C+
C NAME:
C	midpnt_inc
C PROCEDURE:
C	Common part of the Mid* functions used in nrQRomo
C-
        if (N .eq. 1) then
            S = (B-A)*Func(0.5*(A+B))
            IT = 1
        else
            TNM = IT
            DEL = (B-A)/(3.*TNM)
            DDEL = DEL+DEL
            X = A+0.5*DEL
            SUM = 0.
            do J=1,IT
                SUM = SUM+Func(X)
                X = X+DDEL
                SUM = SUM+Func(X)
                X = X+ DEL
            end do
            S = (S+(B-A)*SUM/TNM)/3.
            IT = 3*IT
        end if