Category Archives: NumPy and SciPy

Floating Point Precision Problems

A question on Quora : prompted me to look at how these numbers are handled in Excel, in VBA called from Excel, and in Python called from Excel via pyxll. The results are shown in the screenshot below: Column A … Continue reading

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

Python callable arguments from Excel

Many Scipy functions have “callable” arguments, i.e. functions that can be called, with the returned data used as input by the calling function. Types of callable arguments include: Functions in the active Python module Functions in any active loaded library … Continue reading

Posted in Excel, Link to Python, NumPy and SciPy, PyXLL, UDFs | Tagged , , , , , , , | Leave a comment

Python optional arguments from Excel – Part 2

The previous post provided a method for using pyxll to pass optional arguments from Excel to Python whilst preserving the default values of any called Python function for arguments that were omitted in the Excel function. One condition where this … Continue reading

Posted in Excel, Link to Python, NumPy and SciPy, PyXLL, UDFs, VBA | Tagged , , , , , | Leave a comment

Using Excel with Python and ctypes

The Strand7 API provides an interface between the Strand7 Finite Element Analysis program and external software. It works with many different languages, including Python, which uses ctypes to transfer data to and from the API functions. It is essential that … Continue reading

Posted in Beam Bending, Excel, Link to dll, Link to Python, NumPy and SciPy, PyXLL, Strand7, UDFs | Tagged , , , , , | Leave a comment

More Python Traps

I recently posted on some Python Traps, focussing on code where changes in the values of sub-routine arguments were not reflected in the calling routines.  The reverse can also be a problem: if an array, a, is passed to a … Continue reading

Posted in Arrays, Excel, Link to Python, Newton, NumPy and SciPy, PyXLL, UDFs | Tagged , , , , , | Leave a comment