Javascript 整数与浮点 memory - 小数位数是否会影响 memory？

Question

Have some svg files with many points, running lots of calculations on these values...trying to optimize calculations and memory:

Floating Point values store twice as much memory as integers:

// 5 is less memory than 5.6789

What about within Floating Point values - do fewer decimal places require less memory?

// Does 5.12 require less memory than 5.12341234647839234798372938719 ?

EDIT: removed PI and replaced with generic random number.

Answer 1

The Number type is double-precision 64-bit IEEE 754 binary floating point. All values (from 5 to 5.12341234647839234798372938719) occupy the same amount of memory (eight raw bytes of memory, with possible overhead from object wrapping, depending on engine), but precision is limited; the literal 5.12341234647839234798372938719 is expressing false precision (eg 5.12341234647839234798372938718 is the same value).