How do I pull avatar from post using BuddyPress? [closed]

Try this:

$author_id = get_the_author_meta('ID');
echo bp_core_fetch_avatar ( array( 'item_id' => $author_id, 'type' => 'full' ) ); 

Defaults:

array(
   'item_id'    => false,
   'object'     => 'user',
   'type'       => 'thumb',
   'avatar_dir' => false,
   'width'      => false,
   'height'     => false,
   'class'      => 'avatar',
   'css_id'     => false,
   'alt'        => '',
   'email'      => false,
   'no_grav'    => false,
   'html'       => true,
   'title'      => '',
);