MATLAB: Importing and Analyzing .txt files

data importimporting excel dataMATLAB

How can I import multiple files into matlab and then for example only get data from certain columns and certain parts of that column? For example I could have a .txt file with 1,000 lines and 3 columns (date, flowrate1,flowrate2). The dates range from jan-dec and I only want to import data from columns 2,3 (flowrate1,flowrate2) from the month of March?

Best Answer

https://www.mathworks.com/help/matlab/ref/timerange.html

You can use readtable() and convert to timetable() objects, and use timerange() indexing.

Alternately, you can use readtable(), and use month() on the date column, and compare the result to 3 in order to get a mask for which rows to use. Note that this would find all March items from separate years if there are multiple years in the file.

Related Solutions

MATLAB: How to pick the right month

Price = Data1(:,1);
Demand = Data1(:,2);
tv = (datetime([2003,1,1]):datetime([2015,12,31])).';
[Y,M,D] = ymd(tv);
DT = timetable(Price, Demand, Y, M, D, 'RowTimes', tv);

Now you can do tests such as

MarchData = DT(DT.M==3,:);

and you can also use timerange() selectors, https://www.mathworks.com/help/matlab/ref/timerange.html

and you can also do calculations such as

retime(DT, 'monthly', 'sum')

MATLAB: Export CSV file with timestamp in filename

I’m not certain exactly what you want, but this will get you started:

filename = sprintf('CSV File %s.csv', datestr(now));

produces:

filename =
CSV File 02-Feb-2015 10:16:58.csv

You can specify the format of the timestamp with the ‘formatOut’ parameter of datestr, for example:

filename = sprintf('CSV File %s.csv', datestr(now, 'dd.mm.yyyy HH:MM'))

produces:

filename =
CSV File 02.02.2015 10:20.csv

Best Answer

Related Solutions

MATLAB: How to pick the right month

MATLAB: Export CSV file with timestamp in filename

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