Method of functional equivalents in the theory of angular momentum

The method is proposed by means of which certain operations over $c$-number functions can be put into correspondence with operations over the fuctions of noncommuting angular momentum operators. With the aid of projection operators, the rule ofl calculating the traces in the subspace of spin / is formulated in functional terms. Functional equivalents of the most widely used operators are found. Relations between atomic coherent states of different types are discussed.