How to generate one random integer
44 次查看(过去 30 天)
显示 更早的评论
I need to generate one random integer.
I tried these codes:
X = randi(1)
X = rand(1)
However, it only gives random numbers between 0 and 1 (like 0.2567, 0.9432, etc.).
I am hoping to get a random number from negative infinity to positive infinity.
What function should I use to be able to generate one random integer?
Thanks in advance!
5 个评论
David
2024-1-28
Right, I agree that isinteger is testing that a value is a member of the "integer class", but if randi purports to produce pseudo-random integers, then shouldn't results me members of the interger class without explaicitly declaring that they are; i.e., without the need for the "int16" declaration. (I guess not, and I appreciate your response, but if a function says it is returning an integer, then in my book, it should actually return an integer that tests "true" for being a member of that class. That's why I think this is confusing.
Dyuman Joshi
2024-1-28
There's a difference between the integer as a data type and integer as a numerical entity.
The function randi() does return an integer, but, by default, it is of class double.
采纳的回答
更多回答(1 个)
Walter Roberson
2020-7-3
编辑:Walter Roberson
2024-1-28
The following generates integers natively.
typecast(randi([0 255],1,8,'uint8'),'int64')
The range is all possible integers between -2^63 and +2^63-1
infinity cannot be generated with this setup, as infinity is not part of the integer system.
To generate integers outside of the range indicated above, you need to switch to double(), but if you do that, you only have 53 bits of precision available, and all values outside the range +/- 2^53 are integers that are multiplied by a power of 2 -- you could not, for example, generate 2^53 + 17 . By 1E50, adjacent representable values are 2^114 apart. Is that what you want to deal with?
另请参阅
类别
在 Help Center 和 File Exchange 中查找有关 Logical 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!