read csv data with numbers, characters and text

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Simon Lind 2023-5-22

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评论： Cris LaPierre 2023-5-23

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sample.csv

Greetings

Does anyone have any idea on how to import numerical data from a csv file of the following format:

STATION DATE LATITUDE LONGITUDE ELEVATION NAME PRCP PRCP_ATTRIBUTES TMAX TMAX_ATTRIBUTES TMIN TMIN_ATTRIBUTES

BC000068026 01/02/32 -18.367 21.85 1000 SHAKAWE, BC 0 ,,Q

I'm attaching a sample file

Matlab2016b

Thank you very much in advance

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Simon Lind 2023-5-22

detectImportOptions is a very good tip

Image Analyst 2023-5-22

If the format is too custom and varies from file to file, you may have to write your own custom reader where you read a line at a time and parse it appropriately.

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Cris LaPierre 2023-5-23

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编辑：Cris LaPierre 2023-5-23

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Have you tried readtable? What didn't work about it? I get the results I would expect. It even successfully ignored the delimiters inside quotes.

The file has 12 delimited fields, the names of which are given in the first line of your file.

The "SHAKAWE, BC" AND ",,Q" are each considered single variables (NAME and PRCP ATTRIBUTES). When I use readtable in R2016b with no options, I get this:

Notice the warning about dates. I suspect it should be dd/MM/yy. Use the options to fix that.

opts = detectImportOptions('sample.csv');
opts = setvaropts(opts,'DATE','InputFormat','dd/MM/yy');
data = readtable('sample.csv',opts)

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Simon Lind 2023-5-23

移动：Cris LaPierre 2023-5-23

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I followed your advices. This was what I finally did and it works

Thank you very much

opts.SelectedVariableNames = {'DATE','LATITUDE','LONGITUDE','PRCP'};
T = readtable([datapath myfile],opts);
t = table2array(T(:,1));
lat = table2array(T(:,2));
lon = table2array(T(:,3));
p = table2array(T(:,4));
lon = str2num(cell2mat(lon));
lat = str2num(cell2mat(lat));
t = datenum(t);
p = str2num(cell2mat(p));