I appreciate what you did. However, what I didn't fully explain is that the 3 fields are joined in the downstream application. These values are used to label plots, and the plots are sorted either as strings or numbers (the application works like Perl in this sense). Some plots are displayed side by side, so a progression of temperature or voltage from left to right or top to bottom is very helpful.

If I had the choice of sorting it myself, it would be easy. Instead, I have to make the strings sort as numbers, by fudging the strings.