Monthly Archives: June 2012

From VBA to C Part 5 – Some Pratfalls – the mistakes I keep making

I have been coding in VBA since Excel 5 (1993) so I keep trying to do VBA things in C, specially when I spend a few weeks doing VBA stuff and then switch back to C. Here are (just a … Continue reading

Posted in UDF, Uncategorized, VBA, XLL | 7 Comments

From VBA to C Part 4 – A small subset of simple C syntax

And just how fast can you say “A small subset of simple C syntax”? The benchmark  UDF In this post I am going to build a simple benchmark UDF. I have chosen the AverageTol UDF that was implemented as optimised … Continue reading

Posted in UDF, Uncategorized, VBA, XLL | 4 Comments

From VBA to C Part 3 – A “Hello Range” function

Lets start with something simple: an XLL function that just returns whatever you feed it as a parameter. Create an XLL project with VS 2010 and XLL Plus Installing Planatech XLL Plus integrates some XLL templates and Wizards into Visual … Continue reading

Posted in UDF, VBA, XLL | 3 Comments

From VBA to C Part 2 – the Resources I use

So if you want to do the C++ XLL journey, where do you start, and what do you need? I started by choosing the software I was going to install on my development system. Microsoft Visual Studio 2010 (C++ compiler … Continue reading

Posted in VBA, XLL | 2 Comments

Designing the SpeedTools function library – my VBA to C Journey part 1

This is the first of a series of posts about my perilous voyage from VBA to C++. I am starting with the (current) design of FastExcel V3 SpeedTools Beta 2 (bit of a mouthful so lets just call it SpeedTools). … Continue reading

Posted in Calculation, UDF, VBA, XLL | 5 Comments

COUNTA: When nothing becomes something, a cautionary tale

I was testing my FILTERIFS() function (returns a subset array of data filtered by multiple criteria, like COUNTIFS on steroids) when (thanks to my cunning regression test with conditional formatting that highlights the errors) I found that it was giving … Continue reading

Posted in UDF, VBA | Leave a comment

Sorting and Comparing the Excel Way: Code Pages and Collating Sequences – Revised

Comparing 2 values should be easy, but … Comparing values to see which is greater should be straightforward: you just use the less-than comparison operator: IF(A1<A2,TRUE,FALSE). So 1 is less than 2 and A is less than B. And when … Continue reading

Posted in Lookups, UDF, VBA, XLL | 4 Comments