On 5/7/2018 2:14 AM, GS wrote:
Actually, your example isn't textual dates; - they're numeric! This is
where the problem lies. A2 in my exercise is an example of textual date
format; - it doesn't matter what the system format is because that
format will ALWAYS display correctly.

It seems like the text ' confused Excel and my little-used Excel
"skills" led me down the primrose path...I forgot that 5/5 isn't
interpreted as division if don't use the preceding '=' so was trying too
hard to force interpretation as date.

Using just 5/6 or whatever does get interpreted correctly and one can
use a custom format of d/m/yy _or_ m/d/yy OK and mix them; all is well
after all...sorry for my miscue on the data entry.

The point still is, though, that your example all starts with the date
form being known a priori and all the example does is use a
non-ambiguous visual format to display the content.

There still is no way to determine which of two ambiguous date forms
from another system _AS THE TEXT DATE STRING_ is which from the string
format alone; and it still isn't totally clear for OP's problem after
the explanation whether he has the required information at the point
he's trying to solve the problem or not.

What I've discovered is that you can still manually force the cell
format to interpret the external input correctly by applying the
appropriate format but the initial input will be interpreted based on
the system setting. I'm used to being able to use MATLAB input forms in
which I can specifically define that the input format is what I want
irrespective of the system settings.

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