Monthly Archives: July 2011

Developing Faster Lookups – Part 2 – How to build a faster VBA Lookup

In part 1 I looked at some of the difficulties with making efficient use of Excel’s built-in Lookup and Match functions: Lookups are often recalculated unecessarily even when all data actually relevant to the Lookup is unchanged. Binary Search Lookup … Continue reading

Posted in Calculation, UDF, VBA | 20 Comments

Developing Faster Lookups – Part 1 – Using Excel’s functions efficiently – updated

When profiling Excel workbook calculation time I often find that Lookups are one of the main causes of performance problems. So this is the first of 2 posts looking at how to do Lookups faster. This post concentrates on the … Continue reading

Posted in Calculation, Lookups | 10 Comments

Excel UDF Technology Choices – Snakes & ladders with VBA, VB6, .NET, C++, COM, XLL, Interop …

I develop a commercial Excel addin product, FastExcel, one component of which contains a number of UDFs. I have been planning and developing the next version of FastExcel for some time, and it probably won’t surprise you to hear that … Continue reading

Posted in .NET, UDF, VBA, XLL | 21 Comments

Making the most of your XIPS (Part 1) – counting XIPS and reducing them to make Excel calculate faster

In the previous post The Xips challenge – How fast does Excel Calculate I managed to make Excel calculate 6.6 million simple formulae in under a second, and promised to come back in future posts to try to answer my … Continue reading

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