Explode cell that are into another cell
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I have a cellarray data like in the picture : each cell contains cellarray of strings
I am opening all all the cells with this way
counter=0;
for ind=1:length(data)
tmp=cell2str(data{ind,1});
for k=1:size(tmp,1)
counter=counter+1;
tmp2=textscan(tmp(k,:),'%s%s%s%s%s%[^\n\r]','Delimiter', ' ');
for j=1:6
if isempty(tmp2{j})==0
Raw(counter,j)=tmp2{j};
end
end
clear tmp2 j
end
clear k tmp
end
The results is correct but is there a better/faster way to do it ?
Using parfor, or other technics
Thank you in advance
9 Comments
dpb
on 9 Jan 2019
Well, no...helping would be to show us what you really, really want instead of just describing it that we can't reproduce.
Where did you find the function? SHOW us!!!
Accepted Answer
Jan
on 9 Jan 2019
Start with a pre-allocation:
Len = cellfun('prodofsize', data);
Raw = cell(sum(Len), 6);
c = 0;
for ind = 1:numel(data)
tmp = data{ind};
for k = 1:numel(tmp)
c = c + 1;
tmp2 = strsplit(tmp{k}, ' ');
for j = 1:numel(tmp2)
Raw{c, j} = tmp2{j};
end
end
end
I cannot open your MAT file currently, so I guess, what it might contain. I guessed also, that cell2str can be avoided by scanning the cell element directly. I assume that Raw should be a cell array. All these assumptions can be wrong. If you post a small input as code and the wanted output, less guessing is required.
5 Comments
More Answers (2)
dpb
on 9 Jan 2019
Edited: dpb
on 9 Jan 2019
OK, I overlooked the regular expression in the format string that sucks up all of those extra blanks at the end of the odd-man-out records...
To dereference the cell content in each cell requires two levels snce textscan isn't cell-string aware. split doesn't cut it here because there's not a unique delimiter that defines the fields desired; hence the above...
You can try the following and see if the lack of preallocation shows up as a performance hit with the size; oftentimes it'll fool you and not be too bad...
fnTS=@(s) textscan(s,'%s%s%s%s%s%[^\n\r]','Delimiter', ' ');
res=[];
for i=1:length(data)
res=[res;cellfun(fnTS,data{i},'uni',0)];
end
res=cat(1,res{:});
The above yields a 64x6 cell array...
I'd have to think of the bestest way to be able to build the array directly w/o the intermediary second cell array to not be dynamically catenating the output.
ADDENDUM:
res(cellfun(@isempty,res))={''};
>> string(res)
ans =
11×6 string array
"1" "EventDataLogNewFile" "DataEventTime" "TypeSecondsSinceEpoch" "1546725641" ""
"1" "EventDataLogNewFile" "DataEventTime" "TypeFormattedDate" "Sun" "Jan 6 00:00:41 2019"
"1" "EventDataLogNewFile" "DataReportingSubsystem" "TypeString" "datalogger" ""
"1" "EventDataLogNewFile" "DataInstrumentID" "TypeString" "00:01:05:19:CF:30" ""
"1" "EventDataLogNewFile" "DataEntityName" "TypeString" "mc16" ""
"4" "EventREAD" "DataEventTime" "TypeSecondsSinceEpoch" "1546725657" ""
"4" "EventREAD" "DataEventTime" "TypeFormattedDate" "Sun" "Jan 6 00:00:57 2019"
"4" "EventREAD" "DataReportingSubsystem" "TypeString" "pc" ""
"4" "EventREAD" "DataEntityID" "TypeString" "Dev_CLPC_PressureGauge1" ""
"4" "EventREAD" "DataReading" "TypeUnitLessNumber" "34729" ""
"4" "EventREAD" "DataEventDuration" "TypeSec" "0.000686859" ""
>>
for just doing the first two elements in the for...end loop instead of all for brevity.
0 Comments
Luna
on 9 Jan 2019
I was assuming the same 64x9 cell. Here is my solution gives the same result with Jan's:
cellArray = cellfun(@(x) strsplit(x(:,:),' '), vertcat(data{:}), 'UniformOutput',false);
for i = 1:numel(cellArray)
for j = 1:numel(cellArray{i})
raw{i,j} = cellArray{i}{j} ;
end
end
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