Tag Archives: UDFs

New AS 3600 and RC Design Functions 8

A revised version of the Australian Concrete Structures code, AS 3600, was recently published, with many significant changes, including: Changes to ULS reduction Factors Creep and shrinkage Curvature and deflection calculations Crack width calculation and stress limits Major  changes to … Continue reading

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Arc-spline update

The input for the first version of the Arcspline function required the coordinates of the centre of each arc, as well as the angle of the tangents at each end of the arc.  I have now added a new version with … Continue reading

Posted in Coordinate Geometry, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , | Leave a comment

Using VBA Evaluate as an Array Function

I recently discovered from a thread at  Chandoo’s Excel Forum that the VBA Evaluate function can be used as an array function.  As a simple example: Range(“A11:A16”).Value = Evaluate(“= B11:B16 + C11:C16”) will add the values in columns B and C, … Continue reading

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Working with units in Excel – using VBA and Python

One of the most frequent reasons given for not using Excel for engineering and scientific applications is its very limited  facilities for dealing with calculations involving units.  It is possible to overcome this deficiency with VBA (see  Daily Download 24: … Continue reading

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

Scipy Statistics Functions – coding and getting help

The Python Scipy library currently has 84 statistics functions.  I have now updated the xlwSciPy3 spreadsheet to access all of them directly from Excel.  The new version can be downloaded from: xlwSciPy3.zip As usual, the download includes full open-source code.  … Continue reading

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

Passing variable argument lists from Excel to Python via xlwings

When calling a Python function it is sometimes necessary to pass a variable number of arguments.  Examples from the xlw_Scipy spreadsheet include: Curve fitting functions, for which the functions to be fitted may have any number of arguments. The Scipy … Continue reading

Posted in Arrays, Excel, Link to Python, NumPy and SciPy, UDFs, VBA, xlwings | Tagged , , , , , , , , | 2 Comments

Returning Arrays From VBA and Python

Most  of the  user defined functions (UDFs) presented on this blog return a multi-cell array, that must be entered by selecting the output range then pressing Ctrl-shift-enter to display all the results.  This process has several inconveniencies: You need to know … Continue reading

Posted in Arrays, Excel, Link to Python, UDFs, VBA, xlwings | Tagged , , , , , , , | Leave a comment