Tag Archives: vectors

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

Daily Download 25: Vector Functions

Posted on 12/10/2012 by dougaj4

Today’s download file provides a variety of vector arithmetic functions, which can be used either from other VBA routines, or on the spreadsheet as User Defined Functions. Download file: http://interactiveds.com.au/software/VectorFunc.xlsb In addition to Dot and Cross the spreadsheet contains the following … Continue reading →

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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

Area from Vectors

Posted on 27/08/2011 by dougaj4

The previous post looked at User Defined Functions (UDFs) for working with vectors, including examples of functions to find the area of polygons defined by coordinates.  In this post the functions will be extended to find other section properties (such … Continue reading →

Posted in Arrays, Coordinate Geometry, Excel, Maths, UDFs, VBA | Tagged , , , , , , | 5 Comments

Dots and Crosses

Posted on 21/08/2011 by dougaj4

The comments from Bill Harvey in the previous post prompted me to have a closer look at the functions available in Excel for working with vectors.  Here is a complete list of them: =SUMPRODUCT() (Equivalent to the vector dot product) This … Continue reading →

Posted in Arrays, Coordinate Geometry, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , | 11 Comments