基本資料：
data = rand(25)+repmat(1:25,25,1);
H = plot(data);
基本用法：
legend({'str1','str2','strn'});
進階用法1：指定legend顯示的位置：
legend({'str1','str2','strn'},1);
legend({'str1','str2','strn'},2);
legend({'str1','str2','strn'},'Location','SouthEast');
可選的位置很多：
North：Inside plot box near top
South：Inside bottom
EastI：nside right
West：Inside left
NorthEast：Inside top right (default)
NorthWest：Inside top left
SouthEast：Inside bottom right
SouthWest：Inside bottom left
NorthOutside：Outside plot box near top
SouthOutside：Outside bottom
EastOutside：Outsideright
WestOutside：Outside left
NorthEastOutside：Outside top right
NorthWestOutside：Outside top left
SouthEastOutside：Outside bottom right
SouthWestOutside：Outside bottom left
Best：Least conflict with data in plot
BestOutside：Least unused space outside plot
通常，用'Best‘比較不錯
進階用法2：指定顯示某幾條曲線的legend：
方法1：複雜到吐血
例如你有25條曲線，想顯示其中1，6，11，16，21的legend，則
for i = [2:5 7:10 12:15 17:20 22:25]
set(get(get(H(i),'Annotation'),'LegendInformation'),'IconDisplayStyle','off'); end
legend('1','6','11','16','21');
方法2：簡單到郁悶
H = plot(data);
legend(H([1 6 11 16 21],'1,'6','11’,'16','21');
進階用法3：legend橫排
hl = legend(H([1 6 11 16 21],'1,'6','11’,'16','21');
set(hl,'Orientation','horizon')
進階用法4：不顯示方框：
hl = legend(H([1 6 11 16 21],'1,'6','11’,'16','21');
set(hl,'Box','off');
參考文獻