Best way to initialize a fractional fixed point value.

[joaomontenegro]

What's the best way to initialize a uint256 with a fractional number?

Pseudocode of an example of what I am trying to achieve:
uint256 x = 0.123;

[PaulRBerg]

Hey! There are multiple ways to do this, as there is a multitude of conversion function shipped with PRBmath.

Scientific Notation

// 0.5
UD60x18 foo = ud(0.5e18);
UD60x18 foo = ud60x18(0.5e18);
UD60x18 foo = wrap(0.5e18);

"To" Conversion Function

This only works for whole numbers greater than or equal to 1e18. See the NatSpec comments for the toUD60x18 for more details on how this works.

// 50
UD60x18 foo = toUD60x18(50);