Tag Archives: SciPy

Using Alglib least-squares solvers

Posted on 23/09/2017 by dougaj4

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

Evaluating text and calling Python functions from Excel with xlwings

Posted on 23/08/2017 by dougaj4

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

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

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

Posted on 10/10/2016 by dougaj4

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

Posted on 02/10/2016 by dougaj4

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 , , , , , , , , | 2 Comments