How can I print the mean and standard deviation in the histogram plot?

Hi there

Dear all, I used the syntax below to plot the histogram:

h = histfit(x)

A probability distribution is also obtained from:

pd = fitdist(x,'Normal')

How can I automatically display the mean (mu) and standard deviation (sigma) in the histogram plot?

Answer 1

[Image Analyst]

I don't know if you can do it "automatically" but you can manually use title or text to display text on the chart:

x = randn(1000, 1);
h = histfit(x)

h = 
  2×1 graphics array:

  Bar
  Line

% A probability distribution is also obtained from:
pd = fitdist(x,'Normal')

pd = 
  NormalDistribution

  Normal distribution
       mu = 0.0281218   [-0.0336199, 0.0898636]
    sigma =  0.994957   [0.953181, 1.04059]

grid on;
% Display the mean and std dev.
caption = sprintf('Mean = %f, StDev = %f', pd.mu, pd.sigma);
title(caption)

[Navid]

I appreciate your assistance very much.

[Paul Barrette]

Note that 'fitdist' requires Matlab's Statistics_Toolbox

[Navid]

I'm eager to learn more about it! Would you mind sharing additional details with me? Your insights would be greatly appreciated!

[Paul Barrette]

I do not yet have that tool box (the quote I got for this license is about USD 1000), so am unable to comment on that function.

[Navid]

I am grateful you took the time to share this information with me. Your assistance is highly appreciated.

Answer 2

[Walter Roberson]

You can text the information into place. Or you can put it into a title or subtitle

Answer 3

[Steven Lord]

The other posters have interpreted "print" in the subject of your Answers post as displaying the numeric value. Another potential interpretation of that (and the word you used later in your question, "display") is to draw lines representing the mean and standard deviations. If you're interested in that visualization of the statistical quantities, use the xline function. I've slightly adapted the "Create Multiple Lines with Labels" example from that page for the example below.

x = randn(1, 1e5); % Sample data
h = histogram(x);
m = mean(x);
s = std(x);
xline([m, m-s, m+s], ":", ["\mu", "\mu- \sigma", "\mu+ \sigma"], ...
    "Color", "r", "FontWeight", "bold")

[Navid]

I appreciate your assistance. However, as you know, the xline syntax is only supported by newer versions. Thank you again for your help.