The vector scope tool is displayed when a stereo input is detected, otherwise the display will switch to Surround scope provided if your edition of Pure Analyzer includes this option.
Vector scope display in stereo.
Vector scope display in surround (with selection menu).
Use only Left and Right Channels.
Use a stereo down mix with all front channels.
Use a stereo down mix with all Rear channels.
Use a stereo down mix with all channels.
Use a Lt/Rt down mix with all channels.
Use a mono summation of Left and Right + the Lfe (sub) channel.
Use Center + Lfe (sub) channel.
Use a mono summation of the front channels + the Lfe (sub) channel.