In data analysis, it is difficult to judge whether the median is valid or whether there are outliers without knowing the data distribution.
Outliers are points that deviate from the regularity of most points.
In order to divide the overall data more effectively, the concept of quartiles is proposed. That is, the lower bound of the concept, the 0.25 locus, the 0.75 locus, and the upper bound of the concept are selected.
There is a graph that specifically represents quartile points called a boxplot. (As the name suggests, those that meet the conditions are inside the box, and those that are not satisfied are outside the box). There is also a function boxplot for making boxplots in matlab. Let's talk about its syntax.
First draw the simplest boxplot:
boxplot(A);%A是一个列向量
The renderings are as follows:
