Question about Excel and rounding off?

Question

When it comes to very large numbers, what does excel round the number at?
(e.g. for very small numbers, it is rounded down to zero).

For instance, when calculating the function (1+1/n)^n for increasing values of n, i get 2.718281 for a while but at one point and beyond it, I get 1.

What givessss?!

Answer 1

Excel calculates to a precision of 15 digits, the smallest number you can enter is 1.0 E-307. So it may be displayed as 0 but it is not rounded down to zero. The largest number you can enter is 9.999999999999999 E+307

If you increase the number of digits that are displayed, the numbers beyond the 15th digit will display as zeroes.

As for the function in question, as n goes to infinity the result goes to 1.

Answer 2

You do not say what values this is happening at but I guess it is going to be large values of n.

Excel has limitations, take a look for articles in the Microsoft knowledge base. Excel is limited to numbers numbers in the range of roughly 10^(-308) and 10^308. There are also problems with storing very small numbers as intermediate results in calculations and some errors can be introduced.

The knowledge base does make interesting reading and will give you an insight into the problems involved in performing calculations with very large or very small numbers and the sort of errors that can be introduced with some quite reasonable looking numbers. Some numbers that look nice and simple to the base 10 result in repeating, never ending patterns in binary which in the right circumstances can produce errors that you might not normally think of.

Answer 3

Yes, this actually happens and it's not because your decimal point is fixed wrong. It's because Excel has some limitations and can't compute this expression right for very large values of n. So, you must be vary careful when trying to determine limits using Excel.

Another example. For values of x very close to zero, Excel gives sin(x)/x = 0, which is obviously wrong since lim (x -> 0) sin (x)/x =1.

We should complain to Bill gates

Answer 4

Excel will round to whatever number you have asked it to using the ROUND equation (for instance, =round(a2,-3) will round a number to the thousands. If a number is large enough that it is giving you exponentials, resize the cell, change the cell formating to "numbers" or use the coma icon.
I was able to have this number show up fine in excell, are you dealing with anything bigger?

4,249,103,942,534,140,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000.00 x
the number is being cut off by yahoo

Answer 5

you are able to exchange this by potential of increasing the form of decimal places it reflects. it is going to be slightly button with an arrow to the superb and .00 and .0 all in the button. it rather is basically a default putting in specific circumstances. desire that helps :)

Answer 6

go to format cell and set the decimal point to however u like

Answer 7

Reset your decimal point.