Simple calculation problem that involves scientific notation

[EinarRoed]

I've got two source tables. Both contain a numeric variable called SUM. I'll call them SUM_A and SUM_B.

SUM_A can sometimes be displayed using a scientific notation. SUM_B is always displayed as a plain number.

I need to add SUM_A to SUM_B. I've made the new variable SUM_TOTAL (format: comma20.) which uses this expression: SUM_A + SUM_B

When SUM_A uses a scientific notation, then the end result is always equal to SUM_B. Example:

How can I make SUM_TOTAL display SUM_A + SUM_B?

[PaigeMiller · Accepted solution]

Try format BEST20.

[Kurt_Bremser]

And when adding very small numbers to considerably large numbers, you will run into the limits of numeric precision. Keep in mind that only 15 to 16 decimal digits can be stored reliably in 8-byte real.