Tag Archives: Excel

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

DigitGraph Spreadsheet and WebPlot Digitiser

I have posted here previously a spreadsheet that allows XY data to be extracted from images of graphs, maps or other images of objects in a single plane: How to digitise a scanned image. I have updated the instructions for the … Continue reading

Posted in Charts, Charts, Computing - general, Curve fitting, Drawing, Excel, UDFs, VBA | Tagged , , , , , | 5 Comments

Asymmetric Catenary Function

Back in 2009, I posted a user defined function (UDF) to generate a catenary curve, that could be used together with the Excel Solver to generate a curve of a specified span and sag: A catenary function Following a discussion … Continue reading

Posted in Coordinate Geometry, Curve fitting, Excel, Maths, Newton, UDFs, xlwings | Tagged , , , , | Leave a comment

Using Excel Solver from VBA

Using the “record macro” icon in Excel to record the solver process, I had a couple of problems: When I tried to run the recorded macro, I got the message “Compile Error – Sub or Function not defined”. When that … Continue reading

Posted in Excel, VBA | Tagged , , , , | 1 Comment

Column buckling under multiple loads

Following another buckling discussion at Eng-tips I have modified my Frame4-buckle spreadsheet to allow input of multiple axial loads at any point along the column, along with any number of sections with different section properties.  Background on the method used … Continue reading

Posted in AlgLib, Beam Bending, Excel, Finite Element Analysis, Frame Analysis, Newton, UDFs, VBA | Tagged , , , , , , , , , | Leave a 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 , , , , , , , , | Leave a 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

Posted in Arrays, Excel, UDFs | Tagged , , , , , | Leave a comment