Abstract syntax: N elem-of Nml = binary numerals

    N ::= I F
    I ::= 0 | 1 | I0 | I1
    F ::= 0 | 1 | .0F | .1F

Semantic domain: Z = real numbers

Semantic function: Nm: Nml -> Z

    Nm[[IF]] = Nm[[I]] + Nm[[.F]]
    Nm[[I1]] = 2*Nm[[I]] + 1
    Nm[[I0]] = 2*Nm[[I]]
    Nm[[1]] = 1
    Nm[[0]] = 0
    Nm[[.1F]] = 1/2 + Nm[[.F]]/2
    Nm[[.0F]] = Nm[[.F]]/2
    Nm[[.1] = 1/2
    Nm[[.0] = 0

Test case: 1101.01
    Nm[[1101.01]] \kw= Nm[[1101]] + Nm[[.01]]
.ta \nwu
	= (2*Nm[[110]] + 1) + (Nm[[.1]]/2)
	= (2*(2*Nm[[11]]) + 1) + (Nm[[.1]]/2)
	= (2*(2*(2*Nm[1] + 1)) + 1) + (Nm[[.1]]/2)
	= (2*(2*(2*1 + 1)) + 1) + ((1/2)/2)