This example shows how to use the t location-scale probability distribution object to work with a Cauchy distribution with nonstandard parameter values.
Create a location-scale probability distribution object with degrees of freedom nu = 1
. Specify mu = 3
to set the location parameter equal to 3, and sigma = 1
to set the scale parameter equal to 1.
pd = makedist('tLocationScale','mu',3,'sigma',1,'nu',1)
pd = tLocationScaleDistribution t Location-Scale distribution mu = 3 sigma = 1 nu = 1
Use object functions to compute descriptive statistics for the Cauchy distribution.
med = median(pd)
med = 3
r = iqr(pd)
r = 2
m = mean(pd)
m = NaN
s = std(pd)
s = Inf
The median of the Cauchy distribution is equal to its location parameter, and the interquartile range is equal to two times its scale parameter. Its mean and standard deviation are undefined.
Compute and plot the pdf of the Cauchy distribution.
x = -20:1:20;
y = pdf(pd,x);
plot(x,y,'LineWidth',2)
The peak of the pdf is centered at the location parameter mu = 3
.
Generate a column vector containing 10 random numbers from the Cauchy distribution using the random
function for the location-scale probability distribution object.
rng('default'); % For reproducibility r = random(pd,10,1)
r = 10×1
3.2678
4.6547
2.0604
4.7322
3.1810
1.6649
1.8471
4.2466
5.4647
8.8874
Generate a 5-by-5 matrix of Cauchy random numbers.
r = random(pd,5,5)
r = 5×5
2.2867 2.9692 -1.7003 5.5949 1.9806
2.7421 2.7180 3.2210 2.4233 3.1394
3.5966 3.9806 1.0182 6.4180 5.1367
5.4791 15.6472 0.7558 2.8908 5.9031
1.6863 4.0985 2.9934 13.9506 4.8792