Thread: Time Accuracy
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joeu2004 joeu2004 is offline
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Default Time Accuracy

On Mar 16, 2:25 pm, I wrote:
On Mar 16, 1:30 pm, Bill Sharpe wrote:
Do the math and you'll see that you won't get any
closer accuracy than tenths of a second.

[....]
Nonetheless, your conclusion is correct.


Sorry, I misread. Your conclusion is incorrect. The Excel NOW()
function is accurate to 10 milliseconds. That is hundredths of a
second.


----- original posting -----

On Mar 16, 2:25*pm, joeu2004 wrote:
On Mar 16, 1:30*pm, Bill Sharpe wrote:

Chip Pearson has an explanation of how Excel stores
dates and times at
http://www.cpearson.com/excel/datetime.htm.
There are six digits set aside to store 24 hours of time.
Do the math and you'll see that you won't get any closer
accuracy than tenths of a second.


Exactly how did you "do the math"?

First, Chip's description of the internal format is over-simplified
and frankly incorrect to the degree that you interpreted it (literally
6 digits "set aside" for time).

Second, even if we assume there are 6 digits for time, I do not see
how to "do the math" to reach the conclusion that you did. *(Hint:
Try entering =0.01/86400 and format it as Number. *How many decimal
places do you need?)

Nonetheless, your conclusion is correct.