how to make a nyquist plot by using frequency response vector ?

system is SISO, the frequency response vector in some frequency point is known (include abs,re,im). but the exactly FRF or TF is not known. in this condition, how to plot a nyquist curve? the matlab function 'nyquist' can plot nyquist only if there is a exactly TF. straightly plot the im & re, then

it is not smooth like a circle..