Category Archives: Coordinate Geometry

Daily Download 23: Trigonometric Functions in VBA and Fortran

Posted on 09/10/2012 by dougaj4

The trigonometric functions provided in Excel omit some functions, and the functions provided in VBA are still more restricted.  Notably VBA does not provide an ATan2 function, which is required to define an angle over a full 360 degree range, based on X, … Continue reading →

Posted in Coordinate Geometry, Excel, Link to dll, Maths, Newton, UDFs, VBA | Tagged , , , , , | 8 Comments

Daily Download 22: Splines and Curves

Posted on 08/10/2012 by dougaj4

Since it was first published in 2009 my CSpline function has been the most popular download from this site.  CSpline (and various associated functions) is used to fit a series of cubic curves through specified points, allowing interpolation along a smooth … Continue reading →

Posted in AlgLib, Beam Bending, Charts, Charts, Coordinate Geometry, Excel, Newton, Numerical integration, UDFs, VBA | Tagged , , , , , , , , | 7 Comments

Daily Download 20: Section Properties

Posted on 06/10/2012 by dougaj4

The download spreadsheets today provide functions to find section properties of shapes either defined by coordinates or selected from a list of shape types.  The section properties found are: area, first and second moments of area about the X and Y … Continue reading →

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

Daily Download 16: Intersections, interpolations, and rotations

Posted on 02/10/2012 by dougaj4

There is only one download file today: http://interactiveds.com.au/software/IP2.ZIP , but it contains a wealth of different functions dealing with 2D and 3D geometry, including intersections of lines, circles and spheres, simple interpolation functions, and functions for rotating points in 2D … Continue reading →

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

Geometry for Joiners

Posted on 03/04/2012 by dougaj4

A question came up on the ABC Self-Service-Science Forum, asking for a solution to find the dimensions of a diagonal brace looking like the diagram below: The solution is not as simple as it might look because the angle of … Continue reading →

Posted in Coordinate Geometry, Excel, Newton, UDFs, VBA | Tagged , , , , , , | 1 Comment