Importing txt files and using loops
2 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
Pouyan Msgn
le 11 Mar 2020
Réponse apportée : BobH
le 11 Mar 2020
I have three txt files and I want to use their nummerical data in Matlab
How can I ignore and neglect non-numeric texts? I want Matlab to import just numbers, there two columns of numbers in each file and I want just those numbers
I have more than one file. Here I have three files. Is it possible to use for loop to import these files and buy time?
0 commentaires
Réponse acceptée
Mario Malic
le 11 Mar 2020
Modifié(e) : Mario Malic
le 11 Mar 2020
%% Reading the file
FID_F_1 = fopen(filename , 'r');
i = 1;
tline = fgetl(FID_F_1);
A{i} = tline;
while ischar(tline)
i = i+1;
tline = fgetl(FID_F_1);
A{i} = tline;
end
fclose(FID_F_1);
Now all text is saved in variable A.
for ii = line where data starts : line where data ends
X_Temp = str2num(A{ii}); %converts the string line into array
X = X_Temp(1,1); %
Y = X_Temp(1,2); % Getting the values
end
0 commentaires
Plus de réponses (2)
Subhamoy Saha
le 11 Mar 2020
Modifié(e) : Subhamoy Saha
le 11 Mar 2020
Here I have tested with your J94.txt file
filename = 'C:\Users\Desktop\J94.txt'; %% change filepath accordingly
delimiter = ' ';
startRow = 33;
formatSpec = '%f%f%*s%*s%[^\n\r]';
fileID = fopen(filename,'r');
textscan(fileID, '%[^\n\r]', startRow-1, 'WhiteSpace', '', 'ReturnOnError', false, 'EndOfLine', '\r\n');
dataArray = textscan(fileID, formatSpec, 'Delimiter', delimiter, 'MultipleDelimsAsOne', true, 'TextType', 'string', 'EmptyValue', NaN, 'ReturnOnError', false);
fclose(fileID);
Col1 = dataArray{:, 1};
Col2 = dataArray{:, 2};
clearvars filename delimiter startRow formatSpec fileID dataArray ans;
You can use multiple files using loop if those file names are in some order. Otherwise use uigetfile().
0 commentaires
BobH
le 11 Mar 2020
Similar to Mario Malic but using regular expressions
R = []; % init to empty
fid = fopen('J94.txt','r');
t = fgetl(fid);
while( ischar(t) )
reNum = '([0-9.E\+]+)';
m = regexp(t, ['^\s*' reNum '\s+' reNum], 'tokens','once');
if( length(m) == 2 ) % found two matches in the line
R(end+1,:) = cellfun(@str2num, m);
end
t = fgetl(fid);
end
fclose('all');
0 commentaires
Voir également
Catégories
En savoir plus sur Large Files and Big Data dans Help Center et File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!