MATLAB: Importing csv file into MATLAB gives an error

%f%scsvdatadelimitererrorexcelformatMATLABreadtabletable

I am trying to read in a CSV-file into MATLAB R2013b, but I keep receiving errors. I am positive my formatting is properly aligned with my columns in my Excel sheet.

>> exampletable = readtable('example.csv', 'ReadVariableNames',false, 'Delimiter',',', 'TreatAsEmpty','', 'Format','%s%s%s%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f');

Error using table/readTextFile (line 184)

Unable to read the entire file. You may need to specify a different format string, delimiter, or

number of header lines.

Error in table.readFromFile (line 41)

t = table.readTextFile(filename,otherArgs);

Error in readtable (line 114)

t = table.readFromFile(filename,varargin);

Caused by:

Reading failed at line 1. A field on that line may have contained the wrong type of value.

Best Answer

In R2013b, you must specify the 'FileType' as 'spreadsheet'. You do not need to give MATLAB the format for every column nor give a 'Delimiter' because it is a spreadsheet.

>> exampletable = readtable('example.csv','FileType', 'spreadsheet', 'ReadVariableNames', false);

In newer versions of MATLAB, such as R2016a and later, you can simply call:

>> exampletable = readtable('example.csv');

Related Solutions

MATLAB: Error with “timetable” when using the same “VariableNames” argument as for successful use of “table”

This issue has to do with the different way "timetable" treats the column that represents the time. When you specify "VariableNames" for "timetable", it refers only to the columns other than the time column.

So to achieve the desired outcome in the example, you can execute the following command

>> tt2 = timetable(dates, info, 'VariableNames', {'Info'});

If you would like to change the name of the time column as well (from the default "Time" to "Date"), this can be done with the "DimensionNames" property:

>> tt2.Properties.DimensionNames = {'Date', 'Variables'};

This information can be found in the documentation:

<https://www.mathworks.com/help/matlab/matlab_prog/create-timetables.html> (Create Timetable and Specify Variable Names)

<https://www.mathworks.com/help/matlab/ref/timetable.html> (Dimension names)

MATLAB: How to specify a datetime format when reading a .csv/Excel file

You can use 'setvaropts' to change the format of datetime variables. For example:

opts = detectImportOptions('example.csv');
opts = opts.setvaropts('myVariable','InputFormat','M/d/yyyy','DateTimeFormat','dd-MMM-yyyy');
t = readtable('example.csv',opts)
% 'example.csv' contains the column:
% myVariable
% 1/31/2020

'InputFormat' tells 'readtable' how to interpret the values in the file, while 'DateTimeFormat' tells MATLAB how to display the datetimes once they are in MATLAB.

For more information, refer to the "Import Date and Time Data" section on the following documentation page:

https://www.mathworks.com/help/matlab/ref/matlab.io.text.delimitedtextimportoptions.setvaropts.html

Best Answer

Related Solutions

MATLAB: Error with “timetable” when using the same “VariableNames” argument as for successful use of “table”

MATLAB: How to specify a datetime format when reading a .csv/Excel file

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