On Tue, 13 Nov 2007 17:40:04 +0000 (UTC), Tom wrote:

I have a large vector of values with a wide dynamic range (10^-6 to 10^-
16). For a particular application, I need to retrieve only the first
digits of the values, yielding an output vector that contains only the
values 1 through 9. I can do this manually fairly easily by first
multiplying by an appropriate value to bring the result to a whole number,
then truncating the fractional part.

I'm sure that there must be a way to automate this in Excel, but I can't
figure out how to do it. The problem seems to lie in my inability to
separate the characteristic and mantissa.

Any ideas?


--Tom

=LEFT(TEXT(A1,"0.000000000000000E+0"),1)

Note that if in the TEXT function, you have fewer digits in the decimal
portion, some values may be rounded up in the first digit.
--ron