Tag Archives: Python

Indexing NumPy arrays with floats …

… 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 , , , , , | Leave a comment

The meaning of = in Python

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 , , , , , , , , , | 2 Comments

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

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 , , , , , , | Leave a comment

Debugging with xlwings and PyCharm

The xlwings documentation covers de-bugging, but it is very brief and it took me some time to get everything working, so this article covers the process in a bit more detail.  The details are affected by the editor being used, … Continue reading

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Transferring and converting strings in Excel and Python

The load table for the 3D Frame spreadsheet has a column listing the global axis for each load as text (X, Y, or Z).  In the VBA version the table is converted to a variant array, and the axes are handled … Continue reading

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Non-linear frame analysis; moment curvature and self-weight

The Python/Fortran/Excel frame analysis program (previous version here) now has several new features added to the 2D-solver routines: The beam bending behaviour may now be specified with moment-curvature tables, rather than the linear-plastic behaviour required in the previous version. Beam … Continue reading

Posted in Arch structures, Beam Bending, Concrete, Excel, Finite Element Analysis, Fortran, Frame Analysis, Link to dll, Link to Python, NumPy and SciPy, Strand7, VBA | Tagged , , , , , , , , , , , , , | 1 Comment

xlwSciPy 1.09 – update for xlwings 0.10 and Scipy 0.18.1

The xlwSciPy spreadsheet (last presented here) has been updated for the latest version of xlwings and Scipy. The new spreadsheet can be downloaded from: xlScipy-xlw.zip including full open source code. The spreadsheet requires Python, including xlwings, Numpy, Scipy and Pandas … Continue reading

Posted in Arrays, Curve fitting, Excel, Link to Python, Maths, NumPy and SciPy, Python Pandas, UDFs, VBA | Tagged , , , , , , , , | 1 Comment