[Owyn]

PHP Code:

enum _:PosData
{
    Float:bd_pos[3],
    Float:bd_angles[3]
};

public init()
{
    new TempData[PosData];
    new Float:origin[3], Float:angles[3];
    TempData[bd_pos] = origin; // tag mismatch error
    TempData[bd_pos][0] = origin[0]; // must be an array error
} 


for strings I used copy() but what can I use for floats?

edit: I probably figured out i need to delcare TempData as a Float, is it because TempData only consists of Floats? if it consisted of a float and an integer I would need to declare it as usual without Float type?

[Arkshine]

is it because TempData only consists of Floats

It's because your members (bd_*) are floats and TempData would be a float too, same tag, no error.
It's fine to do it like that, if you have only floats as members.

if it consisted of a float and an integer I would need to declare it as usual without Float type

In case of others type then float, you have to cast the value.

new TempData[PosData];
new Float:origin[3];

TempData[bd_pos] = origin;

In this example, TempData is untagged, while origin is tagged with Float. That's why you have an error.
To remove the error, you have to untag origin, by doing either "_:origin" or "any:origin".
As note, you have only an error with strong tag (started by an upper-case letter). If origin was using a weak tag (started by an lower-case letter), the compiler casts implicitly the value.

[ConnorMcLeod]

Also, copy the 3 floats (3 vectors coords) 1 by 1.

[Arkshine]

No need and the problem would be still here.