Category:Rounding

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This category contains results about Rounding.
Definitions specific to this category can be found in Definitions/Rounding.


Rounding is the process of approximation of a value of a variable to a multiple of a given power of whatever number base one is working in (usually decimal).


Let $n \in \Z$ be an integer.

Let $x \in \R$ be a real number.


Let $y \in \R$ such that:

$y = 10^n \floor {\dfrac x {10^n} + \dfrac 1 2}$

or:

$y = 10^n \ceiling {\dfrac x {10^n} - \dfrac 1 2}$

where $\floor {\, \cdot \,}$ denotes the floor function and $\ceiling {\, \cdot \,}$ denotes the ceiling function.


Then $y$ is defined as $x$ rounded to the nearest $n$th power of $10$.


Both of these definitions amount to the same thing, except for when $\dfrac x {10^n}$ is exactly halfway between $\floor {\dfrac x {10^n} }$ and $\ceiling {\dfrac x {10^n} }$.

How these instances is treated is known as the treatment of the half.