text:       FUNCTION evlmem(fdt,d,m,xms)
        INTEGER m
        REAL evlmem,fdt,xms,d(m)
        INTEGER i
        REAL sumi,sumr
        DOUBLE PRECISION theta,wi,wpi,wpr,wr,wtemp
        theta=6.28318530717959d0*fdt
        wpr=cos(theta)
        wpi=sin(theta)
        wr=1.d0
        wi=0.d0
        sumr=1.
        sumi=0.
        do 11 i=1,m
          wtemp=wr
          wr=wr*wpr-wi*wpi
          wi=wi*wpr+wtemp*wpi
          sumr=sumr-d(i)*sngl(wr)
          sumi=sumi-d(i)*sngl(wi)
  11    continue
        evlmem=xms/(sumr**2+sumi**2)
        return
        END
  