sizeof

Calc Software Package for Number Calc

NAME
    sizeof - number of bytes required for value

SYNOPSIS
    sizeof(x)

TYPES
    x		any

    return	integer

DESCRIPTION
    This is analogous to the C operator sizeof for the value only.
    It attempts to assess the number of bytes in memory used to store
    a value and all of its components.	Unlike memsize(x), this
    builtin does not include the size of the overhead.

    Unlike size(x), this builtin incldues the trailing \0 byte on the
    end of strings.

    For numeric values, sizeof(x) ignores the demoninator if 'x' is
    an integer.	 For complex values, sizeof(x) ignores the imaginary
    part if 'x' is real.  Because the 0, 1 and -1 numeric values are
    shared static values, sizeof(x) reports such values as having
    0 bytes of storage.

    The number returned by sizeof(x) may be less than the actual number
    used because, for example, more memory may have been allocated for
    a string than is used: only the characters up to and including the
    first '\0' are counted in calculating the contribution of the
    string to sizeof(x).

    The number returned by sizeof(x) may be greater (and indeed
    substantially greater) than the number of bytes actually used.
    For example, after:

		a = sqrt(2);
		mat A[3] = {a, a, a};

    the numerical information for a, A[0], A[1], A[2] are stored in the
    same memory, so the memory used for A is the same as if
    its 3 elements were null values.  The value returned by
    sizeof(A) is calculated as A were defined by:

		mat A[3] = {sqrt(2), sqrt(2), sqrt(2)}.

    Similar sharing of memory occurs with literal strings.

    For associative arrays, only the value part of the name/value pair
    is counted.

    The minimum value for sizeof(x) occurs for the null and error values.

EXAMPLES
    The results for examples like these will depend to some extent on
    the system being used.  The following were for an SGI R4k machine
    in 32-bit mode:

    ; print sizeof(null()), sizeof(0), sizeof(3), sizeof(2^32 - 1), sizeof(2^32)
    8 68 68 68 72

    ; x = sqrt(2, 1e-100); print sizeof(x), sizeof(num(x)), sizeof(den(x))
    148 108 108

    ; print sizeof(list()), sizeof(list(1)), sizeof(list(1,2))
    28 104 180

    ; print sizeof(list()),sizeof(list(1)),sizeof(list(1,2)),sizeof(list(1,2,3))
    28 104 180 256

    ; mat A[] = {1}; mat B[] = {1,2}; mat C[] = {1,2,3}; mat D[100,100];
    ; print sizeof(A), sizeof(B), sizeof(C), sizeof(D)
    124 192 260 680056

    ; obj point {x,y,z}
    ; obj point P = {1,2,3}; print sizeof(P)
    274

LIMITS
    It is assumed sizeof(x) will fit into a system long integer.

LINK LIBRARY
    none

SEE ALSO
    size, fsize, strlen, digits

## Copyright (C) 1999  Landon Curt Noll
##
## Calc is open software; you can redistribute it and/or modify it under
## the terms of the version 2.1 of the GNU Lesser General Public License
## as published by the Free Software Foundation.
##
## Calc is distributed in the hope that it will be useful, but WITHOUT
## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
## or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU Lesser General
## Public License for more details.
##
## A copy of version 2.1 of the GNU Lesser General Public License is
## distributed with calc under the filename COPYING-LGPL.  You should have
## received a copy with calc; if not, write to Free Software Foundation, Inc.
## 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
##
## @(#) $Revision: 29.3 $
## @(#) $Id: sizeof,v 29.3 2006/05/07 07:25:46 chongo Exp $
## @(#) $Source: /usr/local/src/cmd/calc/help/RCS/sizeof,v $
##
## Under source code control:	1996/05/24 02:04:04
## File existed as early as:	1996
##
## chongo <was here> /\oo/\	http://www.isthe.com/chongo/
## Share and enjoy!  :-)	http://www.isthe.com/chongo/tech/comp/calc/