I have created a heat map I want to give time series (1980-2019) monthly as x ticks I have daily rainfall data .

clc; clear all; close all;

addpath 'D:\data\Heat_map\New folder'

addpath 'D:\data\Heat_map\New folder\';

cor_path='D:\data\Heat_map\'

Kendall_Tau = xlsread(sprintf('%s%s%s',fullfile(cor_path),'Heat_map_matrix_rainfall.xlsx'));

Z_Dependence1 = Kendall_Tau(1:end,4:end);

figure(1);

t1 = datetime(1980,1,1);

t2 = datetime(2019,12,1);

Tall = t1:caldays(1):t2;

Tall = t1:caldays(1):t2;

Tall = Tall';

Z = datevec(Tall);

Z(:, ~any(Z,1) ) = []; %columns

y = heatmap(Z_Dependence1,[], [])

mycolormap=customcolormap([0 1],{'#FFFFFF', '#00FF00'});

colorbar;

colormap(mycolormap);

if ismatrix(Z_Dependence1)==1

set(y, 'AlphaData', ~isnan(Z_Dependence1))

end

set(gca, 'Color', [0.8, 0.8, 0.8]);

set(gca,'FontName','Arial','FontSize',11);

if ismatrix(Z_Dependence1)==1

set(y, 'AlphaData', (Z_Dependence1==1005))

end

set(gca, 'Color', [1, 1, 1]);

xticks(1980:5:2019)

set(gca,'Ytick',[1:1:11],'yticklabel',({'TEHRI','GANGTOK', 'KAKIMPONG','DARJEELING','GUWAHATI','KOHIMA','SHILLONG','SILCHAR','IMPHAL','AGARTALA','AIZWAL'}))

H_Slope = heatmap(U1_Qpeak,[],[],[],'GridLines', 'None','colorbar', false,'fontsize',12);

Xlabel = [1889:10:1980];

serialDates = datenum(num2str(Xlabel(:)), 'yyyy');

Xlabel_str = datestr(serialDates,10);

set(gca,'Xtick',[1:1200:13],'xticklabel',({'1970-1974','1980-1990','1985-1987','1985-1989','1985-1990','1996-2004','2001-2003','2001-2007'...

'2005-2008','2008-2010','2010-2015','2010-2019','2012-2019'}),'Fontname','Arial','Fontsize',20)

% rotateXLabels(gca(), 45);

set(gca,'fontname','arial','fontsize',12);

serialDates = datenum(num2str(Xlabel(:)), 'yyyy');

Xlabel_str = datestr(serialDates);

set(gca,'Xtick',[1:5:33],'xticklabel',{Xlabel_str});

rotateXLabels(gca(), 45);

grad=colorGradient([1 0 0],[0.5 0.8 1],128);

surf(peaks)

colormap(grad);

[grad,im]=colorGradient([1 0 0],[0.5 0.8 1],128);

image(im); %display an image with the color gradient.

• I want to insert xticks as timeseries from 1980-2019 monthly and also i want to define color for values such as zero and NaN(the color should be different for both values)

Answer 1

[Aditya]

Hi Danish,

From your query what I understood is that you wanted to insert xticks as timeseries in your heatmap and wanted to change the color of values such as zero and NaN.

To insert xticks as a timeseries in your heatmap, you can use the following code snippet:

% Set x-axis tick locations and labels
startYear = 1980;
endYear = 2019;
numYears = endYear - startYear + 1;
monthsPerYear = 12;
numMonths = numYears * monthsPerYear;

% Generate the date labels for the x-axis
dates = datetime(startYear, 1, 1) + calmonths(0:numMonths-1);
dateLabels = cellstr(datestr(dates, 'yyyy-mm'));

% Set the x-axis tick locations and labels
h.XDisplayData = 1:numMonths;
h.XDisplayLabels = dateLabels;

To change the color of zero and NaN values, you can use the following code snippet:

% Set the colormap
map = colormap(heatmap(data));
map(1,:) = [1 0 0]; % changes the color of values that are zero

% Create the heatmap with modified colormap
figure;
h = heatmap(data, 'Colormap', map, 'MissingDataColor',[0.8 0.8 0.8]); % ‘MissingDataColor’ helps to color the NaN values

Hope this helps!