How to teleport based on the custom data of a marker entity

How do i do something like this that works:
Tick function:
data modify storage macro coords set value {"x":0.0,"y":0.0,"z":0.0}
execute store result storage macro coords.x double 1 run execute on passengers run data get entity @s data.xvel
execute store result storage macro coords.y double 1 run execute on passengers run data get entity @s data.yvel
execute store result storage macro coords.z double 1 run execute on passengers run data get entity @s data.zvel
function datapack:move with storage macro coords
Info:
I have a block display with a marker riding it.
The block display executes the function.
Move function:
$tp @s ~$(x) ~$(y) ~$(z)
Error:
It only works with non-decimal numbers.