Tag Archives: SciPy

Using Alglib least-squares solvers

Following the last post on using the Python version of Alglib from Excel, via xlwings, this post looks in more detail at alternatives for fitting a non-linear function to a set of data, using the Levenberg-Marquardt method.  The spreadsheet with … Continue reading

Posted in AlgLib, Curve fitting, Excel, Link to Python, Maths, Newton, NumPy and SciPy, UDFs, VBA, xlwings | Tagged , , , , , , , , , , | Leave a comment

Evaluating text and calling Python functions from Excel with xlwings

The Alglib spreadsheet presented here includes functions to evaluate formulas entered as text on the spreadsheet, or to call specified Python functions.  I have now added a user defined function (UDF) that will perform either of these operations (xl_CallFuncD), and added … Continue reading

Posted in AlgLib, Excel, Link to Python, Maths, Newton, NumPy and SciPy, UDFs, VBA, xlwings | Tagged , , , , , , , , , | 1 Comment

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 , , , , , , | 3 Comments

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

Non-linear Frame Analysis – Scipy solvers

The frame analysis spreadsheet presented in the previous post has been updated to use the solvers included in the Scipy package.  There is now an option to use either the Cholesky solver, or an iterative sparse solver.  The main advantages of … Continue reading

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

xlwSciPy 1.7

Following recent posts on xlwings 0.7.1, dictionaries, and optional arguments and xlwings – dataframes and statistics, I have added the associated functions and examples to the xlwSciPy spreadsheet, and also updated it to xlwings 0.71. The new spreadsheet can be … Continue reading

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