Recent Comments
Bill Harvey on Units4Excel Update 
dougaj4 on Units4Excel Update Bill Harvey on Units4Excel Update dougaj4 on Units4Excel Update Bill Harvey on Units4Excel Update Units4Excel Update |… on Extracting text from an Intern… dougaj4 on Using LinEst() on data with… More on RC design of… on Reinforced Concrete Design for… 
AndyF83 on Using LinEst() on data with… dougaj4 on Extracting text from an Intern… 
Kirby on Extracting text from an Intern… Extracting text from… on Evaluating text with units and… dougaj4 on Deflections and Moments in Rec… 
Kaushal on Deflections and Moments in Rec… 
Kurt Clark on Working with units in Excel…
Category Archives: Curve fitting
Deflections and Moments in Rectangular Plates
Following a question here I have compared tabulated coefficients for deflections and bending moments in a rectangular plate with results of a Strand7 analysis using 8 noded plate/shell elements. The results are summarised below, and in a spreadsheet which also … Continue reading
Posted in Beam Bending, Curve fitting, Excel, Finite Element Analysis, Newton
Tagged Excel, FEA, Linest, Moody, Pilkey, plate bending, plate deflections, Plate stresses, Roark, Strand7, Timoshenko
2 Comments
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 Excel, Exponential curves, Linest, Linest with gaps, Log curves, non-linear curve fitting, Polynomial curves, Power curves, UDF, VBA
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 DigitGraph, digitize scanned image, Excel, UDF, VBA, WebPlot Digitizer
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 Catenary, Excel, Solver, UDF, VBA
Leave a comment
More circle fitting options with Scipy
A comment on the first post on this topic found that the method used did not work well for short arcs of large radius circles. An example of the problem can be seen in the screen shots below: The function … Continue reading
Posted in Coordinate Geometry, Curve fitting, Excel, Link to Python, Maths, Newton, NumPy and SciPy, UDFs, VBA, xlwings
Tagged curve fitting, Excel, least squares, Numpy, ODR, Python, SciPy, VBA
Leave a comment
