NAME
    modify - modify a list or matrix by changing the values of its elements

SYNOPSIS
    modify(x, y)

TYPES
    x		lvalue with list or matrix value
    y		string

    return	null value

DESCRIPTION
    For modify(x, y), y is to be the name fname of a user-defined function.
    The value of each element of x is replaced by the value of the
    function at that value, i.e.  if fname = "f", the value of x[[i]]
    is changed to f(x[[i]]).

    As the name indicates, modify(x) usually changes x values of elements
    in x.  To obtain a modified copy of x without changing values in x,
    one may xmod = x; modify(xmod, y) or more simply (xmod = x, y).

EXAMPLE
    > define f(x) = x^2
    > A = list(2,4,6)
    > modify(A, "f")
    > print A

    list (3 elements, 3 nonzero):
	  [[0]] = 4
	  [[1]] = 16
	  [[3]] = 36

LIMITS
    none

LIBRARY
    none

SEE ALSO
    makelist
