To plot one stem with multiple values for data of different months.

Question

Amjad Iqbal 2024-5-22

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2121481-to-plot-one-stem-with-multiple-values-for-data-of-different-months

评论： Mathieu NOE 2024-5-22

采纳的回答： Voss

Processed_results.zip

Dear MATLAB Experts,

I have data in .mat files, each corresponding to a particular month with selected_dates and brightness information.

Each month has a different number of output values (1, 2, 3, ..., N). I need to create a stem plot for each month, with the month on the x-axis and brightness on the y-axis.

For example, if D201701 has six values, the plot will show six values in one single stem, and the x-axis will display the month name.

Additionally, I want to annotate each stem value with a marker (e.g., . or *) to indicate the corresponding date. I have attached an image that shows the stem plot for multiple values, as well as the data and code.

Thank you for guidance and help.

2 个评论
显示无隐藏无

Cris LaPierre 2024-5-22

Are you trying to duplicate the image you shared? If so, I don't see how this is a stem plot, since stem plots would all originate from a common horizontal line. It looks like a bunch of line plots to me.

Amjad Iqbal 2024-5-22

编辑：Amjad Iqbal 2024-5-22

@Cris LaPierre

Yes, I actually wanted to emphasis that I want to plot one stem line for one month to show all the values corresponding to brightness. I understand from image its confusing.

@Voss understood the query and resolved. I appreicate both for time and efforts.

I will further norish the results.

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Voss 2024-5-22

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2121481-to-plot-one-stem-with-multiple-values-for-data-of-different-months#answer_1461806

在 MATLAB Online 中打开

Processed_results.zip

Maybe something along these lines:

unzip('Processed_results.zip')

% load the files

F = dir(fullfile('Processed_results','*.mat'));

NF = numel(F);

for ii = 1:NF

S = load(fullfile(F(ii).folder,F(ii).name));

F(ii).brightness = S.all_brightness_values;

F(ii).dates = S.selected_dates;

end

% count the number of dates and brightnesses in each file

N_dates = arrayfun(@(x)numel(x.dates),F);

N_brightness = arrayfun(@(x)numel(x.brightness),F);

assert(isequal(N_dates,N_brightness))

% collect date and brightness values into matrices;

% each column is a file, each row is a brightness/date

NB = max(N_brightness);

dates = NaT(NB,NF);

brightness = NaN(NB,NF);

for ii = 1:NF

dates(1:N_dates(ii),ii) = F(ii).dates;

brightness(1:N_brightness(ii),ii) = F(ii).brightness;

end

% construct datetime dt representing the start of each month

dt = datetime(year(dates(1,:)),month(dates(1,:)),1);

% markers to be used in plots

markers = '.*xo+^v<>sdph';

markers = repmat(markers,1,ceil(NB/numel(markers)));

% plot stems

figure('Position',[50 50 1500 600])

hold on

for ii = 1:NB

stem(dt,brightness(ii,:),'Marker',markers(ii),'MarkerSize',12)

end

xticks(min(dt):calmonths(1):max(dt))

% or plot markers only

figure('Position',[50 50 1500 600])

hold on

for ii = 1:NB

plot(dt,brightness(ii,:),'LineStyle','none','Marker',markers(ii),'MarkerSize',12)

end

xticks(min(dt):calmonths(1):max(dt))

2 个评论
显示无隐藏无

Amjad Iqbal 2024-5-22

@Voss I really appreciate your kind efforts and providing the solution.

This is what I wanted to plot and show the results. Once again Thank you.

Voss 2024-5-22

You're welcome!

请先登录，再进行评论。

Answer 2

Mathieu NOE 2024-5-22

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2121481-to-plot-one-stem-with-multiple-values-for-data-of-different-months#answer_1461856

在 MATLAB Online 中打开

hello @Amjad Iqbal

I modified a bit your code

added one line in the first for loop

    number_of_data_thismonth(k) = numel(brightnessValues);  % <= added this line first

then modified the plot

    % original plot
    % for i = 1:numel(allDates)
    %     % Plotting the stem for each date
    %     stem(allDates(i), allBrightnessValues(i), 'filled');
    %     % Extracting time information
    %     time_info = datestr(allDates(i), 'HH:MM:SS');
    %     % Adding time information on top of each stem
    %     text(allDates(i), allBrightnessValues(i), time_info, 'VerticalAlignment', 'bottom', 'HorizontalAlignment', 'center');
    % end
    
    % modified plot
    nnn = 1+[0 cumsum(number_of_data_thismonth)]; % cumulative sum of nb of data per month
    for i = 1:numel(number_of_data_thismonth)
        ind_start = nnn(i);
        ind_stop = nnn(i+1) - 1;
        ll(i) =  ind_stop - ind_start +1; % ll is equal to number_of_data_thismonth, so we have a working code 
        % Plotting the stem for each date
        % x position is "center" data 
        ind = round(mean(ind_start:ind_stop));
        stem(repmat(allDates(ind),ll(i),1), allBrightnessValues(ind_start:ind_stop), 'filled');
        % Extracting time information
        time_info = datestr(allDates(ind_start:ind_stop), 'HH:MM:SS');
        % Adding time information on top of each stem
        text(repmat(allDates(ind),ll(i),1), allBrightnessValues(ind_start:ind_stop), time_info, 'VerticalAlignment', 'bottom', 'HorizontalAlignment', 'center');
    end

your original plot looks like

now the modified plot is :

try it ; hope it helps - full code below

clear;clc;close;
% List all .mat files in the directory
matFiles = dir('*.mat');
% Initialize cell arrays to hold aggregated data
allBrightnessValues = [];
allDates = [];
% Loop through each .mat file
for k = 1:length(matFiles)
    % Load the current .mat file
    data = load(matFiles(k).name);
    
    % Extract the data
    brightnessValues = data.all_brightness_values;
    dates = data.selected_dates;
    
    % Ensure data consistency
    if isrow(brightnessValues)
        brightnessValues = brightnessValues';
    end
    
    number_of_data_thismonth(k) = numel(brightnessValues);  % <= added this line first
    
    % Convert dates to cell array of strings if necessary
    if ischar(dates)
        dates = cellstr(dates);
    elseif isdatetime(dates)
        dates = cellstr(datestr(dates, 'dd-mmm-yyyy HH:MM:ss'));
    elseif iscell(dates)
        dates = cellfun(@char, dates, 'UniformOutput', false);
    else
        error('Unexpected date format in file: %s', matFiles(k).name);
    end
    
    % Append the data to the aggregated vectors
    allBrightnessValues = [allBrightnessValues; brightnessValues];
    allDates = [allDates; dates];
end
% Convert the date strings to datetime format
allDates = datetime(allDates, 'InputFormat', 'dd-MMM-yyyy HH:mm:ss');
% Display the size of the aggregated vectors
disp(['Total number of brightness values: ', num2str(length(allBrightnessValues))]);
disp(['Total number of dates: ', num2str(length(allDates))]);
% Plotting
figure;
hold on;
% original plot
% for i = 1:numel(allDates)
%     % Plotting the stem for each date
%     stem(allDates(i), allBrightnessValues(i), 'filled');
%     % Extracting time information
%     time_info = datestr(allDates(i), 'HH:MM:SS');
%     % Adding time information on top of each stem
%     text(allDates(i), allBrightnessValues(i), time_info, 'VerticalAlignment', 'bottom', 'HorizontalAlignment', 'center');
% end
% modified plot
nnn = 1+[0 cumsum(number_of_data_thismonth)]; % cumulative sum of nb of data per month
for i = 1:numel(number_of_data_thismonth)
    ind_start = nnn(i);
    ind_stop = nnn(i+1) - 1;
    ll(i) =  ind_stop - ind_start +1; % ll is equal to number_of_data_thismonth, so we have a working code 
    % Plotting the stem for each date
    % x position is "center" data 
    ind = round(mean(ind_start:ind_stop));
    stem(repmat(allDates(ind),ll(i),1), allBrightnessValues(ind_start:ind_stop), 'filled');
    % Extracting time information
    time_info = datestr(allDates(ind_start:ind_stop), 'HH:MM:SS');
    % Adding time information on top of each stem
  text(repmat(allDates(ind),ll(i),1), allBrightnessValues(ind_start:ind_stop), time_info, 'VerticalAlignment', 'bottom', 'HorizontalAlignment', 'center');
end
hold off;
title('Brightness Temperature vs. Date');
xlabel('Date');
ylabel('Brightness Temperature');
datetick('x', 'yyyy-mm-dd', 'keeplimits');
ylim([180 280])
%% 
%Plotting
% figure;
% hold on;
% for i = 1:numel(allDates)
%     % Plotting the stem for each date
%     stem(allDates(i), allBrightnessValues(i), 'filled');
%     % Extracting time information
%     time_info = datestr(allDates(i), 'HH:MM:SS');
%     % Adding time information on top of each stem
%     text(allDates(i), allBrightnessValues(i), time_info, 'VerticalAlignment', 'bottom', 'HorizontalAlignment', 'center');
% end
% hold off;
% title('Brightness Temperature vs. Date');
% xlabel('Date'); axis normal;
% ylabel('Brightness Temperature');
% datetick('x', 'yyyy-mm-dd', 'keeplimits');

2 个评论
显示无隐藏无

Amjad Iqbal 2024-5-22

@Mathieu NOE

I really appreciate the time and efforts to provide the solution. I have modified the plot and I wanted to plot a neat one. Attached one is the finest result. I am thank full for all the experts to respond promptly.