Excel, Frame Analysis, Newton, UDFs, VBA | Tagged , , , , , , | 7 Comments

Weighted Least Squares Regression, using Excel, VBA, Alglib and Python

Posted on 05/02/2017 by dougaj4

Least squares linear regression in Excel is easy.  That’s what the Linest and Trend functions do.  That is, they find the coefficients of a straight line (or higher dimension shape) so that the sum of the squares of the distances of … Continue reading →

Posted in AlgLib, Curve fitting, Excel, Link to Python, Maths, Newton, NumPy and SciPy, UDFs, VBA | Tagged , , , , , , | 9 Comments