Category Archives: Coordinate Geometry

Xlls, Maths and Plots; some useful links

Posted on 11/11/2013 by dougaj4

Two from regular commenter here, Keith Lewis: Excel xll add-in library: This is a library for creating xll add-ins for Excel from 97 through 2013. It makes every feature of the latest Excel SDK available to you including the big … Continue reading →

Posted in Coordinate Geometry, Excel, Link to dll, Maths, Newton | Tagged , , , | 3 Comments

Section properties for groups of defined shapes

Posted on 12/04/2013 by dougaj4

Following a discussion at Eng-Tips, I have modified the section properties spreadsheet (presented here) so that section properties can be found for groups of defined shapes, including provision for translation and rotation of each shape, and application of different E … Continue reading →

Posted in Coordinate Geometry, Excel, Maths, Newton, UDFs, VBA | Tagged , , , | 13 Comments

Precise Angles and XNumbers

Posted on 28/01/2013 by dougaj4

Further to comments by Georg under: The angle between two vectors, in 2D or 3D I have added four alternative ways of calculating the angle between two 3D vectors to the VectorFunc spreadsheet.  The new version can be downloaded from: http://interactiveds.com.au/software/VectorFunc.xlsb. … Continue reading →

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

Defining beam orientation in 3D

Posted on 19/01/2013 by dougaj4

The principal axes of a beam (or any 2D closed shape) are defined as the axes along which an applied load will not cause any deflection in the transverse direction.  In mathematical terms, if the beam cross-section is defined in the … Continue reading →

Posted in Beam Bending, Coordinate Geometry, Frame Analysis, Maths, Newton | Tagged , , , , | Leave a comment

The angle between two vectors, in 2D or 3D

Posted on 12/01/2013 by dougaj4

Finding the angle between two lines in 2D is easy, just find the angle of each line with the x-axis from the slope of the line and take the difference.  In 3D it is not so obvious, but it can … Continue reading →

Posted in Coordinate Geometry, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , | 9 Comments