function?read_comtrade

%%?Comtrade?Reader?function
%?
%?This?file?is?designed?to?decode?the?data?stored?in?COMTRADE?format?
%?as?defined?in?IEEE?C37.111-1999.?This?involves?the?opening?of?two?files?
%?one?containing?the?configuration?（.cfg）?information?and?the?other?
%?the?data?（.dat）.
%?
%?COMTRADE?provides?a?common?format?for?the?data?files?and?exchange?medium?
%?needed?for?the?interchange?of?various?types?of?fault?test?or?simulation?
%?data.

%%?open?the?comtrade?files?&?extract?the?data

%?read_comtrade（filename）
%??Imports?data?from?the?specified?file
%??filename:??files?to?read?.cfg?and?.dat

%??Auto-generated?by?MATLAB?on?12-Jul-2007?13:45:45

%?Use?the?uigetfile?function?to?load?the?.cfg?file?which?is?then?used?to
%?load?the?associated?.dat?file

%?First?get?the?.cfg?file?information
[CfgFileNamePath]?=?uigetfile（‘*.cfg‘）;%載入.CFG文件
PathAndCfgName?=[Path?CfgFileName];?????%PathAndCfgName?=路徑\文件名.cfg??eg.?PathAndCfgName?=E:\研究生\項(xiàng)目\READE_comtrade\262-RCS902A.cfg

%?Derive?the?.dat?file?string
DatFileName?=?strcat（sscanf（CfgFileName‘%1s‘length（CfgFileName）-4）?‘.dat‘）;%DatFileName=262-RCS902A.dat
PathAndDatName?=[Path?DatFileName];???????????????????????????????????????????%DatFileName=E:\研究生\項(xiàng)目\READE_comtrade\262-RCS902A.dat

%?Store?the?file?name?（minus?extension）?and?path?in?the?workspace
assignin（‘base‘‘Path‘?Path）;
assignin（‘base‘‘FileName‘?sscanf（CfgFileName‘%1s‘length（CfgFileName）-4））;

%?Now?open?the?.cfg?and?.dat?files
cfg_id?=?fopen（PathAndCfgName）;
dat_id?=?fopen（PathAndDatName）;
%?Scan?the?text?into?local?cells?cfg?and?dat.
cfg?=?textscan（cfg_id?‘%s‘?‘delimiter‘?‘\n‘）;????%返回的?cfg?is?a?single?cell?array
dat?=?textscan（dat_id?‘%s‘?‘delimiter‘?‘\n‘）;????%fopen和textscan配對(duì)使用

%?close?all?open?files?as?we‘re?done?with?them?now.
fclose（‘a(chǎn)ll‘）;

%%?start?to?decode?the?data

cfg_len?=?length（cfg{11}）;
cfg_string?=?cell（size（cfg））;%made?a?empty?cell?array?whose?size?equalls?to?the?cfg?

for?i?=?1:cfg_len
????temp_string?=?char（cfg{11}{i}）;
????cfg_string（i）?=?textscan（temp_string?‘%s‘?‘Delimiter‘?‘‘）‘;
end

%?Comtrade?File?Identifier
title?=?char（cfg_string{11}（1））;

%?Comtrade?Version
if?length（cfg_string{11}）?
????Version?=?‘1999‘;
else
????Version?=?char（cfg_string{11}（3））;
end

%?Channel?information:?total?analogues?and?digitals
No_Ch?=?strread（char（cfg_string{12}（1）））;%No_Ch?is?a?1-by-N?vector
Ana_Ch?=?strread（char（cfg_string{12}（2）））;
Dig_Ch?=?strread（char（cfg_string{12}（3）））;

%?Data?length?i.e.?no?of?samples
dat_len?=?strread（char（cfg_string{15+No_Ch}（2）））;?

%?Nominal?frequency?
frequency?=?strread（char（cfg_string{13+No_Ch}（1）））;

%?Sampling?rate
samp_rate?=?strread（char（cfg_string{15+No_Ch}（1）））;

%?Record?started
start_date?=?char（cfg_string{16+No_Ch}（1））;
start_time?=?char（cfg_string{16+No_Ch}（2））;

%?Record?ended
end_date?=?char（cfg_string{17+No_Ch}（1））;
end_time?=?c