matlab | sscanf faster than str2double

trFolder = 'data\mmm\SH600519T';
trFiles = dir(fullfile(trFolder, 'trade*2013013*.csv'));
tr1D =read1csv(fullfile(trFolder, trFiles(1).name));
tic
for i=1:length(tr1D.textdata(:,4))
tt=tr1D.textdata(i,4);
dummy = sscanf(tt{:}, '%f');
end
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tic
str2double(tr1D.textdata(:,4));
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