reading text data with textscan annoyingly slow

[MarcelK]

http://octave.1599824.n4.nabble.com/file/n3972499/example1.ncf example1.ncf 

Hi,

I'm using Octave 3.2.4. with Windows XP. (i686-pc-mingw32)
I'm also using GUIOctave 1.5.3. as frontend. 

I'm facing some problems reading data from a .ncf text file.
I've attached an example of such a file (I hope that worked).
It takes about 60 seconds to read one single ncf file 
However, in Matlab it takes not even a second.

Here's my code I use to read the data in:


function [Date1,headlines,nummatrix] = ncfread (filename)

fid=fopen(filename,'r'); 

%# read data headers  
headerdata=fgets(fid);
index=findstr(headerdata,'}');
ncols=length(index); 
headlines={};
headlines(1)=headerdata(1:index(1));
for mm=2:ncols
          headlines(mm)=headerdata(index(mm-1)+1:index(mm));
endfor

textformat=['%s %s',repmat('%f',1,ncols-2)];

datacell=textscan(fid,textformat);

Date1=datacell{1,1}{1};


timedata=datacell{2};

fclose(fid);

%# generate time vector (time in hours)
t=zeros(size(datacell,1),1);
timestring=char(timedata);
for jj=1:size(timestring,1)
    tstruct=strptime(timestring(jj,:),'%R');
          t(jj)=tstruct.hour+tstruct.min/60;
endfor

%# conversion cell>matrix
nummatrix=zeros(length(datacell{1}),size(datacell,2));
nummatrix(:,2)=t;

for ii=3:size(nummatrix,2)
        nummatrix(:,ii)=datacell{ii};
endfor

nummatrix(:,1)=[];

endfunction


My way of converting the "time string" (e.g. '10:00')  to time in hours
(e.g. 10.00) seems quite complicated to me, is there maybe a better way to
achieve this?


Thanks in advance,

Marcel

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