how to delete permanently the first row of this table

조회 수: 5(최근 30일)
MA
MA 2021년 9월 15일
댓글: MA 2021년 9월 16일
Hi, This table was baiscally a data file that I have imported using 'import data tool', I woud like to get rid of the first row in this tabel contaning tthe non values but I am not sure how to do that, because every time I try to delete it when I run the code again it returs back.. so what can I do?
  댓글 수: 2
MA
MA 2021년 9월 15일
Thank you for replying to my question. I am basically using the script generated by matlab and here it is and the data file is attached (just aside note I am only using a specific columns from the data file not all of them)
%% Import data from text file.
% Script for importing data from the following text file:
%
% C:\Users\Windows 10 Pro\Documents\MATLAB\jro19661111.001.txt
%
% To extend the code to different selected data or a different text file, generate a function instead of a script.
% Auto-generated by MATLAB on 2021/09/15 17:22:30
%% Initialize variables.
filename = 'C:\Users\Windows 10 Pro\Documents\MATLAB\jro19661111.001.txt';
%% Read columns of data as text:
% For more information, see the TEXTSCAN documentation.
formatSpec = '%6s%10s%10s%10s%10s%*10*s%*13*s%*11*s%*14*s%*14*s%*14s%11s%14s%[^\n\r]';
%% Open the text file.
fileID = fopen(filename,'r');
%% Read columns of data according to the format.
% This call is based on the structure of the file used to generate this code. If an error occurs for a different file, try regenerating the code from the Import Tool.
dataArray = textscan(fileID, formatSpec, 'Delimiter', '', 'WhiteSpace', '', 'TextType', 'string', 'ReturnOnError', false);
%% Close the text file.
fclose(fileID);
%% Convert the contents of columns containing numeric text to numbers.
% Replace non-numeric text with NaN.
raw = repmat({''},length(dataArray{1}),length(dataArray)-1);
for col=1:length(dataArray)-1
raw(1:length(dataArray{col}),col) = mat2cell(dataArray{col}, ones(length(dataArray{col}), 1));
end
numericData = NaN(size(dataArray{1},1),size(dataArray,2));
for col=[1,2,3,4,5,6,7]
% Converts text in the input cell array to numbers. Replaced non-numeric text with NaN.
rawData = dataArray{col};
for row=1:size(rawData, 1)
% Create a regular expression to detect and remove non-numeric prefixes and suffixes.
regexstr = '(?<prefix>.*?)(?<numbers>([-]*(\d+[\,]*)+[\.]{0,1}\d*[eEdD]{0,1}[-+]*\d*[i]{0,1})|([-]*(\d+[\,]*)*[\.]{1,1}\d+[eEdD]{0,1}[-+]*\d*[i]{0,1}))(?<suffix>.*)';
try
result = regexp(rawData(row), regexstr, 'names');
numbers = result.numbers;
% Detected commas in non-thousand locations.
invalidThousandsSeparator = false;
if numbers.contains(',')
thousandsRegExp = '^[-/+]*\d+?(\,\d{3})*\.{0,1}\d*$';
if isempty(regexp(numbers, thousandsRegExp, 'once'))
numbers = NaN;
invalidThousandsSeparator = true;
end
end
% Convert numeric text to numbers.
if ~invalidThousandsSeparator
numbers = textscan(char(strrep(numbers, ',', '')), '%f');
numericData(row, col) = numbers{1};
raw{row, col} = numbers{1};
end
catch
raw{row, col} = rawData{row};
end
end
end
%% Replace non-numeric cells with NaN
R = cellfun(@(x) ~isnumeric(x) && ~islogical(x),raw); % Find non-numeric cells
raw(R) = {NaN}; % Replace non-numeric cells
%% Create output variable
jro19661111 = table;
jro19661111.YEAR = cell2mat(raw(:, 1));
jro19661111.MONTH = cell2mat(raw(:, 2));
jro19661111.DAY = cell2mat(raw(:, 3));
jro19661111.HOUR = cell2mat(raw(:, 4));
jro19661111.MIN = cell2mat(raw(:, 5));
jro19661111.GDALT = cell2mat(raw(:, 6));
jro19661111.NE8 = cell2mat(raw(:, 7));
%% Clear temporary variables
clearvars filename formatSpec fileID dataArray ans raw col numericData rawData row regexstr result numbers invalidThousandsSeparator thousandsRegExp R;

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채택된 답변

Image Analyst
Image Analyst 2021년 9월 15일
% Read table from txt file:
t = readtable('jro19661111.001.txt')
% Delete first row
t(1,:) = [];
  댓글 수: 2
MA
MA 2021년 9월 16일
thank you.

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