clc
clear
?%導入pages.txt文件，獲取文章中的字符串
fid?=?fopen（‘a.txt‘）;???????????????
tline?=?fgetl（fid）;
%變量初始化
i?=?1;
test?=?[];
j?=?1;
str1?=?‘‘;

while?ischar（tline）
????disp（tline）;????????????????????%顯示每一行
????pages{i}?=?tline;???????????????%將文章中的每一行的字符串存在數據類型為元包（cell）變量中
????tline?=?fgetl（fid）;
????i=i+1;
end
fclose（fid）;

%for循環?實現pages中的所有行字符串存儲在同一個名為：str的字符串變量中
for?i=1:length（pages）
????str?=?strcat（str1pages{i}）;
????str1?=?str;
end
str;???????????????????????????????%拿str字符串，自行與文章全文進行校對
a?=?lower（str）;????????????????????%大寫字母轉小寫
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%
%濾除其他字符，只計算英文字符
for?i=1:length（a）
????if（a（i）>=‘a‘）
????????if（a（i）<=‘z‘）
????????test（j）?=?a（i）;
????????j?=?j?+?1;
????????end
????end
end
st=sprintf（‘%c‘test）??????????????%顯示最終要統計的英文字符
%%
char?=?unique（st）;?????????????????%計算有多少個不重復的字符串

for?i?=?1:length（char）
????char（i）;
????number（i）?=?length（strfind（stchar（i）））;?%統計字符的數目
end
char???????????????????????????????%顯示字符
number?????????????????????????????%顯示個數

%計算頻率frequency
frequency?=?number/sum（number）?????%這里進行一個計算只為了與上面的number現實的個數相對應（這個frequency與下面那個frequency只是順序不同）
%分別將所有出現過的字符：char每個char出現的次數：number每個char出現的頻率：frequency
number?=?sort（number2‘descend‘）?;?%做一個降序，方便下面進行編碼
frequency?=?number/sum（number）;?????%再次計算頻率
%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%哈夫曼編碼%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%
%哈夫曼編碼主程序????
disp（‘%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%哈夫曼編碼%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%‘）
r=2;????????????????????????????????%r代表r元碼
Huffman_CLQ（frequencyr）
disp（‘%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%香農編碼%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%‘）
%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%香農編碼%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
shannon_result?=?shannon（frequency）

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件????????145??2018-01-11?14:55??上傳文件\a.txt

?????文件???????2265??2018-01-12?01:15??上傳文件\CalculateLetters_Number.m

?????文件????????276??2018-01-11?15:25??上傳文件\check.m

?????文件????????253??2018-01-11?15:27??上傳文件\first_S.m

?????文件???????2407??2018-01-11?15:58??上傳文件\Huffman_CLQ.m

?????文件???????1661??2018-01-12?01:16??上傳文件\shannon.m

?????文件????????919??2018-01-11?15:46??上傳文件\yasuo_pp.m

?????目錄??????????0??2018-01-11?15:58??上傳文件

-----------?---------??----------?-----??----

?????????????????7926????????????????????8