fix bug where np.nan value for lat_n, lat_s etc. would overwrite a pre-existing value
fix bug where np.nan value for lat_n, lat_s etc. would overwrite a pre-existing value
Caoimhinmg/PmagPy,lfairchild/PmagPy,Caoimhinmg/PmagPy,Caoimhinmg/PmagPy,lfairchild/PmagPy,lfairchild/PmagPy