Include Newline in Textscan
15 views (last 30 days)
Show older comments
I have the following function for auto-importing data from a tabular text file with delimiter " ".
function RMM_New_Bins = Import_RMM(filename, startRow, endRow)
delimiter = ' ';
if nargin<=2
startRow = 1;
endRow = inf;
end
formatSpec = '%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%[^\n\r]';
fileID = fopen(filename,'r');
textscan(fileID, '%[^\n\r]', startRow(1)-1, 'WhiteSpace', '', 'ReturnOnError', false);
dataArray = textscan(fileID, formatSpec, endRow(1)-startRow(1)+1, 'Delimiter', delimiter, 'ReturnOnError', false);
for block=2:length(startRow)
frewind(fileID);
textscan(fileID, '%[^\n\r]', startRow(block)-1, 'WhiteSpace', '', 'ReturnOnError', false);
dataArrayBlock = textscan(fileID, formatSpec, endRow(block)-startRow(block)+1, 'Delimiter', delimiter, 'ReturnOnError', false);
for col=1:length(dataArray)
dataArray{col} = [dataArray{col};dataArrayBlock{col}];
end
end
fclose(fileID);
RMM_New_Bins = [dataArray{1:end-1}];
How do I include blank lines that are tabs in the RMM_New_Bins? I think it has to do with the textscan command.
5 Comments
Stephen23
on 20 Jul 2016
@Suganth Kannan: please edit your question and upload a sample file by clicking the paperclip button.
Answers (1)
dpb
on 20 Jul 2016
Edited: dpb
on 23 Jul 2016
Pretty bizzaro request: "Line 2 (blank) should not show up in the imported array. Only lines 1, 3, 4 (blank), 5, and 6 (blank) should show up" but whatever...
As it's a mixture of data can only have it as a (padded) character array or a cellstr array--I'll choose cellstr as it's much more flexible--
>> f=textread('sample.txt','%s','delimiter','\n','whitespace',''); % read full file as cellstr
>> f(cellfun(@isempty,f))=[]; % eliminate any totally blank rows
>> f % display result...
f =
' 4[A] 6[B] 7[C] '
'4[A] 0 6.23022 '
' '
'6[B] 6.23022 0 '
' '
>>
"How do I include blank lines that are tabs..."
ADDENDUM 2: Lines which contain tabs aren't really blank. Of course, to read them you have to use a way that doesn't treat them as delimiters or whitespace which the above does in reading each record as a cell string.
Then, as modified above, you can simply test for and eliminate those records that were, indeed, blank (and, hence, return TRUE for isempty on the record. Note that isempty on the array f is not the same thing as applying isempty to each member of the cell array which cellfun does).
Continuing after the diversion the previous illustration--
>> ~cellfun(@isempty,strfind(f,char(9)))
ans =
0
0
1
0
1
>> find(~cellfun(@isempty,strfind(f,char(9))))
ans =
3
5
>>
ADDENDUM
You can, of course, read the non-blank fields in the file with textscan, but it is impossible other than by parsing character-by-character to separate a blank field from a blank delimiter and so all you'll be able to get with it will be the non-missing data--
>> fid=fopen('sample.txt','r');
>> f=textscan(fid,repmat('%s',1,3),'collectoutput',1)
f =
{3x3 cell}
>> f{:}
ans =
'4[A]' '6[B]' '7[C]'
'4[A]' '0' '6.23022'
'6[B]' '6.23022' '0'
>>
3 Comments
dpb
on 22 Jul 2016
Edited: dpb
on 23 Jul 2016
I have no idea what "If you could edit based of this info, ..." means; I gave you a way to import the data and find rows containing a tab; if the idea is to eliminate rows that are all blank and delete them but keep those with the tab, then
f(cellfun(@length,f)==0)=[];
instead of the aforementioned fixed 2 after reading the file should clean those lines out.
dpb
on 23 Jul 2016
It dawned on me overnight it's actually an empty string if length()==0 so use the simpler test instead. I made a second update to the original answer incorporating same...
See Also
Categories
Find more on Text Files in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!