Tag Archives: Excel

Daily Download 18: Simultaneous Equations and Matrix Arithmetic Functions

Posted on 04/10/2012 by dougaj4

Today’s downloads collect several spreadsheets related to solution of simultaneous equations and matrix arithmetic, some of which were presented previously as part of the ALGLIB library (Daily Download 13). Solving simultaneous equations described how to solve simultaneous equations using the Excel … Continue reading →

Posted in AlgLib, Excel, Link to dll, Maths, Newton, UDFs, VBA | Tagged , , , , , , , | Leave a comment

Daily Download 17: Numerical Integration

Posted on 03/10/2012 by dougaj4

Some simple numerical integration functions (using the trapezoidal rule and Simpson’s Rule) were included in the Eval2 spreadsheet, presented on Daily Download Day 15, but for purposes were better accuracy and/or higher speed are required more sophisticated methods will do a … Continue reading →

Posted in AlgLib, Excel, Maths, Newton, Numerical integration, 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

Daily Download 15: Evaluation of formulas in text

Posted on 01/10/2012 by dougaj4

VBA has an Evaluate function that returns the numerical value of any text string representing a mathematical formula, but this is not directly available from the spreadsheet.  Today’s download is a User Defined Function (UDF) to provide this functionality, together with examples … Continue reading →

Posted in Excel, Maths, Newton, Numerical integration, UDFs, VBA | Tagged , , , , , | 1 Comment

Daily Download 14: Curve Fitting 1

Posted on 01/10/2012 by dougaj4

Today’s download topic covers fitting a straight line or curve to scattered data, using the “least squares” method.  Fitting a spline curve to pass exactly through a series of points will be covered in a few days. Use of the … Continue reading →

Posted in AlgLib, Charts, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , , | Leave a comment