I am working with tmy3 files, and I have csv hourly data for a whole year. I need to get the maximum of a certain value for each month and plot them and also performing addition to another value for each day and getting the max and min day?

I am working with tmy3 (csv) (8762*68) files, and I have hourly data for a whole year.

I need to get the maximum of a certain column for each month and plot them together (12 points) and also to perform addition to another column for each day and getting the max and min day for this addition.

I have been struggling with both issues for a while as I am not so good with Matlab, any help would be appreciated. If this is easier in Python I am open to help in it as well.

Attached the full tmy3 (8762*68) file that you can see to start helping me.

[Rik]

What have you tried so far? Have a read here (or here for more general advice). It will greatly improve your chances of getting an answer.

Answer 1

[darova]

I've imported 8th column (3:end rows) to MATLAB and found max value of each month

plot(DNIWm2)

days = [0 31 28 31 30 31 30 31 31 30 31 30 31];
[maxValue, maxHour] = deal(zeros(12,1));
hour = 0;
hold on
for i = 1:12;
    hour = hour + days(i)*24;
    data = DNIWm2( hour+1 : hour+days(i+1)*24 );    % extracting data of a current month
    [maxValue(i), H] = max( data );                 % local max value and hour
    maxHour(i) = H + hour;                          % hour in data
    plot([hour hour], [0 1000],'-ok')       % plot first/last hour of a month
end
plot(maxHour,maxValue,'-or')
hold off

[Omar Ibrahim]

Hey darova,

Thank you for your answer, but how did you get the max. value for each month in the 8th column?

Aslo, how can I perform a summation for each day and then get the max. and min. summation?

[Omar Ibrahim]

One more question, how to draw on a monthly basis and not an hourly one?

[darova]

If you have 31 days and 24 hour then give 31*24 rows of your data and do whatever you want.

first month: 31*24 = 744 hours (rows)

second month: 28*24 = 672 hours (rows)

third month: 31*24 = 744 hours (rows)

data of first month: 1 : 744 (rows)

data of second month: first month+1 : first month+second month = 745:744+672 = 745:1416 (rows)

maxOfday = zeros(365,1);
minOfday = zeros(365,1);

for i = 1:365
    data = DNIWm2((i-1)*24+1 : i*24);        % data of a current day
    maxOfday(i) = max(data);                 % max value
    minOfday(i) = min(data);                 % min value
end

[Omar Ibrahim]

Hey darova,

Thank you for your answer again. I can get the max and min of each day, but what I can't get is the max and min total of the DNIWm2 over a day; hence 365 summations and the max sum and min sum is to be got.

Thank you so much for your efforts, I do really appreciate it.

[darova]

Summarize values of each day then finding max and min sum

sumOfday = zeros(365,1);
for i = 1:365
    data = DNIWm2((i-1)*24+1 : i*24);        % data of a current day
    sumOfday(i) = sum(data);                 % max value
end
[smax, imax] = max(sumOfday);                
[smin, imin] = min(sumOfday);
display(['Max sum is: ',num2str(smax),'. Day: ',num2str(imax)])
display(['Min sum is: ',num2str(smin),'. Day: ',num2str(imin)])

[Omar Ibrahim]

Thank you so much! I already reached this a while ago.

Thank you for all the help, it all worked!

[Omar Ibrahim]

My very last comment or inquiry:

For the plot you conducted earlier; how can I plot in terms of months and not hours throughout the year?

[darova]

days = [0 31 28 31 30 31 30 31 31 30 31 30 31];
month_data = zeros(12,1);
for i = 1:12;
    hour = hour + days(i)*24;
    data = DNIWm2( hour+1 : hour+days(i+1)*24 );    % extracting data of a current month
    month_data(i) = sum(data);                      % or mean()
end
bar(month_data)