I have just published a new tool today, Trusted Document Manager. This little tool enables you to manage your list of trusted documents. Currently, Excel only allows you to either leave the list intact, or delete the entire list. This means all of your currently trusted documents become untrusted again so you have to enable macro’s on all of them once again. The tool allows you to remove just one file, remove an entire folder or even an entire drive. Also it offers to possibility to remove files which no longer exist from the list.
A common requirement is to generate a set of random numbers that meet some underlying criterion. For example, a set of numbers that are uniformly distributed from 1 to 100. Alternatively, one might want random numbers from some other distribution such as a standard normal distribution.
While there are specialized algorithms to generate random numbers from specific distributions, a common approach relies on generating uniform random numbers and then using the inverse function of the desired distribution. For example, to generate a random number from a standard normal distribution, use =NORM.S.INV(RAND())
Another common requirement is the generation of integer random numbers from a uniform distribution. This might be to select people for something like, say, training, or a drug test. Or, it might be to pick a winner for a door prize at a social event. It might also be to assign players to groups for a sport tournament such as golf.
By default, Excel has a limited number of charts. That does not mean that those are the only charts one can create. It turns out that with a little imagination and creativity, we can format and configure the default charts so that the effect is like many other kinds of charts.
One of the more versatile of charts is the XY Scatter chart. We can use it as the base for many data visualization tasks. Recently, for a client, I used one to create a radial org chart as in Figure 1. Such a chart is also called a Node-Link chart or a Reingold–Tilford Tree.
Figure 1 – Example of a radial org graph created in an Excel XY Scatter chart
after removal of all identifiable information and the obfuscation of data
necessary to protect the client’s confidentiality.
A lot of “out of the box” work into making this chart. One key element was the set of equidistant concentric circles that provide a visual reference for the small colored dots. This note demonstrates how to create concentric circles in an Excel XY Scatter chart.
I got a email from a client asking for help because Excel was “destroying,” to use his terminology, his 2003 workbook after conversion to the 2007 format. And, after analyzing the kind of change Excel made, I had to agree.
The following in 2003
becomes, in 2013 (and in 2010),
The basic problem is that names that are legitimate names in Excel 2003 may become unacceptable in 2007 (or later). But, a more devastating problem is with a formula using a name with a dot in it. Even though it is completely legitimate, Excel changes the dot to a colon. This causes the formula =SW1.SW2 to become =SW1:SW2. Don’t ask me why. It just does. The result is the formula is all wrong and destroys the integrity of the workbook.
It appears that the cause may be Excel trying to help manage the transition of a XLS workbook into the newer format. In 2007, Microsoft increased the number of columns from 256 to 16,384. Consequently, the reference to last column went from IV to XFD. So, a name such as SW1, completely OK in 2003, became unacceptable in 2007. On converting a XLS file to a XLSX file, Excel will convert such names by adding an underscore at the start of the name. But, it seems to go beyond that, converting formula references to certain names with dots in them to a colon. This happens if both the tokens to the left and to the right of the dot could be legitimate cell references. So, Excel converts the formula =XFD1.XFD2 to =XFD1:XFD2 but it will leave =XFD1.XFE2 alone.
To replicate the problem:
Start with Excel 2003. Create a workbook and add the names shown in the Figure 1. Save and close the workbook.
Open the workbook in Excel 2013. Save it as a XLSX file. Acknowledge the warning message (see Figure 3),
Close and reopen the new XLSX workbook. The formulas will have the errors shown in Figure 2.
The safest way to work around this problem is to add an underscore before every name in the workbook before making the transition to the 2007 format. Obviously, the quickest way to do this would be with a very simple VBA procedure. But, through trial and error I discovered the code will not work in 2003. It runs without any problems but it doesn’t do anything!
So, the correct way to use the code is the following sequence.
Open the XLS file in 2013 (or 2010).
Run the macro below.
Now, save the file in the newer format. If your original workbook had no code in it, save the file as a XLSX file and acknowledge the warning that the VB project will be lost.
Close and reopen the file. You should see the correct data with all the names now starting with an underscore.
TM Goal Seek enhances the existing user interface to Excel’s Goal Seek feature. The built in Goal Seek is a simple optimization tool that suffices for a large number of scenarios. The UI, unfortunately, is extremely unwieldy and unfriendly. TM Goal Seek is a simple add-in that is easier to use than the default dialog box because of three critical benefits:
The target value can be a number or a reference to a cell that contains a number,
The add-in retains values previously entered in the dialog box, and
One can interact with the worksheet even with the dialog box open.
The motivation to develop the add-in came from work I was doing for a client who managed gambling sites not on gamstop that involved risk analysis on multiple investment scenarios of financial derivative trades. The default Goal Seek interface took way too long.
The current version of the add-in will expire on May 1, 2013.
Two things that could be better about the Range.Find method have been 1) up-to-date and correct documentation, and 2) adding the UI’s ‘Find All’ capability to the Excel Object Model. As of Office 2013 neither has happened.
Consequently, every time I want to use the Find method, I continue to have to jump through hoops to figure out the correct values for the different arguments.
I also discovered that FindNext does not work as expected when one wants to search for cells that meet certain format criteria. Consequently, I updated my long available FindAll function so that it works correctly with format criteria.