Category Archives: Arrays

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

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LinEstGap with non-linear functions

The LinEstGap user defined function (UDF) allows the built-in Linest function to be used on data with empty cells or hidden rows, returning results that agree with the chart trend-line function, which automatically ignores blank cells and hidden data.  It … Continue reading

Posted in Arrays, Curve fitting, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , , , , | 1 Comment

Python Traps

When converting existing VBA code to Python there are a number of obvious changes to the syntax that need to be made for the code to run at all, but there are also a number of not so obvious traps … Continue reading

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

Excel Dynamic Arrays

Previews of dynamic arrays in Excel have been available for some time through the “Insider” programme.  They are now being published to general subscribers through Office 365 monthly updates: Further information is given at: Easier array formulas and Dynamic array … Continue reading

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Using conditional formatting with array formulas

A recent Quora question asked “How do I highlight the number closest to an initial number in a row in Excel?“.  The answer by Bill Jelen provides a good example of using conditional formatting with an array formula: In my … Continue reading

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Working with dynamic arrays in Excel

Many of the VBA functions available here return results as arrays, which must be entered by selecting the desired output range, then  pressing Ctrl-Shift-Enter (CSE).  This can be inconvenient (or at least untidy) when the size of the output array varies.  … Continue reading

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Transferring large arrays with Pyxll

Pyxll is a commercial Excel add-in linking Excel and Python.  The latest version  offers greatly improved performance in transferring data between Excel and Python as Numpy arrays, amongst many other new features and improvements. To check what this means in practice, … Continue reading

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