! :folding=indent:collapseFolds=0:

! $Id$
!
! Copyright (C) 2003, 2004 Slava Pestov.
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IN: math
USE: lists
USE: math
USE: stack

: |+ ( list -- sum )
    #! sum all elements in a list.
    0 swap [ + ] each ;

: +| ( list list -- list )
    [ + ] 2map ;

: |* ( list -- sum )
    #! multiply all elements in a list.
    1 swap [ * ] each ;

: *| ( list list -- list )
    [ * ] 2map ;

: *|+ ( list list -- dot )
    #! Dot product
    *| |+ ;

: average ( list -- avg )
    dup |+ swap length / ;