recvar.m

阵列信号处理的工具箱

% *****************************************************************************
% RECVAR, A package for new data types in Matlab. 
% (c) FOA 1998. See the file rvright.m for copyright notice.
%
% 	Record variables in RECVAR
% 	--------------------------
%
% A record variable (called a strucure in Matlab 5) enables the collection
% of different Matlab variables that belong to each other in one unit,
% a record variable. This concept is usual in programming languages like
% Pascal (record) and C/C++ (struct/class) and data bases but did not exist
% in Matlab prior to version 5.
%
% A "record variable" consists of one or more "fields". For example
% a record variable 'person1' with the fields 'name' and 'age':
%
%	>> person1 = setr([],'name','Tom');
%	>> person1 = setr(person1,'age',35);
%
% Now one can handle the 'person1' with all its fields as one unit.
% One can get, for example, the age by:
%
%	>> getr(person1,'age')
%
%	     ans =
%		   35
% 
%
% The following functions are currently implemented:
%
%	setr	: Creates record variables and creates and changes the 
%		  contents of fields.
%	getr	: Gets the contents of fields.
%	showr   : Prints the contents of all fields in a record variable
%		  on the screen. Similar to typing the name of a normal Matlab
%                 variable without a semicolon.
%	whosr	: Like 'whos' but for the fields in a record variable.
%	recdir  : Returns a Matlab matrix with the names of all fields
%		  in a record variable.
%	existr	: Returns true if the specified field exists in the record 
%		  variable.
%	isrecvar: Returns true if the argument is a record variable.
%	versionr: Returns version info. about the package for record variables.
%
%	tmatvar	: A testprogram for testing this package.
%	
% For more information about the functions use 'help' for the corresponding 
% function.
%
%Matlab 4:
%---------
% Allowed operation on record variables is: 
%   assignment '=' of a whole record variable.
% It is possible to use record variables as function parameters and as 
% function return values. Making any other operation except for the functions 
% below on a record variabl may lead to unpredictable results, including a 
% system crash.
% 
% Fields can be real or complex full Matlab matrices and Matlab strings.
% The possibility to have sparse matrices as fields is not implemented.
%
% It is possible to use 'save' and 'load' directly with record variables 
% on a fixed computer system. It is, however, recommended to pick out the 
% fields with 'getr' and then save the field variables instead of the 
% record variable. This because matrices may be represented in other 
% ways on other computer systems or in other releases of Matlab. 
% With different matrix
% representations for 'save' and 'load', the contents in a record variable 
% will be corrupted and that may lead to unpredictable results, including
% a system crash.
%
% Currently it is not possible to remove a field entirely but this possibility
% is planned. Today you can minimize the field size by assigning it an 
% empty matrix [].
%
%Matlab 5:
%---------
% Record variables are implemented using Matlab 5's structures, see [1].
%
%Other data structures in RECVAR:
%--------------------------------
% Use 'help multimat' for information about  multidimentional matrices, 
% "multimatrices", (i.e. with more than two indices.).
% Use 'help listhelp' for information about the data structure "list".
%
%References:
% [1] "Using Matlab Version 5", The MathWorks, Inc., 1997. 
% *****************************************************************************

%  Start        : 95xxxx Svante Bj鰎klund (svabj).
%  Latest change: $Date: 1998/05/12 10:42:08 $ $Author: svabj $.
%  $Revision: 2.7 $
% *****************************************************************************