Why doesn't 'HeaderLines' work in the readtable command?

Question

njj1 2018-3-31

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评论： Jeremy Hughes 2022-7-7

I am importing some excel files into Matlab using the readtable command. There are a couple of header lines in the file that I would like to skip, but when I use the name-value pair ('HeaderLines',2), I get an error:

Error using readtable (line 198)
Invalid parameter name: HeaderLines.

Has anyone else experienced this? Is there a way to get around this error?

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Answer 1

Walter Roberson 2018-3-31

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https://www.mathworks.com/help/matlab/ref/readtable.html#namevaluepairarguments

"When reading:

Text files, only these parameter names apply: FileType, ReadVariableNames, ReadRowNames, TreatAsEmpty, DatetimeType, Delimiter, HeaderLines, Format, EmptyValue, MultipleDelimsAsOne, CollectOutput, CommentStyle, ExpChars, EndOfLine, DateLocale, and Encoding.
Spreadsheet files, only these parameter names apply: FileType, ReadVariableNames, ReadRowNames, TreatAsEmpty, DatetimeType, Sheet, Range, Basic, and TextType.
Text or Spreadsheet files with the opts import options, only these parameter names apply: ReadVariableNames, ReadRowNames, DateLocale, Encoding, Sheet, and Basic. "

You are reading a spreadsheet file. You need to use Range instead of HeaderLines

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Jeremy Hughes 2022-7-7

For more recent releases, NumHeaderLines is allowed in spreadsheet files.

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Answer 2

Bradley Stiritz 2018-10-21

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编辑：Bradley Stiritz 2019-4-25

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Walter's solution is a good one, when the number of table rows are known in advance. In my case, I have Excel files with a fixed number of header rows, and variable number of data rows.

I reached out to tech support, and got the following solution. This works well for me, I hope it can help others also--

% Assume Excel file has 6 header rows
>>path_ = 'C:\data\my_file.xlsx';
>>ImportOptions_ = detectImportOptions(path_, 'NumHeaderLines', 6);
>>tb = readtable(path_,ImportOptions_);

(Edit: corrected minor bugs per Doug Bergman)

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Doug Bergman 2019-4-25

编辑：Doug Bergman 2019-4-25

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Brad, your solution worked well for me, once i realized that

path

is the full filename and not just the directory path, and

IOpts

is the same as

ImportOptions_

Thanks for posting, saved me a day of pulling my hair out.

Bradley Stiritz 2019-4-25

Hi Doug, thank you for your comment and correction notes. I'm glad you were able to save some time. Apologies for the sloppy code example, I have edited my post accordingly.

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