Skipping the column header from textread

Question

Matt Rulli 2018-4-15

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https://ww2.mathworks.cn/matlabcentral/answers/394967-skipping-the-column-header-from-textread

回答： Gabriel Felix 2020-5-24

I'm importing data from a text file with a list of names, but I need to skip the column header that says "FirstName".

list = textread(names.text,'%s %*s')' % skips second column and translates from column vector to row vector

How do I tell MATLAB to skip the header? In other words, I need textread to skip the first row in the list.

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Answer 1

Walter Roberson 2018-4-15

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https://ww2.mathworks.cn/matlabcentral/answers/394967-skipping-the-column-header-from-textread#answer_315166

'headerlines', 1

Note: textread() is not recommended. It has been considered obsolete for years.

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Walter Roberson 2018-4-15

在 MATLAB Online 中打开

fid = fopen(filename, 'rt');
listcell = textscan(fid, '%s %*s', 'headerlines', 1);
fclose(fid);
list = listcell{1};

However I would suggest

fid = fopen(filename, 'rt');
listcell = textscan(fid, '%s%*[^\n]', 'headerlines', 1);
fclose(fid);
list = listcell{1};

This would read to end of line and skip that. The %*s you used would only skip to the end of the first non-whitespace.

Matt Rulli 2018-4-15

Walter.... You are an angel walking amongst mere mortals! Thank you, sir!!

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Answer 2

Gabriel Felix 2020-5-24

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此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/394967-skipping-the-column-header-from-textread#answer_437758

在 MATLAB Online 中打开

I had to use \n at the end of each line. Without it I couldn't make textscan() work properly, even thoug the "HeaderLines" was configured according to the text file lines. This was the only solution I found after struggling with the code for an intire day.

This was the text:

!
!
! alfa (graus) =  5.0
!
! Id.      x/s       z/s     alfai       cl     c*cl/cmed    cdi      cmc/4
!                           (graus)
   1      .246      .050    -1.209      .255      .332     .00538     .0170
   2      .292      .150    -1.098      .259      .319     .00496     .0545
   3      .339      .250     -.925      .254      .297     .00410     .0944
   4      .385      .350     -.741      .243      .268     .00315     .1341
   5      .432      .450     -.561      .227      .235     .00223     .1714
   6      .479      .550     -.393      .206      .199     .00141     .2034
   7      .525      .650     -.238      .181      .163     .00075     .2266
   8      .572      .750     -.101      .152      .126     .00027     .2362
   9      .619      .850      .014      .116      .089    -.00003     .2236
  10      .659      .938      .103      .074      .052    -.00013     .1693
!
! CL asa    =  .208
! CDi asa   =  .00258
! e (%)     =  88.9
! CMc/4 asa =  .1339

My code:

%! alfa (graus) =  5.0
P = textscan(fid,'! alfa (graus) = %f','Delimiter',' ','MultipleDelimsAsOne',true,'headerLines',2,'CollectOutput',1);
alpha(1) = P{1};
%! CL asa    =  .208
P = textscan(fid,'! CL asa = %f\n','Delimiter',' ','MultipleDelimsAsOne',true,'CollectOutput',1,'headerLines',4+n);
CL(1) = P{1};
%! CDi asa   =  .00258
P = textscan(fid,'! CDi asa   =  %f\n','Delimiter',' ','MultipleDelimsAsOne',true,'CollectOutput',1,'headerlines',0);
CDi(1) = P{1};
%! CMc/4 asa =  .1339
P = textscan(fid,'! CMc/4 asa = %f','Delimiter',' ','MultipleDelimsAsOne',true,'CollectOutput',1,'HeaderLines',2);
Cmc4(1) = P{1};