Sysquake Pro – Table of Contents
Sysquake for LaTeX – Table of Contents
List Functions
apply
Function evaluation with arguments in lists.
Syntax
listout = apply(fun, listin) listout = apply(fun, listin, nargout) listout = apply(fun, listin, na) listout = apply(fun, listin, nargout, na)
Description
listout=apply(fun,listin) evaluates function fun with input arguments taken from the elements of list listin. Output arguments are grouped in list listout. Function fun is specified by either its name as a string, a function reference, or an anonymous or inline function.
The number of expected output arguments can be specified with an optional third input argument nargout. By default, the maximum number of output arguments is requested, up to 256; this limit exists to prevent functions with an unlimited number of output arguments, such as deal, from filling memory.
With a 4th argument na (or 3rd if nargout is not specified), named arguments can be provided as a structure.
Examples
apply(@size, {magic(3)}, 2)
{3, 3}
apply(@(x,y) 2*x+3*y, {5, 10})
{40}
The maximum number of output arguments of min is 2 (minimum value and its index):
apply(@min, {[8, 3, 4, 7]})
{3, 2}
Two equivalent ways of calling disp with a named argument fd to specify the standard error file descriptor 2:
disp(123, fd=2);
apply(@disp, {123}, 0, {fd=2});
See also
map, feval, inline, operator @, varargin, namedargin, varargout
join
List concatenation.
Syntax
list = join(l1, l2, ...)
Description
join(l1,l2,...) joins elements of lists l1, l2, etc. to make a larger list.
Examples
join({1,'a',2:5}, {4,2}, {{'xxx'}})
{1,'a',[2,3,4,5],4,2,{'xxx'}}
join()
{}
See also
operator ,, operator ;, replist
islist
Test for a list object.
Syntax
b = islist(obj)
Description
islist(obj) is true if the object obj is a list, false otherwise.
Examples
islist({1, 2, 'x'})
true
islist({})
true
islist([])
false
ischar('')
false
See also
isstruct, isnumeric, ischar, islogical, isempty
list2num
Conversion from list to numeric array.
Syntax
A = list2num(list)
Description
list2num(list) takes the elements of list, which must be numbers or arrays, and concatenates them on a row (along second dimension) as if they were placed inside brackets and separated with commas. Element sizes must be compatible.
Example
list2num({1, 2+3j, 4:6})
1 2+3j 4 5 6
See also
num2list, operator [], operator ,
map
Function evaluation for each element of a list
Syntax
(listout1,...) = map(fun, listin1, ...)
Description
map(fun,listin1,...) evaluates function fun successively for each corresponding elements of the remaining arguments, which must be lists or cell arrays. It returns the result(s) of the evaluation as list(s) or cell array(s) with the same size as inputs. Input lists which contain a single element are repeated to match other arguments if necessary. Function fun is specified by either its name as a string, a function reference, or an anonymous or inline function.
Examples
map('max', {[2,6,4], [7,-1], 1:100})
{6, 7, 100}
map(@(x) x+10, {3,7,16})
{13, 17, 26}
(nr, nc) = map(@size, {1,'abc',[4,7;3,4]})
nr =
{1,1,2}
nc =
{1,3,2}
s = map(@size, {1,'abc',[4,7;3,4]})
s =
{[1,1], [1,3], [2,2]}
map(@disp, {'hello', 'lme'})
hello
lme
Lists with single elements are expanded to match the size of other lists. The following example computes atan2(1,2) and atan2(1,3):
map(@atan2, {1}, {2,3})
{0.4636,0.3218}
See also
apply, cellfun, for, inline, operator @
num2list
Conversion from array to list.
Syntax
list = num2list(A) list = num2list(A, dim)
Description
num2list(A) creates a list with the elements of non-cell array A.
num2list(A,dim) cuts array A along dimension dim and creates a list with the result.
Examples
num2list(1:5)
{1, 2, 3, 4, 5}
num2list([1,2;3,4])
{1, 2, 3, 4}
num2list([1, 2; 3, 4], 1)
{[1, 2], [3, 4]}
num2list([1, 2; 3, 4], 2)
{[1; 3], [2; 4]}
See also
replist
Replicate a list.
Syntax
listout = replist(listin, n)
Description
replist(listin,n) makes a new list by concatenating n copies of list listin.
Example
replist({1, 'abc'}, 3)
{1,'abc',1,'abc',1,'abc'}