converting multiple textfiles to csv and xlsx format.

Question

Arnab Paul 2022-9-17

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1807180-converting-multiple-textfiles-to-csv-and-xlsx-format

评论： Arnab Paul 2022-9-19

采纳的回答： Walter Roberson

f64d5aab60_IOP_20130909_2155.txt

在 MATLAB Online 中打开

I have the code for the one file. how can I loop it through?

Here is the code.

filename = 'myFile.txt';
format = '%c';
data=readlines(filename);
data = replace(data, ",", " ");
% data=strrep(data,char(9),',');
%mat = char(data1);
%int = str2double(data1);
writelines(data, 'myFile.csv');
opts = delimitedTextImportOptions("NumVariables", 522);
% Specify range and delimiter
otps.row = [3, 33];
otps.Delimiter = " ";
% Specify column names and types
opts.VNames = ["bin_depth", "depth", "wt", "salinity", "stimf"]
otps.VTypes = ["double", "double", "double", "double", "double"]
table = readtable( "myFile.csv", opts);
writetable(table, 'myFile.xlsx', 'sheet',1,'Range','A1')

I also want to retain the respective names of the text files.

2 个评论
显示无隐藏无

Walter Roberson 2022-9-17

Why would you bother reading the file, changing the delimiter to space, writing the file, reading the file, writing the file?

Why not just readtable() specifying the VariableNames and writetable that? If you need to skip lines you can do that when reading from the original file.

You create options for 522 columns but you only set variable names for 4, which will be a problem.

Arnab Paul 2022-9-17

Well I have attached a sample file. I am reading it because I wanted to see how it looks like, and I wanted both csv and excel data. also, well a newbie approach. It has mixed delimters and 522 variables/columns but I did not want to put all of them together. That's why.

Thank you.

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Walter Roberson 2022-9-17

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1807180-converting-multiple-textfiles-to-csv-and-xlsx-format#answer_1055575

编辑：Walter Roberson 2022-9-17

在 MATLAB Online 中打开

format long g
filename = 'https://www.mathworks.com/matlabcentral/answers/uploaded_files/1128290/f64d5aab60_IOP_20130909_2155.txt';
Lines = readlines(filename);
%variable names are on the first line
variablenames = regexp(Lines(1), ',', 'split');
variablenames(1:5) = ["bin_depth", "depth", "wt", "salinity", "stimf"];
%get rid of lines that do not start with a number
Lines( cellfun(@isempty, regexp(Lines, '^\d')) ) = [];
%we are going to use textscan(), which needs the text as a continuous
%string, not an array
as_text = strjoin(Lines, newline);
%textscan can figure out how many columns there are if you use empty format
%textscan returns cell array; we convert that to array and array to table
fmt = '';
data = array2table( cell2mat( textscan(as_text, fmt)), 'VariableNames', variablenames);
writetable(data, 'myFile.xlsx', 'sheet',1,'Range','A1')

3 个评论
显示 1更早的评论隐藏 1更早的评论

Walter Roberson 2022-9-19

在 MATLAB Online 中打开

dinfo = dir('*IOP*.txt');
filenames = fullfile({dinfo.folder}, {dinfo.name});
num_files = length(filenames);
for K = 1 : num_files
    filename = filenames{K};
    
    Lines = readlines(filename);
    and so on
end

But be careful -- you are not going to be overwriting the same column of the same sheet of the same file. Perhaps use 'sheet', K instead of 'sheet', 1

Arnab Paul 2022-9-19

在 MATLAB Online 中打开

myFolder = '/Users/gulfcarbon2/Downloads/Modis/absorption file';
filePattern = fullfile(myFolder, '*.txt'); % Files with .txt extension
theFiles = dir(filePattern);
for k = 1:length(theFiles)
    baseFileName = theFiles(k).name;
    fullFileName = fullfile(theFiles(k).folder, baseFileName);
    fprintf(1, 'Now reading %s\n', fullFileName);
    Lines = readlines(fullFileName);
    %variable names are on the first line
    variablenames = regexp(Lines(1), ',', 'split');
    variablenames(1:5) = ["bin_depth", "depth", "wt", "salinity", "stimf"]
    %get rid of lines that do not start with a number
    Lines( cellfun(@isempty, regexp(Lines, '^\d')) ) = [];
    %we are going to use textscan(), which needs the text as a continuous
    %string, not an array
    as_text = strjoin(Lines, newline);
    %textscan can figure out how many columns there are if you use empty format
    %textscan returns cell array; we convert that to array and array to table
    fmt = '';
    data = array2table( cell2mat( textscan(as_text, fmt)), 'VariableNames', variablenames);
    writetable(data, [baseFileName, '.xlsx'], 'sheet',1,'Range','A1')
end