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 Writing Efficient VBA UDFs (Part13): MaxMinFair Resource Allocation – an array UDF example
 Excel Circular References: Calculation, Detection, Control and Removal
 Excel ForceFullCalculation: Trading off Editing speed vs Calculation speed
 Timing Excel Formula Calculations
 2014 in review
 Stacking (Appending) Arrays/Ranges in Excel: Formulas versus Functions Shootout
 Using Constant Arrays and Array Expressions in Excel Formulas
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Category Archives: Calculation
Writing Efficient VBA UDFs (Part13): MaxMinFair Resource Allocation – an array UDF example
Last year we got to spend a great day at Microsoft Research in Cambridge (UK). one presentation was about storage strategies and featured (amongst other stuff) an interesting algorithm called MaxMinFair. The MaxMinFair algorithm You can read about it here … Continue reading
Excel Circular References: Calculation, Detection, Control and Removal
Circular references in Excel are generally bad news: They are slow to calculate They can be hard to detect An intentional circular reference can mask an unintended circular reference, They do not always converge The Status Bar always shows calculate … Continue reading
Posted in Calculation
Tagged calculation methods, Circular References, Excel, Excel Formulas
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Excel ForceFullCalculation: Trading off Editing speed vs Calculation speed
A recent post at Stack Overflow reminded me that I have not posted about the pros and cons of Excel’s Workbook.ForceFullCalculation property. So what does Workbook.ForceFullCalculation do? The simple answer is that it switches off Excel’s smart recalculation algorithm, so … Continue reading
Timing Excel Formula Calculations
I have written a couple of posts previously about the methodology of timing Excel calculations: A Quantum of Time – measuring time accurately The XIPS Challenge – how fast does Excel calculate? But rather than focus exclusively on how to … Continue reading
Posted in Calculation, Uncategorized
Tagged calculation methods, calculation speed, Excel 2013 benchmark, Excel Formulas
1 Comment
Stacking (Appending) Arrays/Ranges in Excel: Formulas versus Functions Shootout
This post is a follow up to my last post Using Constant Arrays and Expressions in Excel Formulas. I will explore how some of the general purpose arrayhandling functions in FastExcel SpeedTools Extras compare with formulas using native Excel functions. … Continue reading
Posted in arrays, Calculation, Lookups, Uncategorized, XLL
Tagged array constant, array expression, array function, Arrays, calculation speed, Excel Formulas, Excel functions, XLL
4 Comments
Calling XLAM/XLL/Automation UDFs from VBA: Evaluate, Run, or Reference?
I have this nagging feeling that I do not know the best way to call UDFs from VBA. So after a couple of days of research here is what I have found out so far. The Available Methods Application.ExecuteExcel4Macro This … Continue reading
Posted in Calculation, UDF, VBA, XLL
Tagged array formula, array function, calculation speed, UDF, XLL
4 Comments
Timing the Ins and Outs of User Defined Functions: MultiCell array formulas can be slow
I was looking at some multicell array formula UDFs with John and Rich and could not understand why they seemed so much slower than I expected. Each UDF (written as C++ XLLs) read data from around 200 cells using around … Continue reading
Posted in Calculation, UDF, Uncategorized, VBA, XLL
Tagged array formula, array function, calculation speed, Excel 2010 Calculation Bug, UDF, XLL
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Getting Used Range in an XLL UDF: Multithreading and COM
In two previous blog posts I discussed why handling wholecolumn references efficiently in VBA UDFs meant that you had to find the used range for the worksheet containing the wholecolumn reference. The posts also discussed how using a cache for … Continue reading
FastExcel V3 Released with Introductory Offer
FastExcel has been used successfully by thousands of users since it was first launched in 2001. The last version 2.4 was introduced in 2008 and since that time there have been major changes to Excel with Excel 2007, 2010 and 2013, … Continue reading
Posted in Calculation, Lookups, Memory, UDF, VBA, XLL
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