How to use the small positive float number?

3 次查看（过去 30 天）
Mahdiyar
Mahdiyar 2015-5-15
编辑： Guillaume 2015-5-15
Hi everyone
I am writing the code in which I need to deal with quite small number like
A = (1/2^8)^512
When I run this line, matlab gives back 0 as the results. However, I need this number to be multiplied with other big numbers.
How can I save the real value of variable A?
Many thanks,
Regards

请先登录，再回答此问题。

回答（1 个）

Guillaume
Guillaume 2015-5-15
编辑：Guillaume 2015-5-15
In plain matlab, you cannot represent such a number as it's way outside the range that a double can represent. The exponent part of a double is 11 bits, offset by 1023, so the minimum number that can be represented by a double is around 2^-1023 (the true minimum is 2^-1074), your number is 2^-4096!
You would have to use vpa from the Symbolic math toolbox (I know nothing about it, I don't have it), or go through Java's BigDecimal, or look through the file exchange for an arbitrary precision type.

类别

在 Help Center 和 File Exchange 中查找有关 Logical 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