octave_importglobal.m

% Function to import time series CSV files for COVID data. Written for the 
% following specific files:
%   - 'time_series_covid19_confirmed_global.csv'
%   - 'time_series_covid19_deaths_global.csv'
% from:
% 'https://github.com/CSSEGISandData/COVID-19/raw/master/csse_covid_19_data/csse_covid_19_time_series/'
%__________________________________________________________________________
# Copyright (C) 2021 Embecosm Limited
# Contributor: William Jones <william.jones@embecosm.com>
# SPDX-License-Identifier: GPL-2.0
function out = octave_importglobal(filename, delim)
  if (nargin < 2)
    delim = ',';
  end
  lines = textread(filename, '%s', "delimiter", "\n");
  data = [];
  textdata = {};
  for i = 1:length(lines)
    line = lines{i,1};
    data_counter = 1;
    text_counter = 1;
    quote_open = 0;
    buffer = '';
    for j = 1:(length(line)+1)
      if(j <= length(line))
        current_char = line(j);
      else
        current_char = delim;
      end
      if(current_char == ("\""))
        quote_open = !quote_open;
        continue;
      end
      if((current_char == delim)&&!quote_open)
        if (i == 1)
          textdata{i, text_counter} = buffer;
          text_counter = text_counter + 1;
        else
          if text_counter < 3
            textdata{i, text_counter} = buffer;
            text_counter = text_counter + 1;
          else
            if(isempty(buffer))
              data(i-1, data_counter) = NaN;
            else
              try
                data(i-1, data_counter) = str2num(buffer);
              catch
                disp(buffer);
              end
            end
            data_counter = data_counter + 1;
          end
        end
        buffer = '';
      else
        buffer = [buffer, current_char];
      end
    end
  end
  out.data = data;
  out.textdata = textdata;
end