change colors for each bins in histogram

Hi, I have attached sample data, I plot histogram for the sample data as: hist = histogram(sample)

I need to color each bin(group of values) in different, and put annotation text in figure what each color represent :

[Walter Roberson]

Which MATLAB version are you using? This task got more difficult as of R2014b.

[bero]

matlab R2015a

Answer 1

[Walter Roberson]

From R2014b onwards, the only way to do it is to bar() in each entry one at a time, specifying the color you want. Well, you could also use patch() or fill() or rectangle() to put in the bars; the point is that histogram objects do not allow you to change the bar colors individually now.

[bero]

Could you please do it for 2 entry with the annotation text??in any sample example... Thx

Answer 2

[Srivathsan Iyengar]

One way to do it is to overlay multiple histogram plots on the same axes, one plot for each bin. This makes sense for reasonable number of bins, not for large number of bins.

Here's an example code:

load sample.mat;

xValues = unique(sample);

binColors = [repmat(reshape(repmat(0:0.5:1,9,1),27,1),1,1) repmat(reshape(repmat(0:0.5:1,3,1),9,1),3,1) repmat(reshape(repmat(0:0.5:1,1,1),3,1),9,1)];

hf = figure; hax = axes; hold on;
legendStr = cell(1,length(xValues));
for i=1:length(xValues)
     histogram(hax, sample(sample == xValues(i)), 'FaceColor',binColors(i,:));    
     legendStr(i) = {num2str(xValues(i))};
end
legend(legendStr);

[Adam Danz]

Make sure to explicitly set the bin widths or bin edges so that the overlayed histrograms line up properly.

[Giuseppe Degan Di Dieco]

Hello Guys,

I'd be glad if you could help me in building a histogram with different color for each histogram bin.

Before asking, I've tried to define for loops and a matrix of colors, without succeding.

My problem is that T.ConstructionYear is a 1531 x 1 numeric vector, and I'd have a different color for each bin. I left auto mode for the number of bins choice.

I've also tried to write the function for just two bins.

h1 = histogram(T.ConstructionYear, 'FaceColor', 'b');
xlabel('ConstructionYear');
ylabel('Number of Bridges');
title('Distribution of Construction Year Data');

Thanks in advance for your help.

[Marion Baques]

Hi,

I found a solution for your problem:

Fit=colormap(jet(56)); % your colormap with the number of colors you want.

cpt=1; % your counter

for i=0:365:20075 % for me it was on the time

edges0=[i:365:i+365];

histogram(T.ConstructionYear,edges0,'FaceColor',Fit(cpt,:));

hold on

cpt=cpt+1;

end

Hope it will help!

[Charmi Patel]

Hello Marion,

Thank you for your solution. It was really helpful to me. But I get an error on the line colormap('jet',56) on R2021b version that first argument must be scalar axes or figure handle. Can you please confirm which version are you using? Also it would be great if you have some solution to this

Thanks!

[Marion Baques]

Hello Charmi,

I think the error comes from the way the colormap function is written. It is my mistake as I use the crameri colorscale (scientific colorscale). If you write "colormap(jet(56))", it works. I tried for me and it is working the same.

Hope this solves your problem!