Why i am getting Nan?

I'm trying to download the weather forecast from a site.

close all
clear all


%%download weather forecast data from server
 current_files=urlread('https://www.sinoptik.bg/sofia-bulgaria-100727011?location');
 relev_files=strfind(current_files,'FPTO51.0_r1101_TA.csv');
 %for most recent file use last index in relev_files 
 ta_url=['https://www.sinoptik.bg/sofia-bulgaria-100727011?location',current_files(relev_files(1:end)-21:relev_files(1:end)+20)];
 % ta_url=['http://dd.weatheroffice.ec.gc.ca/meteocode/ont/csv/',current_files(relev_files(1:end)-21:relev_files(1:end)+20)];
 ta_data=urlread(ta_url);
 
 %%put forecast data into vectors
 clc
 C = [strsplit(ta_data, '\n')]' ;
 D = char(C(2:end-1));
 for I = 1:numel(D,1)
    E = strsplit(D(I,:));
    year(I)=str2double(char(E(1,1)));
    month(I) = str2double(char(E(1,2)));
    F =char( E(1,3));
    G = strsplit(F, 'T');
    day(I) = str2double(char(G(1,1)));
    H = char(G(1,1));
    J = strsplit(H, ':');
    hour(I) = str2double(char(J(1,1)));
    min(I) = str2double(char(J(1,2)));
    K = J{1,1};
    L = strsplit(K, 'Z');
    sec(I) = str2double(char(L(1,1)));
    M = L{1,1};
    N = strsplit(M, ',');
    value(I) = str2double(char(N(1,1)));
 end
 
 

 %F = strsplit(D(1,:), 'T')
 data=[year' month' day' hour' min' sec' value'];
 figure
 t = datetime(year, month, day, hour, min, sec);
 plot(t, value, '*')
 hold on
 plot(t, value, '-k', 'Linewidth', 2)
 axis tight, grid minor
 xlabel('Time')
 ylabel('Temperature (°C)')

[Adam]

Getting NaN where? You create about 24 variables in that code.

Answer 1

[Cam Salzberger]

Any time str2double is unable to translate a particular input into a number, it returns NaN. That is probably where the issue is occuring, so consider checking the inputs more carefully. Also, numel generally takes just one input. I think you meant to use size(D, 1).

-Cam

Answer 2

[Walter Roberson]

There is no year in any line until after line 1800.