function matlab_types
% For a list of datatypes, type 'help class'


% Most variables are created as type 'double'

%% BASICS

a = 3
class(a)

% An array is treated as whatever data type is inside, in this case double
disp_type( 3:7 )

% function handle
disp_type( @matlab_types )

% cell array
disp_type( cell(2,2) )

% strings are arrays of characters
b = 'MATLAB rules'
disp( b(8:end) )
disp_type( b )

% Changing the type of an object rarely causes a warning
% This means you should be careful about overwriting data!
a = 3:20               % No warning, you probably meant to do this
a.best_field = 'hello' % MATLAB thinks you probably didn't want to do this
disp_type( a )


%% CELL ARRAYS

% Cell arrays are multidimensional arrays that hold arbitrary data
a = cell(2) % EQUIVALENT: a{2,2} = [];
a{1,1} = 'Character array'; 
a{1,2}.new_field = 'awesome';
a{2,1} = [1 2; 3 4];
a{2,2} = a

%% STRUCT ARRAYS

clear a 
a(3).height = 20; % Preallocation is specifying the largest element first
a(1).weight = 30;
a(1).name = 'tim';

isfield(a, 'age')
isfield(a, 'height')

a(2).name = 'alex';
a(3).name = 2; % A different type from a(1).name; it's allowed, but be careful

a(3).name = 'jasmin'
[a(3)] % Use brackets to pull information from fields across the struct array
{a(3)} % Or use braces to get the across-struct field in a cell array

% Multidimensional struct arrays are allowed, just like arrays and cell arrays
a(3,2,2,2).height = 25;




%%
function disp_type(a)
% This function can't normally be accessed from outside the m_file

class_a = class(a);

header = '%%------%%';
disp(sprintf('%s\rData is:', header)) % sprintf behaves somewhat like its C 
disp(a)                               % analog
disp( sprintf('Type is:\r    %s\r\r', class_a) )