[MadeMan]

numargs shows the number of arguments
getarg gets the argument value
setarg sets the argument value

If you have a function like

pawn Код:

SetPlayerData(playerid, ...)

and you call it like this

pawn Код:

new number = 789;
SetPlayerData(playerid, 45, 1235, number);

numargs() is 4
getarg(0) is playerid
getarg(1) is 45
getarg(2) is 1235
getarg(3) is 789 (because number = 789)
setarg(3, 0, 123) sets 'number' to 123

There is also an example on the wiki

https://sampwiki.blast.hk/wiki/ResetPlayerWeaponsEx