Getting NaN when converting string to number
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Hi, I am reading the first line of 4 text files and trying to convert the second column in each file name to a number as i have time stored in the second column. When i convert the second row of elements to number, i am getting NaN. Screen shot of first line of a text file is attached. Any help to solve this will be appreciated.
first_row_of_text_file = cell(number_of_files,1);
for ii = 1:number_of_files
fileID = fopen(filenames{ii},'r');
varNames = textscan(fileID, format, 1, 'Delimiter', delimiter, 'MultipleDelimsAsOne', true, 'TextType', 'string', 'ReturnOnError', false);
first_row_of_text_file{ii} = str2double(varNames(:,2));
end
8 个评论
Stephen23
2018-8-21
@Hari Krishnan: please upload a sample file by clicking the paperclip button.
Hari krishnan
2018-8-21
jonas
2018-8-21
How do you want to convert 13:00:02.754000 to a number? What is your desired output?
Hari krishnan
2018-8-21
How do you write 13:00:02.754000 in numeric form? I mean, let's say:
A=13:00:02.754000
out=A/2
What is the expected answer?
You may want to look into converting it to a datetime or datenum (double)
Finally, in your previous questions (see e.g. this one ), you already converted the entire textfile to a MATLAB table. Why are you even still working with this text file?
Walter Roberson
2018-8-21
Or into a duration.
Hari krishnan
2018-8-21
Then you can convert the string to either a duration or datetime. After subtraction, the format will be duration regardless. In this case I'd suggest going for duration directly as you don't have any date in the same cell.
I still don't understand why you don't use the timetable that I helped you build some days ago. It would be extremely easy to calculate the time difference.
回答（1 个）
Kuifeng Zhao
2018-8-21
0 个投票
I suggest change the brackets (),[], into comma ',', and then try to read the data again. Anyway, you can try the function and make necessary changes: importdata('data.txt').
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2018-8-21
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