formula field with value from other field

aridzv
aridzv
in 2D Drafting

Hi.
in AutoCAD, i had a file block of a bolt,block of washer and a block of a nut, all of them have an attribute of quantity.
in the the quantity attribute of washer i have a formula that multiple the value of the quantity attribute of the bolt by 2.
the formula in autocad looks like this: %<\AcExpr (%<_FldPtr 2308284037632>%*2)>%
and "FldPtr 2308284037632" is probably a pointer to the bolt quantity attribute' that this is its full name : %<\AcObjProp Object(%<_ObjId 2273144859872>%).TextString>% '
and in bricscad, in the object field i do get this expression, but it doesn't allow for mathematical functions.
is there a way to create formula in the formula field?
i found the formula field in the attribute but it doesn't accept any formula containing link to other fields.
Thanks,
Ari.