# Category Archives: Maths

## Iterative solvers and arrays

A recent thread at Eng-Tips was looking for a solution to the problem described  below: The solutions to this problem described below can be downloaded from: ItSolve.zip and xlScipy3.zip The ItSolve.xlsb spreadsheet contains a user defined function (UDF) to solve iterative … Continue reading

Posted in Arrays, Charts, Excel, Link to Python, Maths, Newton, NumPy and SciPy, UDFs, VBA, xlwings | Tagged , , , , , , , | 1 Comment

## Arc-spline update

The input for the first version of the Arcspline function required the coordinates of the centre of each arc, as well as the angle of the tangents at each end of the arc.  I have now added a new version with … Continue reading

Posted in Coordinate Geometry, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , | 7 Comments

## Using VBA Evaluate as an Array Function

I recently discovered from a thread at  Chandoo’s Excel Forum that the VBA Evaluate function can be used as an array function.  As a simple example: Range(“A11:A16”).Value = Evaluate(“= B11:B16 + C11:C16”) will add the values in columns B and C, … Continue reading

Posted in Arrays, Coordinate Geometry, Excel, Maths, UDFs, VBA | Tagged , , , , | 2 Comments

## Arcs and arc-splines

I have added two user defined functions (UDFs) to the IP2 spreadsheet to generate coordinates for a single  arc, or a series of arcs connected (if necessary) by straight lines.  The new version may be downloaded from: IP2.zip As an example … Continue reading

Posted in Animation, Charts, Charts, Coordinate Geometry, Drawing, Excel, Maths, UDFs, VBA | Tagged , , , , , , | 1 Comment

## Units and solvers with Pint and Sympy

Following the previous post I have adapted the units code to use the Pint package, and added a function using the Sympy equation solver, with Pint units.  I have applied the functions to finding the depth of neutral axis of a … Continue reading

Posted in Beam Bending, Concrete, Excel, Link to Python, Maths, Newton, UDFs, VBA, xlwings | | Leave a comment

## Working with units in Excel – using VBA and Python

One of the most frequent reasons given for not using Excel for engineering and scientific applications is its very limited  facilities for dealing with calculations involving units.  It is possible to overcome this deficiency with VBA (see  Daily Download 24: … Continue reading

Posted in Excel, Link to Python, Maths, Newton, NumPy and SciPy, UDFs, VBA, xlwings | | 4 Comments

## Scipy Statistics Functions – coding and getting help

The Python Scipy library currently has 84 statistics functions.  I have now updated the xlwSciPy3 spreadsheet to access all of them directly from Excel.  The new version can be downloaded from: xlwSciPy3.zip As usual, the download includes full open-source code.  … Continue reading

Posted in Excel, Link to Python, Maths, Newton, NumPy and SciPy, UDFs, VBA, xlwings | | Leave a comment