[Cueball]

You need to pass arrays to the function, which contain your co-ordinates (your "XYZ" (though with this function, there is no Z-axis evaluation)):

pawn Код:

new Float:PointA[2] =
{
  // X, Y of Point A. For Example:
  123.45, 678.90
},
  Float:PointB[2] = 
{
  // X, Y of Point B. For Example:
  987.65, 432.10
};

new Float:angle = Angle2D(PointA, PointB);

OR

pawn Код:

new Float:angle = Angle2D({ 123.45, 678.90 }, { 987.65, 432.10 }); // PointA, PointB.

Just use that kind of syntax, and you're in business

~Cueball~