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Release calc version 2.12.0

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Landon Curt Noll
2006-05-21 01:11:18 -07:00
parent 7165fa17c7
commit 58d94b08d8
342 changed files with 8845 additions and 6327 deletions
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help/modify
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@@ -2,29 +2,43 @@ NAME
modify - modify a list or matrix by changing the values of its elements
SYNOPSIS
modify(x, y)
modify(A, fname)
TYPES
x lvalue with list or matrix value
y string
A lvalue with list, matrix or objectvalue
fname string, the name of a user-defined function
return null value
return null value if successful, otherwise an error 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]]).
The value of each element of A is replaced by the value at that
value of the user-defined function with name fname. Thus,
modify(A, "f") has the effect of
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).
for (i = 0; i < size(A); i++) A[[i]] = f(A[[i]]);
An error value is returned if A is not of acceptable type, if A has
no-change protection, or if there is no user-defined function with
name fname. The assignments are executed even if the protection
status of some elements A[[i]] would normally prevent the
assignment of f(A[[i]]) to A[[i]]. The modified elements retain
whatever kinds of protection they had as well as gaining any
other kinds of protection in the values returned by the function.
To obtain a modified copy of A without changing values in A,
one may use
Amod = A; modify(A, fname)
or more simply
modify(Amod = A, fname).
EXAMPLE
> define f(x) = x^2
> A = list(2,4,6)
> modify(A, "f")
> print A
; define f(x) = x^2
; A = list(2,4,6)
; modify(A, "f")
; print A
list (3 elements, 3 nonzero):
[[0]] = 4
@@ -56,8 +70,8 @@ SEE ALSO
## received a copy with calc; if not, write to Free Software Foundation, Inc.
## 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
##
## @(#) $Revision: 29.2 $
## @(#) $Id: modify,v 29.2 2000/06/07 14:02:33 chongo Exp $
## @(#) $Revision: 29.4 $
## @(#) $Id: modify,v 29.4 2006/05/19 15:12:57 chongo Exp $
## @(#) $Source: /usr/local/src/cmd/calc/help/RCS/modify,v $
##
## Under source code control: 1995/07/10 02:09:31