CSV file import with timestamp
4 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
I have csv data in the following format
value, timestamp, id
1.48,"2011-02-07 11:27:18+11",1
which I would like to import into Matlab so that I can look at the differences in successive time stamps. So I would like to convert the time of minutes to seconds and plot the difference. What is the best way to import this data?
0 commentaires
Réponse acceptée
Marlies
le 29 Mar 2012
To import formatted data, textscan is usually a good option.
Textscan requires you to define a format. Assuming you want to separate all the elements in the file (value, every component from the timestamp separately, id-number), your format could look like this:
fmt = %f "%u-%u-%u %u:%u:%u+%u" %u
In this format; the '%f' and '%u' represent the datatypes that MATLAB is supposed to use for the data it reads (floating point, integer). All the other signs ("-:+) are 'literals'. They tell MATLAB that it will literally find a colon (that should be ignored).
In addition, you will need to define in the textscan-command that the delimiter is a comma
textscan(fid,fmt,'delimiter',',')
Hope this helps
Marlies
0 commentaires
Plus de réponses (1)
Kye Taylor
le 29 Mar 2012
The assignment
fmt = %f "%u-%u-%u %u:%u:%u+%u" %u
should be
fmt = '%f "%u-%u-%u %u:%u:%u+%u" %u'
(notice the single quotes). To make the unpacking of output from textscan slightly easier, you could define fmt as below. Note the fopen and fclose statements before and after invoking textscan.
fmt = '%f%q%f';
fid = fopen('yourFileName.csv');
nowInMatlab = textscan(fid,fmt,'delimiter',',');
fclose(fid);
0 commentaires
Voir également
Catégories
En savoir plus sur Data Import and Export dans Help Center et File Exchange
Produits
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!