Symbols · Notation and constants
⌊x⌋ ⌈x⌉ Floor and ceiling
Say it: “the floor of x”, “the ceiling of x”
What it means
The floor rounds down to the nearest whole number; the ceiling rounds up. So ⌊2.7⌋ = 2 and ⌈2.1⌉ = 3.
Read aloud in real formulas
⌈log₂ n⌉
Aethel says
the ceiling of log base 2 of n
the number of bits to count to n, rounded up
Typing it
- LaTeX
- \lfloor x \rfloor, \lceil x \rceil
- Unicode
- U+230A, U+230B, U+2308, U+2309
Questions
How do you say ⌊x⌋ out loud?
It is usually read “the floor of x”, and also “the ceiling of x”.
What does ⌊x⌋ mean in maths?
The floor rounds down to the nearest whole number; the ceiling rounds up. So ⌊2.7⌋ = 2 and ⌈2.1⌉ = 3.
How do you type ⌊x⌋?
In LaTeX, write \lfloor x \rfloor, \lceil x \rceil. Its Unicode code point is U+230A, U+230B, U+2308, U+2309.