第1个回答 2013-11-29
clear>clc>x=0:0.2:9 >plot(x ,sin(x),'_ r +',x,cos(x),': k *');>legend('first','second',4) >grid on >title ('this is an example sin cos \rightarrow 2\pi')>text (3.14,sin(3.14),\leftarrow zero for \pi') >text (3.14 ,cos(3.14),\leftarrow -1 for\pi')