error in large integers

1 次查看（过去 30 天）
Eigo Takkeda
Eigo Takkeda 2012-3-21
I am currently working with fractions involving 10digit integers.
for example, typing 1168347147/863334886 into MATLAB produces the answer 4045/2989.
But I want to store the fractions exactly. How do I go about doing this?
Many thanks.

请先登录，再回答此问题。

回答（2 个）

Aldin
Aldin 2012-3-21
Hi,
use vpa functon
for example:
vpa('4045/2989',100) ---> for hundred digits
  5 个评论
显示 3更早的评论
Aldin
Aldin 2012-3-22
I think is more better to use smaller number like 4045/2989 ???
Aldin
Aldin 2012-3-22
Do you know:
1168347147/863334886 = 4045/2989

请先登录，再进行评论。

Walter Roberson
Walter Roberson 2012-3-22
If you have the symbolic math toolbox, then
sym('1168347147/863334886')
Note that the result will be a symbolic number, not a double precision number.
  3 个评论
显示 1更早的评论
Walter Roberson
Walter Roberson 2012-3-22
Yes, if you do have the symbolic toolbox then you would be able to use symbolic numbers in further calculations; the results would be symbolic numbers.
There might be places along the way where you needed to convert the symbolic numbers to double precision using double(), as there are MATLAB routines that cannot work with symbolic numbers.
Aldin
Aldin 2012-3-22
Hello sir Walter,
Can you please explain:
>> sym('1168347147/863334886')
ans =
1168347147/863334886
>> ans * 1,4
ans =
8178430029/4316674430
--------------------------
But if i check last result with 'vpa' function i got this:
>> vpa('863334886*1,4)
ans = 1208668840.4

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Numbers and Precision 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by