octave中自定义函数

 1 function [y1,y2,y3,y4]=f4(a,b)
 2     y1=a+b;
 3     y2=a-b;
 4     y3=a*b;
 5     if b==0
 6         printf('b is 0, dont divide!\n');
 7         y4=3.14
 8     else
 9         y4=a/b;
10     endif
11 end