Calculating Huge Numbers in Excel

  • Thread starter Thread starter StevieTNZ
  • Start date Start date
  • Tags Tags
    Calculations Excel
Click For Summary

Discussion Overview

The discussion revolves around the limitations of numerical calculations in Excel, specifically regarding the handling of very large numbers and the implications of significant figures in computational results. Participants explore the behavior of Excel when performing arithmetic with large integers and compare it to other software capabilities.

Discussion Character

  • Technical explanation, Debate/contested, Exploratory

Main Points Raised

  • One participant notes that Excel rounds off numbers beyond its precision limit, leading to the omission of smaller values in calculations with large integers.
  • Another participant cites that Excel is limited to 15 significant figures, which affects the outcome of calculations involving very large numbers.
  • Some participants suggest that other software, such as Computer Algebra Systems and certain programming languages, can handle large integers without losing precision.
  • There is a discussion about the computational power required for deep calculations, with one participant asserting that 64 bits is insufficient for high-precision arithmetic.
  • A suggestion is made to experiment with the order of operands in calculations to see if it affects precision, although this is met with skepticism regarding its impact on Excel's limitations.
  • Participants express differing views on whether changing the order of operands can help prevent loss of precision in specific cases.

Areas of Agreement / Disagreement

Participants generally agree that Excel has limitations in handling large numbers, but there is disagreement on the effectiveness of changing the order of operands to mitigate precision loss. The discussion remains unresolved regarding the specific impact of operand order in this context.

Contextual Notes

Limitations include the dependence on Excel's numeric precision and the varying capabilities of different software for handling large integers. The discussion does not resolve the implications of these limitations on specific calculations.

StevieTNZ
Messages
1,944
Reaction score
837
Hi there,

If I perform the following calculation in Excel:
=100,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000+50

I get: 100,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000

Shouldn't the answer be:
100,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,050?
 
Computer science news on Phys.org
No, the answer will be constrained by the number of bits used by the computer to represent the numbers, and you've got WAY more than it can handle, so the 50 gets dropped as a rounding error.
 
Is there any other program out there that will present the result given in my original post?
 
Lots of other programs can do that.
Computer Algebra Systems, like Mathematica, Sage, Maxima, Reduce, Maple... all do that.
http://en.wikipedia.org/wiki/Computer_algebra_system

Some calculator programs, like bc and many others do that.
https://www.google.com/search?q=big+integer+calculator&oq=big+integer+calculator

Many programming languages, like Icon, Java... do that, don't be fooled by those who think 64 bits is big.
https://www.google.com/search?q=programming+language+big+integer&oq=programming+language+big+integer
 
64 bits is chump change for deep calculations. You need a monster computer to process calculations beyond a few hundred decimal points. That is why numerical analysis takes so long and is so incredibly expensive.
 
Just for grins, try putting the smaller number first.
 
harborsparrow said:
Just for grins, try putting the smaller number first.

Do you really think that's going to have any effect on the fact that the larger number is WAY bigger than Excel can handle as an integer?
 
phinds said:
Do you really think that's going to have any effect on the fact that the larger number is WAY bigger than Excel can handle as an integer?

Sometimes it does help to prevent loss of precision by putting the smaller number first, when there is a huge range of magnitude difference between two operands.
 
  • #10
harborsparrow said:
Sometimes it does help to prevent loss of precision by putting the smaller number first, when there is a huge range of magnitude difference between two operands.

Yes, and that does not answer my question at all. I am asking about a specific case.
 

Similar threads

  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 19 ·
Replies
19
Views
4K
Replies
9
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 31 ·
2
Replies
31
Views
4K
  • · Replies 14 ·
Replies
14
Views
2K