www.gusucode.com > stats 源码程序 matlab案例代码 > stats/CreateOrdinalArraysExample.m
%% Create Ordinal Arrays % This example shows how to create ordinal arrays using |ordinal|. %% Load sample data. AllSizes = {'medium','large','small','small','medium',... 'large','medium','small'}; %% % The created variable, |AllSizes|, is a cell array of character vectors % containing size measurements on eight objects. %% Create an ordinal array. % Create an ordinal array with category levels and labels corresponding % to the values in the cell array (the default levels and labels). sizeOrd = ordinal(AllSizes); getlevels(sizeOrd) %% Explore category labels. % By default, |ordinal| uses the original character vectors as category labels. The % default order of the categories is ascending alphabetical order. getlabels(sizeOrd) %% Add additional categories. % Suppose that you want to include additional levels for the ordinal array, % |xsmall| and |xlarge|, even though they do not occur in the original data. % To specify additional levels, use the third input argument to |ordinal|. sizeOrd2 = ordinal(AllSizes,{},... {'xsmall','small','medium','large','xlarge'}); getlevels(sizeOrd2) %% Explore category labels. % To see which levels are actually present in the data, use |unique|. unique(sizeOrd2) %% Specify the category order. % Convert |AllSizes| to an ordinal array with categories |small| < |medium| % < |large|. Generally, an ordinal array is distinct from a nominal array % because there is a natural ordering for levels of an ordinal array. You % can use the third input argument to |ordinal| to specify the ascending % order of the levels. Here, the order of the levels is smallest to largest. sizeOrd = ordinal(AllSizes,{},{'small','medium','large'}); getlevels(sizeOrd) %% % The second input argument for |ordinal| is a list of labels for the category % levels. When you use braces |{}| for the level labels, |ordinal| uses % the labels specified in the third input argument (the labels come from % the levels present in the data if only one input argument is used). %% Compare elements. % Verify that the first object (with size |medium|) is smaller than the % second object (with size |large|). sizeOrd(1) < sizeOrd(2) %% % The logical value |1| indicates that the inequality holds.