Frequently Asked Questions

Erlang for Excel

Will Erlang for Excel work with Excel 2010 on Windows 7?

Yes, use the Excel 97 version. Copy the Erlang97.xla file to C:\Users\[user name]\App Data\Roaming\Microsoft\AddIns\ErlangXL97.xla. (Note the App Data folder is normally hidden, in Windows Explorer go to Organise - Folder & Search Options - View and set the option to 'Show hidden files, folders and drives').
To enable the Add-in, from the menu choose File - Options - Add-Ins - Manager - Browse. Navigate to the folder that contains Erlang.xla and select. Then when the Addin has been loaded ensure that the tickbox next to Erlang for Excel is ticked.

Will Erlang for Excel work with Excel 2007?

Yes, use the Excel 97 version. Copy the Erlang97.xla file to C:\Documents and Settings\[user name]\Application Data\Microsoft\AddIns\ErlangXL97.xla. To enable the Add-in, click on the Office button in the top left hand corner of the window. Then choose Excel Options, Add-Ins is an option down the left of the form. Select Excel Add-Ins in the drop-down and click GO. Tick the box next to Erlang for Excel (if not shown use Browse to find the .xla file).

Will Erlang for Excel work with Excel 2000?

Yes, use the Excel 97 version. Copy the Erlang97.xla file to C:\Windows\Application Data\Microsoft\AddIns.

Will Erlang for Excel work with Excel XP/2002?

Yes, use the Excel 97 version. The default location for XP is C:\Documents and Settings\[user name]\Application Data\Microsoft\AddIns\ErlangXL97.xla If you use this location it means that you have to store the addin in each user's profile (if more than one person uses the PC)

I get an error when I try to load the add-in.

This is usually due to file corruption during the download. Try the download again. Try opening ErlangExample97.xls, if you get an error complaining that the file has "..links to an external workbook" you have not installed the Add-in properly. Follow the instructions in ErlangInstall.txt.

My call volumes are in half hour periods, can the code be modified to accept half-hour volumes?

Simply multiply the call volumes by 2 within Excel. It will give the correct answers as the Erlang model works on traffic intensity, it does not matter whether this is measured by the hour or the half-hour.
 E.g. =Agents(0.95,15,($B$2 * 2),$B$3).

How can I send my spreadsheet to a colleague who does not have the add-in?

Find the file ErlangXL97Source.xls, this is a distributable version of the add-in. Build your sheets in the normal way in this workbook and 'save as' under a different name. You can send this file to anyone without the add-in having to be loaded.

I get a zero answer even with large call volumes

Check the input to the formula, all functions return a zero if they encounter an error. Don't forget that percent figures are entered as decimal, e.g. 95% as 0.95, and all times as seconds.

Is Erlang for Excel Year 2000 compliant?

Yes, although Erlang uses measures of time these time periods are not relative to any year.


Can I use TheSwitch to forecast the number of agents required?

No, a simulator can only confirm the performance that will be achieved with a number of agents.

Will TheSwitch work for non skill based routing simulations?

Yes, you can simulate a traditional queue/agent group simply by setting the vector routing type to "Any Agent" or "Longest Idle".

What type of skill based routing is used in the simulation?

The simulator is loosely based on the Avaya Definity implementation of skill based routing which is agent focused. Calls are assigned to any agent with the correct skill level.

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