a =
Columns 1 through 23
2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83
Columns 24 through 25
89 97
>> na=length(a)%%得到質數的個數
na =
25
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
>> x=1:100;
>> b=0;c=0;%%
>> xx=mod(x,2);%%對x求余，即x除以2的余數
>> for i=1:100
if xx(i)==1
b=b+1;%%奇數個數累計
else
c=c+1;%%偶數個數累計
end
end
b
c
b =
50
c =
50