使用测试脚本,我发现系数小于1.5.我的代码看起来像：

tmco = {'NumHeaderLines', 1 , ...

'NumColumns' , 5 , ...

'ConvString' , '%f' , ...

'InfoLevel' , 0 , ...

'ReadMode' , 'block', ...

'ReplaceChar' , {',.'} } ;

A = txt2mat(filename, tmco{:});

注意不同的’ReplaceChar’值和’ReadMode”块’.

我在我的(不是太新的)机器上获得了大约5MB文件的以下结果：

> txt2mat test comma avg.时间：0.63231

> txt2mat test dot avg.时间：0.45715

> textscan test dot avg.时间：0.4787

我的测试脚本的完整代码：

%% generate sample files

fdot = 'C:\temp\cDot.txt';

fcom = 'C:\temp\cCom.txt';

c = 5; % # columns

r = 100000; % # rows

test = round(1e8*rand(r,c))/1e6;

tdot = sprintf([repmat('%f ', 1,c), '\r\n'], test.'); % '

tdot = ['a header line', char([13,10]), tdot];

tcom = strrep(tdot,'.',',');

% write dot file

fid = fopen(fdot,'w');

fprintf(fid, '%s', tdot);

fclose(fid);

% write comma file

fid = fopen(fcom,'w');

fprintf(fid, '%s', tcom);

fclose(fid);

disp('-----')

%% read back sample files with txt2mat and textscan

% txt2mat-options with comma decimal sep.

tmco = {'NumHeaderLines', 1 , ...

'NumColumns' , 5 , ...

'ConvString' , '%f' , ...

'InfoLevel' , 0 , ...

'ReadMode' , 'block', ...

'ReplaceChar' , {',.'} } ;

% txt2mat-options with dot decimal sep.

tmdo = {'NumHeaderLines', 1 , ...

'NumColumns' , 5 , ...

'ConvString' , '%f' , ...

'InfoLevel' , 0 , ...

'ReadMode' , 'block'} ;

% textscan-options

tsco = {'HeaderLines' , 1 , ...

'CollectOutput' , true } ;

A = txt2mat(fcom, tmco{:});

B = txt2mat(fdot, tmdo{:});

fid = fopen(fdot);

C = textscan(fid, repmat('%f',1,c) , tsco{:} );

fclose(fid);

C = C{1};

disp(['txt2mat test comma (1=Ok): ' num2str(isequal(A,test)) ])

disp(['txt2mat test dot (1=Ok): ' num2str(isequal(B,test)) ])

disp(['textscan test dot (1=Ok): ' num2str(isequal(C,test)) ])

disp('-----')

%% speed test

numTest = 20;

% A) txt2mat with comma

tic

for k = 1:numTest

A = txt2mat(fcom, tmco{:});

clear A

end

ttmc = toc;

disp(['txt2mat test comma avg. time: ' num2str(ttmc/numTest) ])

% B) txt2mat with dot

tic

for k = 1:numTest

B = txt2mat(fdot, tmdo{:});

clear B

end

ttmd = toc;

disp(['txt2mat test dot avg. time: ' num2str(ttmd/numTest) ])

% C) textscan with dot

tic

for k = 1:numTest

fid = fopen(fdot);

C = textscan(fid, repmat('%f',1,c) , tsco{:} );

fclose(fid);

C = C{1};

clear C

end

ttsc = toc;

disp(['textscan test dot avg. time: ' num2str(ttsc/numTest) ])

disp('-----')