Spot operator: opSubsAsgn Spot Home Page
opSubsAsgn
 opSubsAsgn   Redefine rectangular subset of operator.
 
    opSubsAsign(A,ROWIDX,COLIDX,B), index = ':' is valid. Size of B
    must match that of rowidx and colidx. THe indices can exceed the
    size of A (even if idx is given as logical) but must not be negative?
See also