how can i compute the length of an integer?

 采纳的回答

int=-123456789
max(ceil(log10(abs(int))),1)

1 个评论

this doesn't work for 10, 100, 1000...
for example max(ceil(log10(abs(10))),1) equals 1 but it should be 2
simple fix:
int = 10;
max(ceil(log10(abs(int)+1)),1)

请先登录,再进行评论。

更多回答(2 个)

Edit
nnz(num2str(int) - '-')

4 个评论

Why this cast to an double array? Shouldn't
numel(num2str(int))
be enough?
Friedrich, neither work actually, consider -12345.
Good point Sean. But then
numel(num2str(abs(int)))
should do ;)

请先登录,再进行评论。

Casting the variable into a string may be risky because you may get to "unexpected" cases such as:
int = 12345678901234567890123
numel(num2str(int))
ans =
12
You may consider a numeric approach using LOG10: floor(log10(int))+1 all numbers between 10 and 100 will have a LOG10 between 1 and 2 so you can use FLOOR to get the lower value (1 in this case) and then you need to add the value 1 cause you are trying to compute the number of digits and not the power of ten.

1 个评论

why, it works:
>> int = 12345678901234567890123
numel(num2str(int))
int =
1.2346e+22
ans =
23

请先登录,再进行评论。

类别

帮助中心File Exchange 中查找有关 Numeric Types 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