Search

Recent Posts
 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
 Calling XLAM/XLL/Automation UDFs from VBA: Evaluate, Run, or Reference?
 Once inalifetime Bordeaux wine Tasting: This time we made it!
 2014 MVP Summit
 Timing the Ins and Outs of User Defined Functions: MultiCell array formulas can be slow
 Automatic or Manual Calculation?: Grouped Sheets causes Calculation Confusion.
Recent Comments
Post Archive
 May 2015 (2)
 February 2015 (1)
 January 2015 (2)
 December 2014 (1)
 November 2014 (2)
 October 2014 (3)
 September 2014 (2)
 August 2014 (2)
 June 2014 (1)
 April 2014 (1)
 February 2014 (1)
 January 2014 (3)
 December 2013 (2)
 November 2013 (4)
 October 2013 (6)
 September 2013 (4)
 February 2013 (3)
 January 2013 (3)
 December 2012 (4)
 November 2012 (2)
 October 2012 (2)
 September 2012 (1)
 July 2012 (6)
 June 2012 (7)
 April 2012 (1)
 March 2012 (2)
 February 2012 (1)
 January 2012 (3)
 December 2011 (1)
 November 2011 (3)
 October 2011 (2)
 September 2011 (2)
 August 2011 (1)
 July 2011 (4)
 June 2011 (8)
 May 2011 (4)
Categories
Blogroll
RSS
Blog Stats
 346,216 hits
 Follow Excel and UDF Performance Stuff on WordPress.com
Category Archives: Calculation
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
Leave a comment
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
Leave a comment
Threading and HyperThreading: Optimizing Excel Calculation speed by changing the number of threads
I have just implemented measuring multithreaded calculation efficiency in FastExcel V3 Profile Workbook: so I thought it would be interesting to see the effect on calculation speed of varying the number of threads, and switching off hyperthreading. Hyperthreading Almost all … Continue reading
Excel 2013 SDI Bug: “Calculate” in Status Bar strikes again
In the old days (I’m talking Excel 5 to Excel 2003 here) there was a worrying situation you could find yourself in where, no matter what you did, Excel would show you “Calculate” in the statusbar. Even when actually nothing … Continue reading
Posted in Calculation, VBA
6 Comments