How to plot a heat map with three vectors?

I have 3 vectors of hour of day , day of a year and temperature data . The temperature data measured 4 times a day. and for 365 days. I would like to plot a heat map like this

Answer 1

[Akbar]

I have made some modifications. The heatmap below Shows highest temp. each hour of a month, for two years.

% creating table (i hope you are using new Version of matlab 
% which has table function, otherwise try dataset)
t1 = datetime(2016,01,1,8,0,0);
t2 = datetime(2018,01,1,8,0,0);
t = t1:hours(1):t2;
myTable = table(t',year(t'),month(t'),day(t'),hour(t'));
myTable.Properties.VariableNames = {'date' 'year' 'month' 'day' 'hour'};
a = 0;
b = 40;
r = (b-a).*rand(17545,1) + a;
myTable.temp = r;

% Create categorical arrays from the month 
% and hour columns of the table. 
% Then determine the unique months and hours 
% to use as labels along the x-axis and y-axis.
months = categorical(myTable.month);
hours = categorical(myTable.hour);
xlabels = categories(months);
ylabels = categories(hours);
%Determine the final size of the resulting 
%color data based on the number of unique months and hours. 
nummonths = numel(xlabels);
numhours = numel(ylabels);

%Convert the categorical months and hours arrays 
%into numeric indices to use with the accumarray function. 
%Compute the color data as the maximum temperature for each 
%month and hour combination using the accumarray function. 
%Use NaN for missing month and year combinations.
x = double(months);
y = double(hours);
temps = myTable.temp;
cdata = accumarray([y,x],temps,[numhours,nummonths],@max,NaN);
%Create the heatmap. Label the x-axis and y-axis with the 
%months and years, respectively. Color the heatmap cells 
%using the computed matrix data.

h = heatmap(xlabels,ylabels,cdata);

[Rita]

Thanks a lot

Answer 2

[Ameer Hamza]

You can make such a graph using pcolor(). The actual procedure depends on the format your data is available. You might need to use findgroups() and splitapply first to separate your data and then use pcolor() to plot the graph.

[Rita]

Thanks Ameer.I don't think pcolor can plot what I wanted. I would like to use "heatmap" and I also would like to show nans as well.