Category Archives: UDFs

Numerical solutions with CSpline

The CSpline function presented in a previous post  fits a series of cubic polynomial curves to a specified series of points, returning the Y values for listed intermediate X values.  I was recently asked if this could be reversed to … Continue reading

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Automating chart scale limits

Edit 22 Mar 2014:  Also see https://newtonexcelbach.wordpress.com/2012/11/25/automating-chart-scale-limits-update/ for improved version with download link, and example of plotting a chart from a formula entered as text. One of the more annoying things about Excel charts is that if you want to … Continue reading

Posted in Charts, Excel, UDFs, VBA | Tagged , , , , | 8 Comments

Analysis of RC circular sections – theory and code

The basic tasks involved in analysing the stresses and strains in a reinforced concrete section under combined bending and axial load are: Assuming a horizontal beam with the top of the beam in compression and the bottom in tension Find … Continue reading

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Reinforced concrete elastic analysis; Circular section

Previous posts have presented the theoretical background to finding stresses and strains in a reinforced concrete section built up of trapezoidal layers and subject to combined bending and axial loads.  A spreadsheet with User Defined Functions (UDFs) and open source code … Continue reading

Posted in Beam Bending, Concrete, Excel, Newton, UDFs, VBA | Tagged , , , , , , | 10 Comments

Calling a function as a variable – another example

The recent posts on the Inverse Quadratic Method and Brent’s Method, and on calling a function as a variable, are leading towards a user defined function (UDF) to analyse circular reinforced concrete sections under combined bending and axial load, but since … Continue reading

Posted in Concrete, Excel, Maths, UDFs, VBA | Tagged , , , , , | 3 Comments