Category Archives: VBA

Python Traps

Posted on 01/01/2020 by dougaj4

When converting existing VBA code to Python there are a number of obvious changes to the syntax that need to be made for the code to run at all, but there are also a number of not so obvious traps … Continue reading →

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

A problem with integers in VBA

Posted on 01/10/2019 by dougaj4

A recent question at Quora asked: “Why am I getting an overflow error in Excel VBA when doing a simple arithmetic calculation like str1 = 24*60*30 where str1 is a variant or long or double?” I hadn’t encountered that problem … Continue reading →

Posted in Excel, UDFs, VBA | Tagged , , , | Leave a comment

Plotting Mandelbrot

Posted on 15/09/2019 by dougaj4

There are many sites discussing the Mandelbrot Set, but not many examples using VBA to plot the set in Excel, so here is my effort: The spreadsheet (including open source VBA code) may be downloaded from: Mandelbrot chart.zip Note that … Continue reading →

Posted in Charts, Charts, Coordinate Geometry, Drawing, Excel, Maths, Newton, VBA | Tagged , , , | 3 Comments

64 bit Excel and PtrSafe

Posted on 31/07/2019 by dougaj4

Installing my Office 365 subscription on a new computer I discovered it had decided (without asking) to upgrade itself to the 64 bit version, which resulted in some of my spreadsheets not working on the new system.  The main problem … Continue reading →

Posted in Excel, VBA | Tagged , , , , | 1 Comment

Solving the Lagrangian Point equation for the Moon

Posted on 23/06/2019 by dougaj4

This post was prompted by a recent question at Fitting high order polynomials, asking for Excel methods to solve the equations for the radius of the Moon’s Lagrangian Point 1. All the methods described in this post have been added to … Continue reading →

Posted in Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , | 4 Comments