爲matlabs編寫包裝保存功能

Question

我會（在我的情況，以便保存大文件的預定義version），即像這樣

save('parameters.mat', 'some', 'parameters', 'here', '-v.3'); 

應該轉向寫與預定義選項MATLAB的save功能的包裝這個

save_large('parameters.mat', 'some', 'parameters', 'here'); 

其中save_large是save的包裝與version設置爲'-v7.3'：

function [ ] = save_large(filename, varargin) 
%varargin to allow for multiple variable storing? 

%what to write here to save all variables (declared as chars) stored in 
%the workspace where 'save_large' was called with version set to '-v7.3'? 

end 

Answer 1

因爲變量將不會在功能save_large的範圍存在，你將不得不使用evalin從"caller"工作區得到變量。

使用try我們也可以確保變量在調用者工作區中存在。

爲了讓您的.mat文件中正確的變量名，我們既可以使用（鼓勵）eval功能，或者分配所有的變量的結構下面的方法，然後用-struct標誌save。

function save_large(filename, varargin) 
    % Set up struct for saving 
    savestruct = struct(); 
    for n = 1:numel(varargin) 
     % Test if variable exists in caller workspace 
     % Do this by trying to assign to struct 
     % Use parentheses for creating field equal to string from varargin 
     try savestruct.(varargin{n}) = evalin('caller', varargin{n}); 
      % Successful assignment to struct, no action needed 
     catch 
      warning(['Could not find variable: ', varargin{n}]); 
     end 
    end 
    save(filename, '-struct', 'savestruct', '-v7.3'); 
end 

---

例

% Create dummy variables and save them 
a = magic(3); 
b = 'abc'; 
save_large test.mat a b; 
% Clear workspace to get rid of a and b 
clear a b 
exist a var % false 
exist b var % false 
% Load from file 
load test.mat 
% a and b in workspace 
exist a var % true 
exist b var % true