www.gusucode.com > stats 源码程序 matlab案例代码 > stats/SummaryStatisticsGroupedbyCategoryExample.m
%% Summary Statistics Grouped by Category % This example shows how to compute summary statistics grouped by levels % of a categorical variable. You can compute group summary statistics for % a numeric array or a dataset array using |grpstats|. % Copyright 2015 The MathWorks, Inc. %% Load sample data. load hospital %% % The dataset array, |hospital|, has 7 variables (columns) and 100 observations % (rows). %% Compute summary statistics by category. % The variable |Sex| is a nominal array with two levels, |Male| and |Female|. % Compute the minimum and maximum weights for each gender. stats = grpstats(hospital,'Sex',{'min','max'},'DataVars','Weight') %% % The dataset array, |stats|, has observations corresponding to the levels % of the variable |Sex|. The variable |min_Weight| contains the minimum % weight for each group, and the variable |max_Weight| contains the maximum % weight for each group. %% Compute summary statistics by multiple categories. % The variable |Smoker| is a logical array with value |1| for smokers and % value |0| for nonsmokers. Compute the minimum and maximum weights for % each gender and smoking combination. stats = grpstats(hospital,{'Sex','Smoker'},{'min','max'},... 'DataVars','Weight') %% % The dataset array, |stats|, has an observation row for each combination % of levels of |Sex| and |Smoker| in the original data.