list - Scilab object and list function definition

Calling Sequence

list(a1,....an)

Description

Creates a list with elements ai 's which are arbitrary Scilab objects ( matrix, list,... ). Type of list objects is 15. list() creates the empty list (0 element).

Operations on lists

extraction : [x,y,z...]=L(v) where v is a vector of indices; [x,y,z]=L(:) extracts all the elements.

insertion at index i : L(i)=a (note that it is not an error to use L(i)=a with i > 1 + size(L) but some list entries are then undefined and their extraction gives raise to an error).

append an element in queue : L($+1)=e.

append an element in head : L(0)=e. (note that after this operation e is at index 1, the initial elements being shifted on the right).

deletion : L(i)=null() removes the i-th element of the list L.

concatenation of two lists : L3 = lstcat(L1,L2).

number of elements of a list : you can use either nb_elm = size(L) or nb_elm = length(L).

iterations with a list : it is possible to use a list L with a for loop: for e=L,...,end is a loop with length(L) iterations, the loop variable e being equal to L(i) at the i th iteration.

Remarks

Scilab provides also other kinds of list, the tlist type (typed list) and the mlist type which are useful to define a new data type with operator overloading facilities ( hypermatrices which are multi-dimensionnal arrays in scilab are in fact mlist).

Matlab struct are also available.

Examples

l = list(1,["a" "b"])
l(0) = "foo"
l($+1) = "hello"
l(2) = "toto"
l(3) = rand(1,2)
l(3) = null()
lbis = list("gewurtz", "caipirina" ,"debug")
lter = lstcat(l,lbis)
size(lter) - size(lbis) - size(l)  // must be zero

See Also

null ,   lstcat ,   tlist ,   insertion ,   extraction ,   size ,   length ,