August 2018
Intermediate to advanced
227 pages
4h 16m
Chinese
Content preview from 高效R语言编程
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高效硬件
｜
167
当计算机科学家刚考虑计算机内存时，他们注意到
2
10
= 1024 ≈ 10
3
与
2
20
=
1048576 ≈ 10
6
,
所以他们采用了
kilo-
与
megabytes
的简写。当然，每个人明白，
这仅仅是一个缩写，事实上它是二进制的幂。当计算机被广泛使用，一般的
非专业人士才会认为
kilo
就表示
10
3
字节。
幸运的是，
IEEE
标准委员会干预并创造了常规的、使用
SI
（国际单位制）前
缀的国际上通用的定义。
所以一个
kilobyte
（
kB
）是
10
3
= 1000
字节，一个
megabyte
（
MB
）是
10
6
bytes
或者
10
3
kilobytes
（见表
8-2
）。一个
petabye
大致相当于装满
100
兆个抽屉的文字数量。令人吃惊的是，
Google
每天大约
处理
20 Petabytes
的数据。
表
8
-
2
：数据单位名称转换表，来源 : http://physics.nist.gov/cuu/Units/binary.html
二进制计量
名字
符号
原用名
推导
2
10
kibi Ki Kilobinary: (2
10
)
10
2
20
mebi Mi Megabinary: (2
10
)
2
2
30
gibi Gi Gigabinary: (2
10
)
3
2
40
tebi Ti Terabinary: (2
10
)
4
2
50
pebi Pi Petabinary: (2
10
)
5
尽管对内存容量的标准达成了一致
,
但不是所有人都遵从它，例如，微软的
Windows
系统中， ...
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I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.