varspace() returns the number of bytes allocated to each variable specified by
its name or directly provided. When an heterogenous container like a list, a
cells array or a structure is provided, the vector or matrix of numbers of bytes
allocated to their components is returned.
varspace() will be useful to optimize algorithms using a lot of intermediate
memory, or simply to get aware about memory consumption w.r.t. to data types and
sizes.
Help page, examples and results follow.
--> varspace
Memory space taken by specified variables, litterals, or containers components
CALLING SEQUENCES
-----------------
varspace // displays this help
varspace var1 var2 ...
vm = varspace("var1", "var2", ...)
Vm = varspace(VarNames)
Vm = varspace(obj#1)
VM = varspace(obj#1, obj#2, ...)
PARAMETERS
----------
var1, var2,.. :
Words = names of variables that's memory space must be
returned or displayed.
VarNames :
Vector or matrix of non-empty words = variables names
vm : Row of decimal numbers = memory space allocated to associated
variables, in bytes.
Vm : Vector or matrix of decimal numbers, having the size of
VarNames or obj#1.
Vm(i) = memory allocated to the variable named VarNames(i)
or to the component obj#1(i).
Vm(i,j) = memory allocated to the variable named VarNames(i,j)
or to the component obj#1(i,j).
obj#1, obj#2,.. :
Literal objects, or variables of simple data type, or
heterogeneous containers (Lists, Cells arrays, Structures
arrays). If a component C is itself a container, varspace()
is not recursively applied to its components: Only its whole
varspace is returned at the C position.
VM : List of vectors or matrices of decimal numbers.
VM(i) has the size of obj#i. It provides the vector or matrix
of numbers of bytes allocated to the components of obj#i:
- literal objects or expressions: the object or the result
of the expression is first assigned to a temporary variable.
The memory space taken by this one is returned.
- words or texts (scalar, vector or matrix): are considered
as objects in their own, not as names of variables to be
byte-sized.
DESCRIPTION
-----------
For a series of scilab variables, varspace() returns the respective
amounts of allocated memory, in bytes.
If a queried variable or a component of a list or stucture does
not exist, a memory amount == -1 is returned.
NOTE: Only local variables are seen. To make a global variable locally
visible, please apply global() to it before calling varspace().
NOTE: If two variables with the same name are defined in the local
and the global spaces and are queried, only the local one is
considered.
EXAMPLES
--------
clear d
a = 1, b = [1 2], c = [1 2 3], e = [], es = '', s1 = 'a', s2 = 'ab'
ec = cell(); ec22 = cell(2,2); ec44 = cell(4,4); ec88 = cell(8,8);
// Specifying names of variables
// -----------------------------
varspace ec ec22 ec44 ec88 // inline syntax (then without coma)
varspace('a,b ,c, d, e,es, s1,s2, ec22 ec88, a')
varspace(['a' 'b' 'c' ; 'd' 'ec' 'a']) // matrix of variables names
// Specifying objects
// ------------------
// Matrix of texts considered as an object (because '' can't be the name
// of a variable) :
varspace(['a' 'b' 'c' ; 'd' 'e' ''])
// Containers like a cells array: the memory allocated to each array's
// component is returned:
c = makecell([2,3], %t,%pi,%z, list('hello',rand(3,5)),'',rand(1,3)<0.5)
// The memory allocated to the cell is greater than the sum of
// memory allocated to its components:
varspace(c)
sum(varspace(c)), varspace("c")
// This is also the case for lists, that can have undefined components:
m = rand(100,100);
L = list(m, m+%i*m, , m<0.5, int8(m), int16(m), int32(m));
varspace('m', L) // Since L is an object, 'm' is considered
// as a simple string (another object),
// instead of a variable's name
// To get the varspace of a litteral string, you may embed it in a list:
varspace(list("a,b ,c, d, e,es, s1,s2, ec22 ec88, a"))
// .. or priorly assign it to a variable:
s = "a,b ,c, d, e,es, s1,s2, ec22 ec88, a";
varspace s
SEE ALSO:
* who : http://help.scilab.org/docs/current/en_US/who.html
* http://wiki.scilab.org/Memory%20representation%20of%20variables
RESULTS OF EXAMPLES
===================
--> clear d // d does no longer exist
--> a = 1; b = [1 2]; c = [1 2 3]; e = []; es = ''; s1 = 'a'; s2 = 'ab';
--> ec = cell(); ec22 = cell(2,2); ec44 = cell(4,4); ec88 = cell(8,8);
-->
--> // Specifying names of variables
--> // -----------------------------
--> varspace ec ec22 ec44 ec88
ans =
160. 240. 480. 1440.
--> varspace('a,b ,c, d, e,es, s1,s2, ec22 ec88, a')
ans =
16. 32. 40. - 1. 16. 32. 32. 32. 240. 1440. 16.
--> varspace(['a' 'b' 'c' ; 'd' 'ec' 'a'])
ans =
16. 32. 40.
- 1. 160. 16.
-->// Specifying objects
-->// ------------------
--> varspace(['a' 'b' 'c' ; 'd' 'e' ''])
ans =
64.
--> c=makecell([2,3],%t,%pi,%z,list('hello',rand(3,5)),'',rand(1,3)<0.5)
c =
!%t 3.1415927 z !
! !
!{2 list} "" [%f,%t,%f] !
--> varspace(c)
ans =
24. 24. 56.
208. 32. 24.
--> sum(varspace(c)), varspace("c")
ans =
368.
ans =
552.
--> m = rand(100,100);
--> L = list(m, m+%i*m, , m<0.5, int8(m), int16(m), int32(m));
--> varspace('m', L)
ans =
ans(1)
32.
ans(2)
80016. 160016. - 1. 40016. 10024. 20024. 40024.
