Category Archives: UDFs

Two new functions for IP.xls

Posted on 18/07/2009 by dougaj4

Edit 8 Feb 2012: The functions described below have been superseded by new versions which are described at https://newtonexcelbach.wordpress.com/2009/08/18/finding-circle-centres-in-3d/.  That link also gives a description (with diagrams!) of how the functions work.  The download file for the new versions is … Continue reading →

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

More on cubic splines

Posted on 12/07/2009 by dougaj4

Link to Cubic Spline Update The previous two posts used cubic splines with the “natural” end condition, that is with an end curvature of zero.  To apply the cubic spline to analysis of continuous beams with different end conditions we … Continue reading →

Posted in Beam Bending, Excel, Frame Analysis, Maths, Newton, UDFs, VBA | Tagged , , , , | 10 Comments

Continuous beam analysis with cubic splines

Posted on 05/07/2009 by dougaj4

The last example in the previous post illustrated the use of cubic splines to find the bending moments in a continuous beam subject to prescribed lateral displacements.  A similar technique can be used to find bending moments, shear forces, reactions, … Continue reading →

Posted in Arrays, Beam Bending, Excel, Finite Element Analysis, Frame Analysis, Maths, Newton, UDFs, VBA | Tagged , , , , , , , | 9 Comments

Cubic Splines

Posted on 02/07/2009 by dougaj4

Cubic splines are used to fit a smooth curve to a series of points with a piecewise series of cubic polynomial curves.  In addition to their use in interpolation, they are of particular interest to engineers because the spline is … Continue reading →

Posted in Beam Bending, Excel, Newton, UDFs, VBA | Tagged , , , , | 73 Comments

A catenary function

Posted on 25/06/2009 by dougaj4

Following on from the previous post, here is an Excel User Defined Function (UDF) to calculate the coordinates of any specified catenary, with the option of also finding the tension force at any point. Download from: Catenary.zip The download file … Continue reading →

Posted in Arch structures, Excel, Maths, Newton, UDFs, VBA | 3 Comments