# A just out of curiosity question re @DiskTotal

#### mathewsdw

As always, an example:
Code:
``````[Z:\]Echo %@Comma[%@Eval[%@DiskTotal[C:,k]+%@DiskTotal[D:,k]+%@DiskTotal[E:,k]]]
491,514,744

[Z:\]Echo %@Comma[%@Eval[%@DiskTotal[C:,m]+%@DiskTotal[D:,m]+%@DiskTotal[E:,m]]]
491,513``````
The question is, of course, how there can be fewer megabytes than kilobytes, particularly when the the number of kilobytes has the value that it has ...m744]? What am I missing here?

#### samintz

##### Scott Mintz
Most likely it's due to truncation error. Display the individual disk totals, then the sum and see if it's different.
Code:
``````Echo %@DiskTotal[C:,kc] %@DiskTotal[D:,kc] %@DiskTotal[E:,kc]  %@Comma[%@Eval[%@DiskTotal[C:,k]+%@DiskTotal[D:,k]+%@DiskTotal[E:,k]]]
Echo %@DiskTotal[C:,mc] %@DiskTotal[D:,mc] %@DiskTotal[E:,mc]  %@Comma[%@Eval[%@DiskTotal[C:,m]+%@DiskTotal[D:,m]+%@DiskTotal[E:,m]]]``````

#### TEA-Time

Probably because of rounding?

#### mathewsdw

Guys, I found the problem. You see, the function truncates any fractional value so the 321987k becomes 321m and it is the sum of those three what would be fractional megabyte values that goes up to the next megabyte in the kilobyte measurements and those fractional values for megabytes are discarded.

#### Steve Fabian

You want true values - use b. You can adjust the total if desired.

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