Kotlin: Number Type and Range

I summarized Kotlin basic number types and their range. In Kotlin, we can use Byte, Short, Int, Long, and UByte, UShort, UInt, ULong.

Size in Memory

Here, bit width and byte width for each number type.

Here is the ranges of their values.

Zeal number can take 2^{(bit width)} numbers. Float, Double are calculated as below.

Float, Double is separated into 3 part, sign part, exponent part, and fraction part in memory. The bit width of them are as follows.

The value is expressed with the 3 values. Exponent value can be less than 0.

Now, denote the 3 parts as follows.

Notation
(s)	Sign part value (0 or 1)
(e_b)	Bit width of exponent part (8 for `Float`, 11 for `Double`)
(e)	Exponent value in binary expression (from 0 to (2^{e_b} – 1))
(f_b)	Bit width of fraction part (23 for `Float`, 54 for `Double`)
(f)	Fraction value in binary expression (from 0 to (2^{f_b} – 1))

Then, the value of Float or Double can be written as follows.

[ (-1)^s times 2 ^ { e – 2 ^ { e_b – 1 } } times left( 1 + frac{f}{2^ {left( f_b + 1 right)} } right) ]

The value is the maximum when (s=0,e=2^{e_b}-1,f=2^{f_b}-1).

Here are some examples of sign, exponent and fraction parts in Float.