Category Archives: Excel

Only Calculating the Active Workbook

Posted on March 1, 2023 by fastexcel

When you have more than one workbook open Excel has always recalculated all of the workbooks at each recalculation. That can be very painful if one or more of the workbooks are slow to calculate. Now the Excel Dev Team … Continue reading →

Posted in Calculation, Excel | Tagged | Leave a comment

Short-circuiting in Array Formulas

Posted on January 6, 2023 by fastexcel

The previous post demonstrated that IF and CHOOSE short-circuit but IFS and SWITCH do not. But following up a hint from Bill Wu that IF behaves differently in array formulas I decided to check whether it still short-circuits.(IF in array … Continue reading →

Posted in arrays, Calculation, Dynamic Arrays, Excel, UDF | Tagged | 3 Comments

Short-circuiting Excel Formulas: IF, CHOOSE, IFS and SWITCH

Posted on January 3, 2023 by fastexcel

What is formula short-circuiting? Short-circuiting occurs in Excel formulas when an IF statement only evaluates the True part of the IF and skips the False part of the IF. For example in this formula: Because 1>2 evaluates to False the … Continue reading →

Posted in Calculation, Excel | Tagged , , | 3 Comments

FastExcel Version 4 – with Introductory Offer

Posted on February 5, 2020 by fastexcel

After several man-years of development and a lot of beta testing FastExcel Version 4 has finally hit general availability! FastExcel V4 is a major rewrite of FastExcel V3 and provides many of the things you have been asking for: Support … Continue reading →

Posted in arrays, Calculation, Debug formulas, Dynamic Arrays, Excel, Lookups, Memory, UDF, VBA | Leave a comment

Backward Compatibility of Office 365 Dynamic Arrays (Updated 23 Sep 2020)

Posted on May 20, 2019 by fastexcel

Office 365 Excel Dynamic Arrays are great, but: What happens when you create a workbook with Dynamic Array  Excel (Excel DA) and send it to someone who does not have Excel DA, and how do you write VBA code that … Continue reading →

Posted in arrays, Dynamic Arrays, Excel, Uncategorized, VBA | Tagged | 21 Comments

Develop Excel Conference

Posted on July 30, 2018 by fastexcel

The Develop Excel conference will take place in London on Thursday October the 18th 2018. It will be held at the Microsoft Reactor (70 Wilson Street London EC2A 2DB). Are you responsible for building Excel based Addins and Solutions? Develop … Continue reading →

Posted in .NET, arrays, Excel, JS-API, UDF, VBA, XLL | 2 Comments

Strategies for getting the last row in Excel with VBA

Posted on September 1, 2017 by fastexcel

Using VBA to get the last row in Excel can be a surprisingly complex task. This post will explore some of the different strategies you can use. The first thing to do is to decide what you mean by “The … Continue reading →

Posted in Excel, Formatting, VBA | Tagged , | 10 Comments

Excel JavaScript API Part 5: The large numbers bug

Posted on April 5, 2017 by fastexcel

There is currently (JavaScript Excel API set 1.4) a rather nasty bug when writing large integer numbers (anything larger than int32) back to a range. 30 January 2018 – API set 1.7 – this bug is still there! The JS … Continue reading →

Posted in Excel, JS-API | Tagged , | 4 Comments

Excel JavaScript API Part 4: The shallow copy problem

Posted on April 5, 2017 by fastexcel

I was trying to read the values from a Range and then write modified versions of the values to two different ranges. Should be straightforward: Well this does not work: both B4 and B6 have 0.91 added to them: wrong … Continue reading →

Posted in arrays, Excel, JS-API | Tagged , | 1 Comment